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Sample records for access control protocol

  1. Efficient medium access control protocol for geostationary satellite systems

    Institute of Scientific and Technical Information of China (English)

    王丽娜; 顾学迈

    2004-01-01

    This paper proposes an efficient medium access control (MAC) protocol based on multifrequency-time division multiple access (MF-TDMA) for geostationary satellite systems deploying multiple spot-beams and onboard processing,which uses a method of random reservation access with movable boundaries to dynamically request the transmission slots and can transmit different types of traffic. The simulation results have shown that our designed MAC protocol can achieve a high bandwidth utilization, while providing the required quality of service (QoS) for each class of service.

  2. Distributed reservation control protocols for random access broadcasting channels

    Science.gov (United States)

    Greene, E. P.; Ephremides, A.

    1981-05-01

    Attention is given to a communication network consisting of an arbitrary number of nodes which can communicate with each other via a time-division multiple access (TDMA) broadcast channel. The reported investigation is concerned with the development of efficient distributed multiple access protocols for traffic consisting primarily of single packet messages in a datagram mode of operation. The motivation for the design of the protocols came from the consideration of efficient multiple access utilization of moderate to high bandwidth (4-40 Mbit/s capacity) communication satellite channels used for the transmission of short (1000-10,000 bits) fixed length packets. Under these circumstances, the ratio of roundtrip propagation time to packet transmission time is between 100 to 10,000. It is shown how a TDMA channel can be adaptively shared by datagram traffic and constant bandwidth users such as in digital voice applications. The distributed reservation control protocols described are a hybrid between contention and reservation protocols.

  3. Analyzing the effect of routing protocols on media access control protocols in radio networks

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, C. L. (Christopher L.); Drozda, M. (Martin); Marathe, A. (Achla); Marathe, M. V. (Madhav V.)

    2002-01-01

    We study the effect of routing protocols on the performance of media access control (MAC) protocols in wireless radio networks. Three well known MAC protocols: 802.11, CSMA, and MACA are considered. Similarly three recently proposed routing protocols: AODV, DSR and LAR scheme 1 are considered. The experimental analysis was carried out using GloMoSim: a tool for simulating wireless networks. The main focus of our experiments was to study how the routing protocols affect the performance of the MAC protocols when the underlying network and traffic parameters are varied. The performance of the protocols was measured w.r.t. five important parameters: (i) number of received packets, (ii) average latency of each packet, (iii) throughput (iv) long term fairness and (v) number of control packets at the MAC layer level. Our results show that combinations of routing and MAC protocols yield varying performance under varying network topology and traffic situations. The result has an important implication; no combination of routing protocol and MAC protocol is the best over all situations. Also, the performance analysis of protocols at a given level in the protocol stack needs to be studied not locally in isolation but as a part of the complete protocol stack. A novel aspect of our work is the use of statistical technique, ANOVA (Analysis of Variance) to characterize the effect of routing protocols on MAC protocols. This technique is of independent interest and can be utilized in several other simulation and empirical studies.

  4. A TDMA based media access control protocol for wireless ad hoc networks

    Science.gov (United States)

    Yang, Qi; Tang, Biyu

    2013-03-01

    This paper presents a novel Time Division Multiplex Access (TDMA) based Media Access Control (MAC) protocol of wireless Ad Hoc network. To achieve collision free transmission, time slots in a MAC frame are cataloged into three types, that is access slot, control slot and traffic slot. Nodes in the network access to the network in the access slot, and an exclusive control is allocated subsequently. Data packets are transmission by dynamic schedule the traffic slots. Throughput and transmission delay are also analyzed by simulation experiment. The proposed protocol is capable of providing collision free transmission and achieves high throughput.

  5. Directional Medium Access Control (MAC Protocols in Wireless Ad Hoc and Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    David Tung Chong Wong

    2015-06-01

    Full Text Available This survey paper presents the state-of-the-art directional medium access control (MAC protocols in wireless ad hoc and sensor networks (WAHSNs. The key benefits of directional antennas over omni-directional antennas are longer communication range, less multipath interference, more spatial reuse, more secure communications, higher throughput and reduced latency. However, directional antennas lead to single-/multi-channel directional hidden/exposed terminals, deafness and neighborhood, head-of-line blocking, and MAC-layer capture which need to be overcome. Addressing these problems and benefits for directional antennas to MAC protocols leads to many classes of directional MAC protocols in WAHSNs. These classes of directional MAC protocols presented in this survey paper include single-channel, multi-channel, cooperative and cognitive directional MACs. Single-channel directional MAC protocols can be classified as contention-based or non-contention-based or hybrid-based, while multi-channel directional MAC protocols commonly use a common control channel for control packets/tones and one or more data channels for directional data transmissions. Cooperative directional MAC protocols improve throughput in WAHSNs via directional multi-rate/single-relay/multiple-relay/two frequency channels/polarization, while cognitive directional MAC protocols leverage on conventional directional MAC protocols with new twists to address dynamic spectrum access. All of these directional MAC protocols are the pillars for the design of future directional MAC protocols in WAHSNs.

  6. Design and Analysis of an Attack Resilient and Adaptive Medium access Control Protocol for Computer Networks

    CERN Document Server

    Shukla, Piyush Kumar; Bhadoria, Dr Sarita Singh

    2009-01-01

    The challenge of designing an efficient Medium Access Control (MAC) protocol and analyzing it has been an important research topic for over 30 years. This paper focuses on the performance analysis (through simulation) and modification of a well known MAC protocol CSMA/CD. The existing protocol does not consider the wastage of bandwidth due to unutilized periods of the channel. By considering this fact, performance of MAC protocol can be enhanced. The purpose of this work is to modify the existing protocol by enabling it to adapt according to state of the network. The modified protocol takes appropriate action whenever unutilized periods detected. In this way, to increase the effective bandwidth utilization and determine how it behaves under increasing load, and varying packet sizes. It will also include effects of attacks i.e. Denial of service attacks, Replay Attack, Continuous Channel Access or Exhaustion attack, Flooding attack, Jamming (Radio interference) attack, Selective forwarding attack which degrade...

  7. A distributed Synchronous reservation multiple access control protocol for mobile Ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yanling; SUN Xianpu; LI Jiandong

    2007-01-01

    This study proposes a new multiple access control protocol named distributed synchronous reservation multiple access control protocol.in which the hidden and exposed terminal problems are solved,and the quality of service(QoS)requirements for real-time traffic are guaranteed.The protocol is founded on time division multiplex address and a different type of traffic is assigned to difierent priority,according to which a node should compete for and reserve the free slots in a different method.Moreover,there is a reservation acknowledgement process before data transmit in each reserved slot,so that the intruded terminal problem is solved.The throughput and average packets drop probability of this protocol are analyzed and simulated in a fully connected network.the results of which indicate that this protocol is efficient enough to support the real-time traffic.and it is more suitable to MANETs.

  8. Energy-Efficient Reservation-Based Medium Access Control Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kohvakka Mikko

    2010-01-01

    Full Text Available In Wireless Sensor Networks (WSNs, a robust and energy-efficient Medium Access Control (MAC protocol is required for high energy efficiency in harsh operating conditions, where node and link failures are common. This paper presents the design of a novel MAC protocol for low-power WSNs. The developed MAC protocol minimizes the energy overhead of idle time and collisions by strict frame synchronization and slot reservation. It combines a dynamic bandwidth adjustment mechanism, multi-cluster-tree network topology, and a network channel allowing rapid and low-energy neighbor discoveries. The protocol achieves high scalability by employing frequency and time division between clusters. Performance analysis shows that the MAC protocol outperforms current state-of-the-art protocols in energy efficiency, and the energy overhead compared to an ideal MAC protocol is only 2.85% to 27.1%. The high energy efficiency is achieved in both leaf and router nodes. The models and the feasibility of the protocol were verified by simulations and with a full-scale prototype implementation.

  9. An Efficient Medium Access Control Protocol with Parallel Transmission for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mitsuji Matsumoto

    2012-08-01

    Full Text Available In this paper, we present a novel low power medium access control protocol for wireless sensor networks (WSNs. The proposed protocol, EP-MAC (Efficient MAC with Parallel Transmission achieves high energy efficiency and high packet delivery ratio under different traffic load. EP-MAC protocol is basically based on the Time Division Multiple Access (TDMA approach. The power of Carrier Sense Multiple Access (CSMA is used in order to offset the fundamental problems that the stand-alone TDMA method suffers from, i.e., problems such as lack of scalability, adaptability to varying situations, etc. The novel idea behind the EP-MAC is that it uses the parallel transmission concept with the TDMA link scheduling. EP-MAC uses the methods for the transmission power adjustment, i.e., uses the minimum level power necessary to reach the intended neighbor within a specified bit error rate [BER] target. This reduces energy consumption, as well as further enhances the scope of parallel transmission of the protocol. The simulation studies support the theoretical results, and validate the efficiency of our proposed EP-MAC protocol.

  10. Experimental Investigation on Transmission Control Protocol Throughput Behavior in Optical Fiber Access Networks

    Science.gov (United States)

    Tego, Edion; Matera, Francesco; del Buono, Donato

    2016-03-01

    This article describes an experimental investigation on the behavior of transmission control protocol in throughput measurements to be used in the verification of the service-level agreement between the Internet service provider and user in terms of line capacity for ultra-broadband access networks typical of fiber-to-the-x architectures. It is experimentally shown different conditions in high bandwidth-delay product links where the estimation of the line capacity based on a single transmission control protocol session results are unreliable. Simple equations reported in this work, and experimentally verified, point out the conditions in terms of packet loss, time delay, and line capacity, that allow consideration of the reliability of the measurement carried out with a single transmission control protocol session test by adopting a suitable measurement time duration.

  11. An extended smart utilization medium access control (ESU-MAC) protocol for ad hoc wireless systems

    Science.gov (United States)

    Vashishtha, Jyoti; Sinha, Aakash

    2006-05-01

    The demand for spontaneous setup of a wireless communication system has increased in recent years for areas like battlefield, disaster relief operations etc., where a pre-deployment of network infrastructure is difficult or unavailable. A mobile ad-hoc network (MANET) is a promising solution, but poses a lot of challenges for all the design layers, specifically medium access control (MAC) layer. Recent existing works have used the concepts of multi-channel and power control in designing MAC layer protocols. SU-MAC developed by the same authors, efficiently uses the 'available' data and control bandwidth to send control information and results in increased throughput via decreasing contention on the control channel. However, SU-MAC protocol was limited for static ad-hoc network and also faced the busy-receiver node problem. We present the Extended SU-MAC (ESU-MAC) protocol which works mobile nodes. Also, we significantly improve the scheme of control information exchange in ESU-MAC to overcome the busy-receiver node problem and thus, further avoid the blockage of control channel for longer periods of time. A power control scheme is used as before to reduce interference and to effectively re-use the available bandwidth. Simulation results show that ESU-MAC protocol is promising for mobile, ad-hoc network in terms of reduced contention at the control channel and improved throughput because of channel re-use. Results show a considerable increase in throughput compared to SU-MAC which could be attributed to increased accessibility of control channel and improved utilization of data channels due to superior control information exchange scheme.

  12. A survey of medium access control protocols for wireless ad hoc networks

    Directory of Open Access Journals (Sweden)

    Elvio João Leonardo

    2004-01-01

    Full Text Available A number of issues distinguishes Medium Access Control (MAC protocols for wireless networks from those used in wireline systems. In addition, for ad-hoc networks, the characteristics of the radio channel, the diverse physical-layer technologies available and the range of services envisioned make it a difficult task to design an algorithm to discipline the access to the shared medium that results efficient, fair, power consumption sensitive and delay bound. This article presents the current “state-of-art” in this area, including solutions already commercially available as well as those still in study.

  13. A concurrent access MAC protocol for cognitive radio ad hoc networks without common control channel

    Science.gov (United States)

    Timalsina, Sunil K.; Moh, Sangman; Chung, Ilyong; Kang, Moonsoo

    2013-12-01

    Cognitive radio ad hoc networks (CRAHNs) consist of autonomous nodes that operate in ad hoc mode and aim at efficient utilization of spectrum resources. Usually, the cognitive nodes in a CRAHN exploit a number of available channels, but these channels are not necessarily common to all nodes. Such a network environment poses the problem of establishing a common control channel (CCC) as there might be no channel common to all the network members at all. In designing protocols, therefore, it is highly desirable to consider the network environment with no CCC. In this article, we propose a MAC protocol called concurrent access MAC (CA-MAC) that operates in the network environment with no CCC. The two devices in a communication pair can communicate with each other even if they have only one common channel available. Therefore, the problems with CCC (such as channel saturation and denial of service attacks) can also be resolved. In CA-MAC, channel accesses are distributed over communication pairs, resulting in increased network connectivity. In addition, CA-MAC allows different communication pairs to access multiple channels concurrently. According to our performance study, CA-MAC provides higher network connectivity with shorter channel access delay compared to SYN-MAC, which is the conventional key MAC protocol for the network environment with no CCC, resulting in better network throughput.

  14. In-home Power Line Communication Media Access Control Protocol Based on Collision Resolution

    Institute of Scientific and Technical Information of China (English)

    WANG Bo; HUANG Pei-wei; ZHONG You-ping; QI Ying-hao

    2009-01-01

    Most existing media access control (MAC) protocols in power line communication (PLC) networks just discard the colliding data packets when collision occurs. The collision deteriorates throughput and delay performance of system under high traffic conditions. This article presents a novel media access scheme with fast collision resolution for in-home power line networks. It works by first recognizing the colliding stations through detecting the inserted unique ID sequence ahead of data packets, then the source nodes retransmitting their packets immediately after the collision slot. The proposed protocol maintains the benefits of ALOHA systems. It needs no scheduling overhead and is suitable for bursty sources, such as multimedia data packets. Computer simulations have demonstrated that this approach can achieve high throughput due to its ability of resolving collisions.

  15. Energy-Efficient Boarder Node Medium Access Control Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Abdul Razaque

    2014-03-01

    Full Text Available This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC for wireless sensor networks (WSNs, which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN, which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS, which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS, which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

  16. Energy-efficient boarder node medium access control protocol for wireless sensor networks.

    Science.gov (United States)

    Razaque, Abdul; Elleithy, Khaled M

    2014-03-12

    This paper introduces the design, implementation, and performance analysis of the scalable and mobility-aware hybrid protocol named boarder node medium access control (BN-MAC) for wireless sensor networks (WSNs), which leverages the characteristics of scheduled and contention-based MAC protocols. Like contention-based MAC protocols, BN-MAC achieves high channel utilization, network adaptability under heavy traffic and mobility, and low latency and overhead. Like schedule-based MAC protocols, BN-MAC reduces idle listening time, emissions, and collision handling at low cost at one-hop neighbor nodes and achieves high channel utilization under heavy network loads. BN-MAC is particularly designed for region-wise WSNs. Each region is controlled by a boarder node (BN), which is of paramount importance. The BN coordinates with the remaining nodes within and beyond the region. Unlike other hybrid MAC protocols, BN-MAC incorporates three promising models that further reduce the energy consumption, idle listening time, overhearing, and congestion to improve the throughput and reduce the latency. One of the models used with BN-MAC is automatic active and sleep (AAS), which reduces the ideal listening time. When nodes finish their monitoring process, AAS lets them automatically go into the sleep state to avoid the idle listening state. Another model used in BN-MAC is the intelligent decision-making (IDM) model, which helps the nodes sense the nature of the environment. Based on the nature of the environment, the nodes decide whether to use the active or passive mode. This decision power of the nodes further reduces energy consumption because the nodes turn off the radio of the transceiver in the passive mode. The third model is the least-distance smart neighboring search (LDSNS), which determines the shortest efficient path to the one-hop neighbor and also provides cross-layering support to handle the mobility of the nodes. The BN-MAC also incorporates a semi

  17. Spectrum sharing in cognitive radio networks medium access control protocol based approach

    CERN Document Server

    Pandit, Shweta

    2017-01-01

    This book discusses the use of the spectrum sharing techniques in cognitive radio technology, in order to address the problem of spectrum scarcity for future wireless communications. The authors describe a cognitive radio medium access control (MAC) protocol, with which throughput maximization has been achieved. The discussion also includes use of this MAC protocol for imperfect sensing scenarios and its effect on the performance of cognitive radio systems. The authors also discuss how energy efficiency has been maximized in this system, by applying a simple algorithm for optimizing the transmit power of the cognitive user. The study about the channel fading in the cognitive user and licensed user and power adaption policy in this scenario under peak transmit power and interference power constraint is also present in this book.

  18. A low power medium access control protocol for wireless medical sensor networks.

    Science.gov (United States)

    Lamprinos, I; Prentza, A; Sakka, E; Koutsouris, D

    2004-01-01

    The concept of a wireless integrated network of sensors, already applied in several sectors of our everyday life, such as security, transportation and environment monitoring, can as well provide an advanced monitor and control resource for healthcare services. By networking medical sensors wirelessly, attaching them in patient's body, we create the appropriate infrastructure for continuous and real-time monitoring of patient without discomforting him. This infrastructure can improve healthcare by providing the means for flexible acquisition of vital signs, while at the same time it provides more convenience to the patient. Given the type of wireless network, traditional medium access control (MAC) protocols cannot take advantage of the application specific requirements and information characteristics occurring in medical sensor networks, such as the demand for low power consumption and the rather limited and asymmetric data traffic. In this paper, we present the architecture of a low power MAC protocol, designated to support wireless networks of medical sensors. This protocol aims to improve energy efficiency by exploiting the inherent application features and requirements. It is oriented towards the avoidance of main energy wastage sources, such as idle listening, collision and power outspending.

  19. Medium Access Control Protocols for Wireless Sensor Networks with Energy Harvesting

    CERN Document Server

    Iannello, Fabio; Spagnolini, Umberto

    2011-01-01

    The design of Medium Access Control (MAC) protocols for wireless sensor networks (WSNs) has been conventionally tackled by assuming battery-powered devices and by adopting the network lifetime as the main performance criterion. While WSNs operated by energy-harvesting (EH) devices are not limited by network lifetime, they pose new design challenges due to the uncertain amount of harvestable energy. Novel design criteria are thus required to capture the trade-offs between the potentially infinite network lifetime and the uncertain energy availability. This paper addresses the analysis and design of WSNs with EH devices by focusing on conventional MAC protocols, namely TDMA, Framed-ALOHA (FA) and Dynamic-FA (DFA), and by accounting for the performance trade-offs and design issues arising due to EH. A novel metric, referred to as delivery probability, is introduced to measure the capability of a MAC protocol to deliver the measure of any sensor in the network to the intended destination (or fusion center, FC). T...

  20. Design of IP Camera Access Control Protocol by Utilizing Hierarchical Group Key

    Directory of Open Access Journals (Sweden)

    Jungho Kang

    2015-08-01

    Full Text Available Unlike CCTV, security video surveillance devices, which we have generally known about, IP cameras which are connected to a network either with or without wire, provide monitoring services through a built-in web-server. Due to the fact that IP cameras can use a network such as the Internet, multiple IP cameras can be installed at a long distance and each IP camera can utilize the function of a web server individually. Even though IP cameras have this kind of advantage, it has difficulties in access control management and weakness in user certification, too. Particularly, because the market of IP cameras did not begin to be realized a long while ago, systems which are systematized from the perspective of security have not been built up yet. Additionally, it contains severe weaknesses in terms of access authority to the IP camera web server, certification of users, and certification of IP cameras which are newly installed within a network, etc. This research grouped IP cameras hierarchically to manage them systematically, and provided access control and data confidentiality between groups by utilizing group keys. In addition, IP cameras and users are certified by using PKI-based certification, and weak points of security such as confidentiality and integrity, etc., are improved by encrypting passwords. Thus, this research presents specific protocols of the entire process and proved through experiments that this method can be actually applied.

  1. TraPy-MAC: Traffic Priority Aware Medium Access Control Protocol for Wireless Body Area Network.

    Science.gov (United States)

    Ullah, Fasee; Abdullah, Abdul Hanan; Kaiwartya, Omprakash; Cao, Yue

    2017-06-01

    Recently, Wireless Body Area Network (WBAN) has witnessed significant attentions in research and product development due to the growing number of sensor-based applications in healthcare domain. Design of efficient and effective Medium Access Control (MAC) protocol is one of the fundamental research themes in WBAN. Static on-demand slot allocation to patient data is the main approach adopted in the design of MAC protocol in literature, without considering the type of patient data specifically the level of severity on patient data. This leads to the degradation of the performance of MAC protocols considering effectiveness and traffic adjustability in realistic medical environments. In this context, this paper proposes a Traffic Priority-Aware MAC (TraPy-MAC) protocol for WBAN. It classifies patient data into emergency and non-emergency categories based on the severity of patient data. The threshold value aided classification considers a number of parameters including type of sensor, body placement location, and data transmission time for allocating dedicated slots patient data. Emergency data are not required to carry out contention and slots are allocated by giving the due importance to threshold value of vital sign data. The contention for slots is made efficient in case of non-emergency data considering threshold value in slot allocation. Moreover, the slot allocation to emergency and non-emergency data are performed parallel resulting in performance gain in channel assignment. Two algorithms namely, Detection of Severity on Vital Sign data (DSVS), and ETS Slots allocation based on the Severity on Vital Sign (ETS-SVS) are developed for calculating threshold value and resolving the conflicts of channel assignment, respectively. Simulations are performed in ns2 and results are compared with the state-of-the-art MAC techniques. Analysis of results attests the benefit of TraPy-MAC in comparison with the state-of-the-art MAC in channel assignment in realistic medical

  2. A Brief Survey of Media Access Control, Data Link Layer, and Protocol Technologies for Lunar Surface Communications

    Science.gov (United States)

    Wallett, Thomas M.

    2009-01-01

    This paper surveys and describes some of the existing media access control and data link layer technologies for possible application in lunar surface communications and the advanced wideband Direct Sequence Code Division Multiple Access (DSCDMA) conceptual systems utilizing phased-array technology that will evolve in the next decade. Time Domain Multiple Access (TDMA) and Code Division Multiple Access (CDMA) are standard Media Access Control (MAC) techniques that can be incorporated into lunar surface communications architectures. Another novel hybrid technique that is recently being developed for use with smart antenna technology combines the advantages of CDMA with those of TDMA. The relatively new and sundry wireless LAN data link layer protocols that are continually under development offer distinct advantages for lunar surface applications over the legacy protocols which are not wireless. Also several communication transport and routing protocols can be chosen with characteristics commensurate with smart antenna systems to provide spacecraft communications for links exhibiting high capacity on the surface of the Moon. The proper choices depend on the specific communication requirements.

  3. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

    Science.gov (United States)

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-09-18

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

  4. Sleeping Cluster based Medium Access Control Layer Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    T. R. Rangaswamy

    2012-01-01

    Full Text Available Wireless sensor networks play a vital role in remote area applications, where human intervention is not possible. In a Wireless Sensor Network (WSN each and every node is strictly an energy as well as bandwidth constrained one. Problem statement: In a standard WSN, most of the routing techniques, move data from multiple sources to a single fixed base station. Because of the greater number of computational tasks, the existing routing protocol did not address the energy efficient problem properly. In order to overcome the problem of energy consumption due to more number of computational tasks, a new method is developed. Approach: The proposed algorithm divides the sensing field into three active clusters and one sleeping cluster. The cluster head selection is based on the distance between the base station and the normal nodes. The Time Division Multiple Access (TDMA mechanism is used to make the cluster remain in the active state as well as the sleeping state. In an active cluster 50% of nodes will be made active and the remaining 50% be in sleep state. A sleeping cluster will be made active after a period of time and periodically changes its functionality. Results: Due to this periodic change of state, energy consumption is minimized. The performance of the Low Energy Adaptive and Clustering Hierarchy (LEACH algorithm is also analyzed, using a network simulator NS2 based on the number of Cluster Heads (CH, Energy consumption, Lifetime and the number of nodes alive. Conclusion: The simulation studies were carried out using a network simulation tool NS2, for the proposed method and this is compared with the performance of the existing protocol. The superiority of the proposed method is highlighted.

  5. Improvement in Medium Access Control protocol based on new contention scheme for wireless ad hoc network

    Directory of Open Access Journals (Sweden)

    C.Ellammal

    2012-05-01

    Full Text Available In todays wireless networks, stations using the IEEE 802.11 standard contend for the channel using the Distributed Coordination Function (DCF. Research has shown that DCF€™s performance degrades especially with the large number of stations. This becomes more concerning due to the increasing proliferation of wireless devices. In this paper, we present a Medium Access Control (MAC scheme for wireless LANs and compare its performance to DCF . Our scheme, which attempts to resolve the contention in a constant number of slots (or constant time, is called CONSTI. The contention resolution happens over a predefined number of slots. In a slot, the stations probabilistically send a jam signal on the channel. The stations listening retire if they hear a jam signal. The others continue to the next slot. Over several slots, we aim to have one station remaining in the contention, which will then transmit its data. We find the optimal parameters of CONSTI and present an analysis on its performance.

  6. Receiver-initiated medium access control protocols for wireless sensor networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Di Mauro, Alessio; Vithanage, Madava D.

    2015-01-01

    is to provide a comprehensive and self-contained introduction to the fundamentals of the receiver-initiated paradigm, providing newcomers with a quick-start guide on the state of the art of this field and a palette of options, essential for implementing applications or designing new protocols....

  7. Energy-Efficiency Analysis of a Distributed Queuing Medium Access Control Protocol for Biomedical Wireless Sensor Networks in Saturation Conditions

    Directory of Open Access Journals (Sweden)

    Christos Verikoukis

    2011-01-01

    Full Text Available The aging population and the high quality of life expectations in our society lead to the need of more efficient and affordable healthcare solutions. For this reason, this paper aims for the optimization of Medium Access Control (MAC protocols for biomedical wireless sensor networks or wireless Body Sensor Networks (BSNs. The hereby presented schemes always have in mind the efficient management of channel resources and the overall minimization of sensors’ energy consumption in order to prolong sensors’ battery life. The fact that the IEEE 802.15.4 MAC does not fully satisfy BSN requirements highlights the need for the design of new scalable MAC solutions, which guarantee low-power consumption to the maximum number of body sensors in high density areas (i.e., in saturation conditions. In order to emphasize IEEE 802.15.4 MAC limitations, this article presents a detailed overview of this de facto standard for Wireless Sensor Networks (WSNs, which serves as a link for the introduction and initial description of our here proposed Distributed Queuing (DQ MAC protocol for BSN scenarios. Within this framework, an extensive DQ MAC energy-consumption analysis in saturation conditions is presented to be able to evaluate its performance in relation to IEEE 802.5.4 MAC in highly dense BSNs. The obtained results show that the proposed scheme outperforms IEEE 802.15.4 MAC in average energy consumption per information bit, thus providing a better overall performance that scales appropriately to BSNs under high traffic conditions. These benefits are obtained by eliminating back-off periods and collisions in data packet transmissions, while minimizing the control overhead.

  8. Energy-efficiency analysis of a distributed queuing medium access control protocol for biomedical wireless sensor networks in saturation conditions.

    Science.gov (United States)

    Otal, Begonya; Alonso, Luis; Verikoukis, Christos

    2011-01-01

    The aging population and the high quality of life expectations in our society lead to the need of more efficient and affordable healthcare solutions. For this reason, this paper aims for the optimization of Medium Access Control (MAC) protocols for biomedical wireless sensor networks or wireless Body Sensor Networks (BSNs). The hereby presented schemes always have in mind the efficient management of channel resources and the overall minimization of sensors' energy consumption in order to prolong sensors' battery life. The fact that the IEEE 802.15.4 MAC does not fully satisfy BSN requirements highlights the need for the design of new scalable MAC solutions, which guarantee low-power consumption to the maximum number of body sensors in high density areas (i.e., in saturation conditions). In order to emphasize IEEE 802.15.4 MAC limitations, this article presents a detailed overview of this de facto standard for Wireless Sensor Networks (WSNs), which serves as a link for the introduction and initial description of our here proposed Distributed Queuing (DQ) MAC protocol for BSN scenarios. Within this framework, an extensive DQ MAC energy-consumption analysis in saturation conditions is presented to be able to evaluate its performance in relation to IEEE 802.5.4 MAC in highly dense BSNs. The obtained results show that the proposed scheme outperforms IEEE 802.15.4 MAC in average energy consumption per information bit, thus providing a better overall performance that scales appropriately to BSNs under high traffic conditions. These benefits are obtained by eliminating back-off periods and collisions in data packet transmissions, while minimizing the control overhead.

  9. An ultra low-power and traffic-adaptive medium access control protocol for wireless body area network.

    Science.gov (United States)

    Ullah, Sana; Kwak, Kyung Sup

    2012-06-01

    Wireless Body Area Network (WBAN) consists of low-power, miniaturized, and autonomous wireless sensor nodes that enable physicians to remotely monitor vital signs of patients and provide real-time feedback with medical diagnosis and consultations. It is the most reliable and cheaper way to take care of patients suffering from chronic diseases such as asthma, diabetes and cardiovascular diseases. Some of the most important attributes of WBAN is low-power consumption and delay. This can be achieved by introducing flexible duty cycling techniques on the energy constraint sensor nodes. Stated otherwise, low duty cycle nodes should not receive frequent synchronization and control packets if they have no data to send/receive. In this paper, we introduce a Traffic-adaptive MAC protocol (TaMAC) by taking into account the traffic information of the sensor nodes. The protocol dynamically adjusts the duty cycle of the sensor nodes according to their traffic-patterns, thus solving the idle listening and overhearing problems. The traffic-patterns of all sensor nodes are organized and maintained by the coordinator. The TaMAC protocol is supported by a wakeup radio that is used to accommodate emergency and on-demand events in a reliable manner. The wakeup radio uses a separate control channel along with the data channel and therefore it has considerably low power consumption requirements. Analytical expressions are derived to analyze and compare the performance of the TaMAC protocol with the well-known beacon-enabled IEEE 802.15.4 MAC, WiseMAC, and SMAC protocols. The analytical derivations are further validated by simulation results. It is shown that the TaMAC protocol outperforms all other protocols in terms of power consumption and delay.

  10. Adaptive digital access protocol: new features and performance improvements

    Science.gov (United States)

    Doshi, B. T.; Dravida, S.; Kustka, G. J.; Magill, Peter D.; Siller, Curtis A., Jr.; Kotikalapudi, Sriram

    1996-11-01

    This paper reports on a broadband multiple access protocol for bi-directional hybrid fiber-coax (HFC) networks. Referred to here as the enhanced adaptive digital access protocol (ADAPt+TM), it builds upon earlier work to define a medium access control (MAC) protocol amenable to a multiple service environment supporting subscriber access in HFC networks with tree and branch topologies. ADAPt+ efficiently supports different access modes such as synchronous transfer mode (STM), asynchronous transfer mode (ATM), and variable length (VL) native data (e.g., IP, IPX). This enhanced protocol adapts to changing demands for a mix of circuit- and packet-mode applications, and efficiently allocates upstream and downstream bandwidth to isochronous and bursty traffic sources. This paper describes: ADAPt+ for upstream communication and multiplexing/demultiplexing for downstream communication; its applicability to STM, ATM and other native data applications; and performance attributes such as bandwidth efficiency and latency.

  11. An Efficient Multi Access Protocol for Wireless Networks

    Directory of Open Access Journals (Sweden)

    T. Suryaprakash Reddy

    2010-09-01

    Full Text Available In this paper, we propose and evaluate an efficient multi-access protocol for cell-based wireless networks. Our protocol addresses the problems in existing random-access protocols for wireless networks: long-term fairness as well as short term fairness in accessing a shared channel and the detection of hidden and exposed collisions. Our proposed protocol is a limited contention protocol in which the set of contending mobiles are chosen based on a global common contention window maintained by every mobile station. The contention window is adjusted based on three possible channel states: no transmission, success, and collision. We assume that the channel state at the end of each contention slot is broadcast by a base station in a control channel. We show analytically that the time interval between two successive accesses to the channel by any station is geometrically distributed, and that each station has equal chance to access the channel in every contention period. This is significantly better than existing random-access protocols based on the binary exponential backoff algorithm, which results in large variances in inter-access delays. Our experimental results also show that the number of contention slots to resolve collisions is constant on the average, independent of the number of contending stations.

  12. Spacelab system analysis: The modified free access protocol: An access protocol for communication systems with periodic and Poisson traffic

    Science.gov (United States)

    Ingels, Frank; Owens, John; Daniel, Steven

    1989-01-01

    The protocol definition and terminal hardware for the modified free access protocol, a communications protocol similar to Ethernet, are developed. A MFA protocol simulator and a CSMA/CD math model are also developed. The protocol is tailored to communication systems where the total traffic may be divided into scheduled traffic and Poisson traffic. The scheduled traffic should occur on a periodic basis but may occur after a given event such as a request for data from a large number of stations. The Poisson traffic will include alarms and other random traffic. The purpose of the protocol is to guarantee that scheduled packets will be delivered without collision. This is required in many control and data collection systems. The protocol uses standard Ethernet hardware and software requiring minimum modifications to an existing system. The modification to the protocol only affects the Ethernet transmission privileges and does not effect the Ethernet receiver.

  13. Direct data access protocols benchmarking on DPM

    CERN Document Server

    Furano, Fabrizio; Keeble, Oliver; Mancinelli, Valentina

    2015-01-01

    The Disk Pool Manager is an example of a multi-protocol, multi-VO system for data access on the Grid that went though a considerable technical evolution in the last years. Among other features, its architecture offers the opportunity of testing its different data access frontends under exactly the same conditions, including hardware and backend software. This characteristic inspired the idea of collecting monitoring information from various testbeds in order to benchmark the behaviour of the HTTP and Xrootd protocols for the use case of data analysis, batch or interactive. A source of information is the set of continuous tests that are run towards the worldwide endpoints belonging to the DPM Collaboration, which accumulated relevant statistics in its first year of activity. On top of that, the DPM releases are based on multiple levels of automated testing that include performance benchmarks of various kinds, executed regularly every day. At the same time, the recent releases of DPM can report monitoring infor...

  14. Optimal Medium Access Protocols for Cognitive Radio Networks

    CERN Document Server

    Lai, Lifeng; Jiang, Hai; Poor, H Vincent

    2008-01-01

    This paper focuses on the design of medium access control protocols for cognitive radio networks. The scenario in which a single cognitive user wishes to opportunistically exploit the availability of empty frequency bands within parts of the radio spectrum having multiple bands is first considered. In this scenario, the availability probability of each channel is unknown a priori to the cognitive user. Hence efficient medium access strategies must strike a balance between exploring (learning) the availability probability of the channels and exploiting the knowledge of the availability probability identified thus far. For this scenario, an optimal medium access strategy is derived and its underlying recursive structure is illustrated via examples. To avoid the prohibitive computational complexity of this optimal strategy, a low complexity asymptotically optimal strategy is developed. Next, the multi-cognitive user scenario is considered and low complexity medium access protocols, which strike an optimal balanc...

  15. Ontology Based Access Control

    Directory of Open Access Journals (Sweden)

    Özgü CAN

    2010-02-01

    Full Text Available As computer technologies become pervasive, the need for access control mechanisms grow. The purpose of an access control is to limit the operations that a computer system user can perform. Thus, access control ensures to prevent an activity which can lead to a security breach. For the success of Semantic Web, that allows machines to share and reuse the information by using formal semantics for machines to communicate with other machines, access control mechanisms are needed. Access control mechanism indicates certain constraints which must be achieved by the user before performing an operation to provide a secure Semantic Web. In this work, unlike traditional access control mechanisms, an "Ontology Based Access Control" mechanism has been developed by using Semantic Web based policies. In this mechanism, ontologies are used to model the access control knowledge and domain knowledge is used to create policy ontologies.

  16. Similarity based mixed transaction concurrency control protocol

    Institute of Scientific and Technical Information of China (English)

    PAN Yi; LU Yan-sheng

    2005-01-01

    Due to the various performance requirements and data access restrictions of different types of real-time transactions, concurrency control protocols which had been designed for the systems with single type of transactions are not sufficient for mixed real-time database systems (MRTDBS), where different types of real-time transactions coexist in the systems concurrently. In this paper, a new concurrency control protocol MRTT_CC for mixed real-time transactions is proposed. The new strategy integrates with different concurrency control protocols to meet the deadline requirements of different types of real-time transactions. The data similarity concept is also explored in the new protocol to reduce the blocking time of soft real-time transactions, which increases their chances to meet the deadlines. Simulation experiments show that the new protocol has gained good performance.

  17. A comparison of Percutaneous femoral access in Endovascular Repair versus Open femoral access (PiERO) : study protocol for a randomized controlled trial

    NARCIS (Netherlands)

    Vierhout, Bastiaan P.; Saleem, Ben R.; Ott, Alewijn; van Dijl, Jan Maarten; de Kempenaer, Ties D. van Andringa; Pierie, Maurice E. N.; Bottema, Jan T.; Zeebregts, Clark J.

    2015-01-01

    Background: Access for endovascular repair of abdominal aortic aneurysms (EVAR) is obtained through surgical cutdown or percutaneously. The only devices suitable for percutaneous closure of the 20 French arteriotomies of the common femoral artery (CFA) are the Prostar (TM) and Proglide (TM) devices

  18. Android Access Control Extension

    Directory of Open Access Journals (Sweden)

    Anton Baláž

    2015-12-01

    Full Text Available The main objective of this work is to analyze and extend security model of mobile devices running on Android OS. Provided security extension is a Linux kernel security module that allows the system administrator to restrict program's capabilities with per-program profiles. Profiles can allow capabilities like network access, raw socket access, and the permission to read, write, or execute files on matching paths. Module supplements the traditional Android capability access control model by providing mandatory access control (MAC based on path. This extension increases security of access to system objects in a device and allows creating security sandboxes per application.

  19. Access Control Enforcement Testing

    OpenAIRE

    El Kateb, Donia; Elrakaiby, Yehia; Mouelhi, Tejeddine; Le Traon, Yves

    2012-01-01

    A policy-based access control architecture com- prises Policy Enforcement Points (PEPs), which are modules that intercept subjects access requests and enforce the access decision reached by a Policy Decision Point (PDP), the module implementing the access decision logic. In applications, PEPs are generally implemented manually, which can introduce errors in policy enforcement and lead to security vulnerabilities. In this paper, we propose an approach to systematically test and validate the co...

  20. Energy-efficient hybrid media access control protocol in wireless sensor networks%一种节能混合无线传感器网络MAC协议

    Institute of Scientific and Technical Information of China (English)

    刘一哲; 袁睿翕

    2011-01-01

    针对无线传感器网络的节能和网络性能流量自适应的需求,在Z-MAC协议的基础上,提出了EFHMAC协议.经过分析表明,EHMAC在保持Z-MAC高信道利用率和低延迟的同时,可以减少Z-MAC低功耗侦听机制造成的大量串音能耗以及pream-ble传输所造成的网络开销.此外,EHMAC对Z-MAC在内的TDMA类协议无法应对的非对称隐藏终端问题提出了解决方案,取得了较高的网络吞吐量和较低的端到端延迟.%This paper puts forward an Energy-efficient Hybrid Media Access Control(EHMAC) protocol in WSNs,based on Z-MAC, in order to meet requirement of power consumption and obtain network performance adaptability to burst flow. Through analysis and NS2 simulation,this paper evaluates and verifies EHMAC's low power consumption due to Low Power Listening (LPL) and maintenance of high channel utilization as Z-MAC does.Meanwhile, EHMAC can decrease the long preamble overhead.Besides,EHMAC proposes the solution to asymmetric hidden terminal problem,and gets higher throughput and lower end to end delay than TDMA category protocol,Z-MAC included.

  1. Stream Control Transmission Protocol Steganography

    CERN Document Server

    Fraczek, Wojciech; Szczypiorski, Krzysztof

    2010-01-01

    Stream Control Transmission Protocol (SCTP) is a new transport layer protocol that is due to replace TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) protocols in future IP networks. Currently, it is implemented in such operating systems like BSD, Linux, HP-UX or Sun Solaris. It is also supported in Cisco network devices operating system (Cisco IOS) and may be used in Windows. This paper describes potential steganographic methods that may be applied to SCTP and may pose a threat to network security. Proposed methods utilize new, characteristic SCTP features like multi-homing and multistreaming. Identified new threats and suggested countermeasures may be used as a supplement to RFC 5062, which describes security attacks in SCTP protocol and can induce further standard modifications.

  2. The CERN Control Protocol for power converters

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, I.; Benincasa, G.; Berrig, O.; Brun, R.; Burla, P.; Coudert, G.; Pett, J.G.; Pittin, R.; Royer, J.P.; Trofimov, N. (CERN, Geneva (Switzerland))

    1993-08-01

    The Control Protocols provide, for a class of similar devices, a unique and standard access procedure from the control system. Behavioral models have been proposed for the different kinds of Power Converters and the corresponding functionalities, with their parameters, variables and attributes have been identified. The resulting data structures have been presented using the ISO ASN.1 metalanguage, that permits universal representation independent of any computer environment. Implementations in the UNIX-based CERN accelerator control systems are under development.

  3. ACCESS Pointing Control System

    Science.gov (United States)

    Brugarolas, Paul; Alexander, James; Trauger, John; Moody, Dwight; Egerman, Robert; Vallone, Phillip; Elias, Jason; Hejal, Reem; Camelo, Vanessa; Bronowicki, Allen; O'Connor, David; Partrick, Richard; Orzechowski, Pawel; Spitter, Connie; Lillie, Chuck

    2010-01-01

    ACCESS (Actively-Corrected Coronograph for Exoplanet System Studies) was one of four medium-class exoplanet concepts selected for the NASA Astrophysics Strategic Mission Concept Study (ASMCS) program in 2008/2009. The ACCESS study evaluated four major coronograph concepts under a common space observatory. This paper describes the high precision pointing control system (PCS) baselined for this observatory.

  4. Access Protocol For An Industrial Optical Fibre LAN

    Science.gov (United States)

    Senior, John M.; Walker, William M.; Ryley, Alan

    1987-09-01

    A structure for OSI levels 1 and 2 of a local area network suitable for use in a variety of industrial environments is reported. It is intended that the LAN will utilise optical fibre technology at the physical level and a hybrid of dynamically optimisable token passing and CSMA/CD techniques at the data link (IEEE 802 medium access control - logical link control) level. An intelligent token passing algorithm is employed which dynamically allocates tokens according to the known upper limits on the requirements of each device. In addition a system of stochastic tokens is used to increase efficiency when the stochastic traffic is significant. The protocol also allows user-defined priority systems to be employed and is suitable for distributed or centralised implementation. The results of computer simulated performance characteristics for the protocol using a star-ring topology are reported which demonstrate its ability to perform efficiently with the device and traffic loads anticipated within an industrial environment.

  5. A Multiple-Reception Access Protocol with Interruptions with Mixed Priorities in CDMA Networks

    Institute of Scientific and Technical Information of China (English)

    Lu Xiaowen; Zhu Jinkang

    2003-01-01

    A novel access protocol called Multiple-Reception Access Protocol (MRAP) and its modification MRAP/WI are proposed. In this protocol, all colliding users with a common code can be identified by the base station due to the offset of arrival time Thus they can retransmit access requests under the base station's control. Furthermore new arrivals with higher priority level can interrupt the lower retransmission in order to reduce its access delay although it increases the lower priority's delay. Simulation results of MRAP and MRAP/WI are given in order to highlight the superior performance of the proposed approach.

  6. A Multiple Access Protocol for Multimedia Transmission over Wireless Networks

    CERN Document Server

    Yu, Hong

    2012-01-01

    This paper develops and evaluates the performance of an advanced multiple access protocol for transmission of full complement of multimedia signals consisting of various combinations of voice, video, data, text and images over wireless networks. The protocol is called Advanced Multiple Access Protocol for Multimedia Transmission (AMAPMT) and is to be used in the Data Link Layer of the protocol stack. The principle of operation of the protocol is presented in a number of logical flow charts. The protocol grants permission to transmit to a source on the basis of a priority scheme that takes into account a time-to-live (TTL) parameter of all the transactions, selectable priorities assigned to all the sources and relevant channel state information (CSI) in this order. Performance of the protocol is evaluated in terms of quality of service parameters like packet loss ratio (PLR), mean packet transfer delay (MPTD) and throughput. Using a simulation model based on an OPNET simulation software package does the evalua...

  7. Remote Memory Access Protocol Target Node Intellectual Property

    Science.gov (United States)

    Haddad, Omar

    2013-01-01

    The MagnetoSpheric Multiscale (MMS) mission had a requirement to use the Remote Memory Access Protocol (RMAP) over its SpaceWire network. At the time, no known intellectual property (IP) cores were available for purchase. Additionally, MMS preferred to implement the RMAP functionality with control over the low-level details of the design. For example, not all the RMAP standard functionality was needed, and it was desired to implement only the portions of the RMAP protocol that were needed. RMAP functionality had been previously implemented in commercial off-the-shelf (COTS) products, but the IP core was not available for purchase. The RMAP Target IP core is a VHDL (VHSIC Hardware Description Language description of a digital logic design suitable for implementation in an FPGA (field-programmable gate array) or ASIC (application-specific integrated circuit) that parses SpaceWire packets that conform to the RMAP standard. The RMAP packet protocol allows a network host to access and control a target device using address mapping. This capability allows SpaceWire devices to be managed in a standardized way that simplifies the hardware design of the device, as well as the development of the software that controls the device. The RMAP Target IP core has some features that are unique and not specified in the RMAP standard. One such feature is the ability to automatically abort transactions if the back-end logic does not respond to read/write requests within a predefined time. When a request times out, the RMAP Target IP core automatically retracts the request and returns a command response with an appropriate status in the response packet s header. Another such feature is the ability to control the SpaceWire node or router using RMAP transactions in the extended address range. This allows the SpaceWire network host to manage the SpaceWire network elements using RMAP packets, which reduces the number of protocols that the network host needs to support.

  8. Design of Trusted Network Connection Security Protocol and Access Control Architecture%可信网络连接安全协议与访问控制体系设计

    Institute of Scientific and Technical Information of China (English)

    王明书

    2016-01-01

    针对现阶段可信网络在连接与控制方面存在问题,分析现有可信网络实体功能、结构层次和接口协议,提出包含完整度量收集器在内的全新可信网络连接体系架构,重新设计以 EAP⁃TNC 数据包为核心的安全网络协议及访问控制体系。通过设置网络带宽、终端状态和可信等级等多项指标,对体系访问控制和连接性能进行实验测试。结论表明,可信网络连接安全协议和访问控制体系可使终端以安全可控的方式访问网络,具备良好的安全性和可用性。%In order to solve the connection and control problems of trusted network,the entity function,architecture and interface protocol of trusted network are analyzed,a new trusted network connection architecture,including the integrity measurement collector,is proposed,the security network protocol and access control architecture based on EAP⁃TNC data packet are designed.By setting specifi⁃cations such as network bandwidth,terminal state and reliability level,the performance of the basic connection and access control is test⁃ed.The result shows that based on the connection security protocol and access control architecture of trusted network, the terminal equipment can access the network in a secure and controllable way,and the security and availability are improved.

  9. Analysing Access Control Specifications

    DEFF Research Database (Denmark)

    Probst, Christian W.; Hansen, René Rydhof

    2009-01-01

    . Recent events have revealed intimate knowledge of surveillance and control systems on the side of the attacker, making it often impossible to deduce the identity of an inside attacker from logged data. In this work we present an approach that analyses the access control configuration to identify the set......When prosecuting crimes, the main question to answer is often who had a motive and the possibility to commit the crime. When investigating cyber crimes, the question of possibility is often hard to answer, as in a networked system almost any location can be accessed from almost anywhere. The most...... of credentials needed to reach a certain location in a system. This knowledge allows to identify a set of (inside) actors who have the possibility to commit an insider attack at that location. This has immediate applications in analysing log files, but also nontechnical applications such as identifying possible...

  10. Multiple access protocol for supporting multimedia services in wireless ATM networks

    DEFF Research Database (Denmark)

    Liu, Hong; Dittmann, Lars; Gliese, Ulrik Bo

    1999-01-01

    The furture broadband wireless asynchronous transfer mode (ATM) networks must provide seamless extension of multimedia services from the wireline ATM networks. This requires an effecient wireless access protocol to fulfill varying Quality-og-Service (QoS) requirements for multimedia applications....... In this paper, we propose a multiple access protocol using centralized and distributed channel access control techniques to provide QoS guarantees for multimedia services by taking advantage of the characteristics of different kinds of ATM traffics. Multimedia traffic, including constant bit rate (CBR...

  11. Development and evaluation of an "emergency access button" in Danish out-of-hours primary care: a study protocol of a randomized controlled trial.

    Science.gov (United States)

    Ebert, J F; Huibers, L; Lippert, F K; Christensen, B; Christensen, M B

    2017-05-31

    Out-of-hours (OOH) health care for acute medical problems is often challenged by long waiting time for callers in need of advice and triage. Allowing patients to bypass the OOH telephone waiting line may increase patient satisfaction and provide them with a feeling of safety. We aimed to develop an "emergency access button" enabling patients to bypass the normal telephone waiting line in out-of-hours primary care (OOH-PC) if they perceive their condition to be critical and to evaluate the effect of introducing the button in terms of patient satisfaction and their feeling of safety. All patients calling the OOH-PC in two different Danish health care regions during three months will be included in this randomized controlled trial. Data will be collected through two questionnaires developed for this study: a pop-up questionnaire on the relevance of bypassing the normal waiting line to be completed by triage professionals after patient contact and a paper/electronic questionnaire on perceived safety and satisfaction with the emergency access button to be completed by the callers. These questionnaires were developed and validated using external and internal expert feedback, focus group interviews and a two-week field test. The study will be conducted over three months with an estimated user-rate of the emergency access button of 3%. We have developed an emergency access button and we now want to investigate whether this new option will influence upon the level of satisfaction and the feeling of safety in the calling patients. Additionally, the study will reveal the assessed relevance of the decision to bypass the line by triage professionals. Registered as NCT02572115 at Clinicaltrials.gov on October 5(th) 2015.

  12. Accessibility in Public Buildings: Efficiency of Checklist Protocols.

    Science.gov (United States)

    Andersson, Jonas E; Skehan, Terry

    2016-01-01

    In Sweden, governmental agencies and bodies are required to implement a higher level of accessibility in their buildings than that stipulated by the National Building and Planning Act (PBL). The Swedish Agency for Participation (MFD, Myndigheten för delaktighet) develops holistic guidelines in order to conceptualize this higher level of accessibility. In conjunction to these guidelines, various checklist protocols have been produced. The present study focuses on the efficiency of such checklist protocols. The study revolved around the use of a checklist protocol in assessments of two buildings in Stockholm: the new head office for the National Authority for Social Insurances (ASI) and the School of Architecture at the Royal Institute of Technology (KTH). The study included three groups: Group 1 and Group 2 consisted of 50 real estate managers employed by the ASI, while Group 3 consisted of three participants in a course at the KTH. The results were similar in all of the groups. The use of the checklist protocol generated queries, which related mainly to two factors: (1) the accompanying factsheet consisted of textual explanations with no drawings, photographs or illustrations and (2) the order of the questions in the checklist protocol was difficult to correlate with the two buildings' spatial logic of accessing, egressing and making use of the built space.

  13. Physical Access Control Database -

    Data.gov (United States)

    Department of Transportation — This data set contains the personnel access card data (photo, name, activation/expiration dates, card number, and access level) as well as data about turnstiles and...

  14. Function-Based Access Control (FBAC): From Access Control Matrix to Access Control Tensor

    OpenAIRE

    Desmedt, Yvo; Shaghaghi, Arash

    2016-01-01

    Security researchers have stated that the core concept behind current implementations of access control predates the Internet. These assertions are made to pinpoint that there is a foundational gap in this field, and one should consider revisiting the concepts from the ground up. Moreover, Insider threats, which are an increasing threat vector against organizations are also associated with the failure of access control. Access control models derived from access control matrix encompass three ...

  15. Secure access control protocol for multi-source IP multicast%适用于多源IP组播的安全访问控制协议

    Institute of Scientific and Technical Information of China (English)

    王娜; 陈越; 汪斌强

    2006-01-01

    目前针对IP组播的安全访问控制问题的解决方案只是实现了对组播接收者的访问控制.为此,提出了一个广泛地适用于多源IP组播的安全访问控制协议(Multi-source Multicast Access Control,MMAC).协议通过引入专门的管理主机和管理频道实现了对组播参与者(发方和收方)及不可信路由器的安全访问控制.最后对MMAC协议的有效性和安全性进行了分析.

  16. Chapter 47: Introduction to DAL: Simple Image Access Protocol

    Science.gov (United States)

    Kwok, S.-H.; Tody, D.

    The Simple Image Access Protocol (SIAP) is a standard VO protocol for retrieving astronomical images from online archives using a web interface. A major objective of the Simple Image Access Protocol is to unify various methods to access online image repositories into a single interface that is reasonably simple for curators to implement, and at the same time flexible enough for scientists to obtain the desired images without intimate knowledge of the repositories. In practice, this means that a single SIAP software library can be used to access many SIAP services, greatly reducing the need for customized software. Similarly, the SIAP standard enables astronomical image data curators to reach a larger numbers of users without the need to provide them with new software or documentation. Since the release of version 1.0 of the SIAP specification, more than one hundred SIAP services have been registered with the NVO Registry. They provide images from the radio to infrared, optical, ultraviolet and X-ray wavebands, and from many different instruments and surveys. These SIAP services offer various degrees of capability, from direct retrieval of whole archival images, to dynamic extraction of cutouts, to on-demand computation of large image mosaics, with the returned images available in a variety of scientific and graphical output formats. SIAP provides capabilities for both data discovery and data and metadata retrieval.

  17. Controlling Access to RDF Graphs

    Science.gov (United States)

    Flouris, Giorgos; Fundulaki, Irini; Michou, Maria; Antoniou, Grigoris

    One of the current barriers towards realizing the huge potential of Future Internet is the protection of sensitive information, i.e., the ability to selectively expose (or hide) information to (from) users depending on their access privileges. Given that RDF has established itself as the de facto standard for data representation over the Web, our work focuses on controlling access to RDF data. We present a high-level access control specification language that allows fine-grained specification of access control permissions (at triple level) and formally define its semantics. We adopt an annotation-based enforcement model, where a user can explicitly associate data items with annotations specifying whether the item is accessible or not. In addition, we discuss the implementation of our framework, propose a set of dimensions that should be considered when defining a benchmark to evaluate the different access control enforcement models and present the results of our experiments conducted on different Semantic Web platforms.

  18. An anonymous access control and authenticated key exchange protocol for Mobile RFID systems in the internet of things%物联网移动RFID系统匿名访问控制认证密钥交换协议

    Institute of Scientific and Technical Information of China (English)

    朱炜玲; 喻建平

    2012-01-01

    针对物联网移动RFID系统标签隐私信息的访问控制以及用户身份隐私保护问题,本文采用身份加密和属性加密相结合的方法,建立了IB-AB-eCK安全模型,设计了基于身份及属性的认证密钥交换协议IB-AB-AKE.基于IB-AB-AKE协议,提出了移动RFID手机与信息服务器之间认证密钥交换协议,实现了在保护移动RFID手机用户身份隐私的同时,根据标签所有者定制的访问控制策略进行标签信息的访问控制认证和会话密钥交换,防止了隐私信息被非法访问.分析表明,IB-AB-AKE协议在IB-AB-eCK模型下是安全的,且在通信次数、通信量及计算量方面具有优势.%For the access control of a tag’s privacy information and the privacy protection of a user' s identity in Mobile RFID systems in the internet of things, a security model called IB-AB-eCK is introduced, and an identity-based and attribute-based authenticated key exchange (IB-AB-AKE) protocol is proposed in this paper. Based on IB-AB-AKE protocol, an authenticated key exchange scheme is then established between mobile RFID phones and information servers of mobile RFID systems in the internet of things. The scheme not only preserves the identity privacy of the user of mobile RFID phone, but also completes the authentication and agrees upon a session key for the access to the tag' s information according to the owner' s access control policy. The analyses show that IB-AB-AKE protocol is secure in IB-AB-eCK model and it has advantages for communication round, communication traffic and computing complexity.

  19. IVOA Recommendation: Simple Line Access Protocol Version 1.0

    CERN Document Server

    Salgado, Jesus; Guainazzi, Matteo; Barbarisi, Isa; Dubernet, Marie-Lise; Tody, Doug

    2011-01-01

    The Simple Line Access Protocol (SLAP) is an IVOA Data Access protocol which defines a protocol for retrieving spectral lines coming from various Spectral Line Data Collections through a uniform interface within the VO framework. These lines can be either observed or theoretical and will be typically used to identify emission or absorption features in astronomical spectra. It makes use of the Simple Spectral Line Data Model (SSLDM [1]) to characterize spectral lines through the use of uTypes [14]. Physical quantities of units are described by using the standard Units DM [15]. SLAP services can be registered in an IVOA Registry of Resources using the VOResource [12] Extension standard, having a unique ResourceIdentifier [13] in the Registry. The SLAP interface is meant to be reasonably simple to implement by service providers. A basic query will be done in a wavelength range for the different services. The service returns a list of spectral lines formatted as a VOTable. Thus, an implementation of the service m...

  20. A USER-DEPENDENT PERFECT-SCHEDULING MULTIPLE ACCESS PROTOCOL FOR VOICE-DATA INTEGRATION IN WIRELESS NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Zhou Yajian; Li Jiandong; Liu Kai

    2002-01-01

    A novel Multiple Access Control (MAC) protocol - User-dependent Perfect-scheduling Multiple Access (UPMA) protocol, which supports joint transmission of voice and data packets,is proposed. By this protocol, the bandwidth can be allocated dynamically to the uplink and downlink traffic with on-demand assignment and the transmission of Mobile Terminals (MTs)can be perfectly scheduled by means of polling. Meanwhile, a unique frame structure is designed to guarantee Quality of Service (QoS) in voice traffic supporting. An effective collision resolution algorithm is also proposed to guarantee rapid channel access for activated MTs. Finally, performance of UPMA protocol is evaluated by simulation and compared with MPRMA protocol.Simulation results show that UPMA protocol has better performance.

  1. A USER-DEPENDENT PERFECT-SCHEDULING MULTIPLE ACCESS PROTOCOL FOR VOICE-DATA INTEGRATION IN WIRELESS NETWORKDS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel Multiple Access Control(MAC) protocol-User-dependent Perfect-scheduling Multiple Access(UPMA) protocol,which supports joint transmission of voice and data packets,is proposed.By this protocol,the bandwidth can be allocated dynamically to the uplink and downlink traffic with on-demand assignment and the transmission of Mobile Terminals(MTs) can be perfectly scheduled by means of polling.Meanwhile.a unique frame stucture is designed to guarantee Quality of Service(QoS) in voice traffic supporting.An effective colision resolution algorthm is also proposed to guarantee rapid channel access for activated MTs.Finally,performance of UPMA protocol is evaluated by simulation and compared with MPRMA protocol.Simulation results show that UPMA protocol has better performance.

  2. Implementing Institute of Electrical and Electronics Engineers (IEEE) 802.11 Standard Medium Access Control Protocol for Wireless Local Area Networks (LANS) on a Laboratory Hardware Prototype

    Science.gov (United States)

    2004-06-01

    either the basic access method CSMA/CA or RTS/CTS CSMA/CA, [ZiA02] considers a third model for this analysis, a No-ACK to Figure 5. No-ACK CDMA /CA...255-6565 ext. 4445 ( DSN 785) fax: (937) 656-4055 ( DSN 986) e-mail: rusty.baldwin@afit.edu web site: http://en.afit.edu/issa/faculty

  3. A Distributed MAC Protocol for Cooperation in Random Access Networks

    CERN Document Server

    Böcherer, Georg

    2008-01-01

    WLAN is one of the most successful applications of wireless communications in daily life because of low cost and ease of deployment. The enabling technique for this success is the use of random access schemes for the wireless channel. Random access requires minimal coordination between the nodes, which considerably reduces the cost of the infrastructure. Recently, cooperative communication in wireless networks has been of increasing interest because it promises higher rates and reliability. An additional MAC overhead is necessary to coordinate the nodes to allow cooperation and this overhead can possibly cancel out the cooperative benefits. In this work, a completely distributed protocol is proposed that allows nodes in the network to cooperate via Two-Hop and Decode-and-Forward for transmitting their data to a common gateway node. It is shown that high throughput gains are obtained in terms of the individual throughput that can be guaranteed to any node in the network. These results are validated by Monte Ca...

  4. Evaluasi Pemanfaatan Wireless Internet Protocol Access System di Kota Malang

    Directory of Open Access Journals (Sweden)

    Ahmad Budi Setiawan

    2012-03-01

    Full Text Available WIPAS (Wireless Internet Protocol Accsess System adalah salah satu teknologi pita lebar (broadband yang terbaru. Teknologi tersebut dikembangkan berdasarkan model point-to-multipoint access system pada jaringan nirkabel tetap atau Fixed Wireless Access (FWA dengan memanfaatkan pita frekuensi 26-GHz. Dengan besarnya pita frekuensi yang digunakan, teknologi WIPAS dapat menampung kapasitas akses untuk lalu lintas jaringan yang sangat besar. Dalam penelitian ini akan dikaji dan dievaluasi efektifitas penggunaan teknologi WIPAS melalui kasus pemanfaatan teknologi WIPAS untuk pemberdayaan komunitas di kota Malang. Dalam penelitian ini juga akan dideskripsikan pemanfaatan teknologi WIPAS untuk melihat manfaat penggunaan teknologi tersebut. Penelitian ini dilakukan dengan metode kualitatif dengan melakukan evaluasi terhadap infrastruktur yang telah dibangun untuk melihat efektifitas pemanfaatan WIPAS. Hasil penelitian ini adalah sebuah kajian evaluatif tentang pemanfaatan WIPAS di kota Malang dan rekomendasi untuk implementasi lebih lanjut.

  5. Timing of access to secondary healthcare services for diabetes management and lower extremity amputation in people with diabetes: a protocol of a case-control study.

    LENUS (Irish Health Repository)

    Buckley, Claire M

    2013-09-03

    Lower extremity amputation (LEA) is a complication of diabetes and a marker of the quality of diabetes care. Clinical and sociodemographic determinants of LEA in people with diabetes are well known. However, the role of service-related factors has been less well explored. Early referral to secondary healthcare is assumed to prevent the occurrence of LEA. The objective of this study is to investigate a possible association between the timing of patient access to secondary healthcare services for diabetes management, as a key marker of service-related factors, and LEA in patients with diabetes.

  6. Network Access Control For Dummies

    CERN Document Server

    Kelley, Jay; Wessels, Denzil

    2009-01-01

    Network access control (NAC) is how you manage network security when your employees, partners, and guests need to access your network using laptops and mobile devices. Network Access Control For Dummies is where you learn how NAC works, how to implement a program, and how to take real-world challenges in stride. You'll learn how to deploy and maintain NAC in your environment, identify and apply NAC standards, and extend NAC for greater network security. Along the way you'll become familiar with what NAC is (and what it isn't) as well as the key business drivers for deploying NAC.Learn the step

  7. Wireless Plug and Play Control Systems: Hardware, Networks, and Protocols

    DEFF Research Database (Denmark)

    Meybodi, Soroush Afkhami

    2012-01-01

    the protocols that can fulfill the stringent requirements of P3C case studies in general. In this part, after a thorough review of available Access and Routing protocols in industrial wireless networks, a combination of a deterministic Medium Access Control (MAC) protocol and a clustered flooding-based routing...... with the control topology. Functionality of the new routing metric is verified by simulations within a flooding-based routing algorithm. The results of this research project create a clear and concise interface for the other work packages of P3C which are concluded earlier....... the damp soil medium. To overcome the challenge, all potentially useful signal propagation methods are surveyed either by reviewing the open literature, or by doing simulations, or even running experiments. At the end, Magnetic Induction (MI) is chosen as the winning candidate. New findings are achieved...

  8. Controlled Delegation Protocol in Mobile RFID Networks

    Directory of Open Access Journals (Sweden)

    Yang MingHour

    2010-01-01

    Full Text Available To achieve off-line delegation for mobile readers, we propose a delegation protocol for mobile RFID allowing its readers access to specific tags through back-end server. That is to say, reader-tag mutual authentication can be performed without readers being connected to back-end server. Readers are also allowed off-line access to tags' data. Compared with other delegation protocols, our scheme uniquely enables back-end server to limit each reader's reading times during delegation. Even in a multireader situation, our protocol can limit reading times and reading time periods for each of them and therefore makes back-end server's delegation more flexible. Besides, our protocol can prevent authorized readers from transferring their authority to the unauthorized, declining invalid access to tags. Our scheme is proved viable and secure with GNY logic; it is against certain security threats, such as replay attacks, denial of service (DoS attacks, Man-in-the-Middle attacks, counterfeit tags, and breaches of location and data privacy. Also, the performance analysis of our protocol proves that current tags can afford the computation load required in this scheme.

  9. An Access Control Protocol for Intelligent Electricity Consumption Information Acquisition Terminals%面向智能用电信息采集终端的访问控制协议

    Institute of Scientific and Technical Information of China (English)

    唐良瑞; 李荣荣; 翟峰

    2016-01-01

    In view of implementation demands of the intelligent consumption information acquisition system,radio frequency identification(RFID) technology is applied to ensure acquisition terminals management.To solve the numerous privacy and security vulnerabilities in the process of terminals authentication and information transmission in RFID systems,an access control protocol for intelligent electricity consumption information acquisition terminals is proposed.The novel protocol is divided into two stages,the terminal identity authentication and the terminal information access control.The hash function, the private key and the random key are employed to ensure the privacy and security of messages.In order to satisfy the demands of actual information collection and terminal maintenance,the reader”s operating authority over the acquisition terminal is taken into consideration,which ensures the security of the terminal sensitive information.The non-formalized method analysis indicates the new protocol can effectively resist as many as 6 kinds of attacks including the blocking attack, spoofing attack and recognizer illegal access attack,and it ensures safe access to acquisition terminals as well as legal operation of terminals information,which will improve safety protection level of the electricity consumption information acquisition system.%针对智能用电信息采集系统的建设需求,将射频识别(RFID)技术应用于采集终端全过程管理中,为解决 RFID 系统在终端身份认证及信息传输过程中存在的众多隐私安全漏洞,提出了面向智能用电信息采集终端的访问控制协议。该协议分为终端身份认证和终端信息访问控制两个阶段,采用哈希(hash)函数、私有密钥及随机密钥保证了消息的隐私性与安全性。为满足实际信息采集和终端维护需求,将识别器对采集终端的操作权限融入协议设计中,保证了终端敏感信息的安全

  10. A universal data access and protocol integration mechanism for smart home

    Science.gov (United States)

    Shao, Pengfei; Yang, Qi; Zhang, Xuan

    2013-03-01

    With the lack of standardized or completely missing communication interfaces in home electronics, there is no perfect solution to address every aspect in smart homes based on existing protocols and technologies. In addition, the central control unit (CCU) of smart home system working point-to-point between the multiple application interfaces and the underlying hardware interfaces leads to its complicated architecture and unpleasant performance. A flexible data access and protocol integration mechanism is required. The current paper offers a universal, comprehensive data access and protocol integration mechanism for a smart home. The universal mechanism works as a middleware adapter with unified agreements of the communication interfaces and protocols, offers an abstraction of the application level from the hardware specific and decoupling the hardware interface modules from the application level. Further abstraction for the application interfaces and the underlying hardware interfaces are executed based on adaption layer to provide unified interfaces for more flexible user applications and hardware protocol integration. This new universal mechanism fundamentally changes the architecture of the smart home and in some way meets the practical requirement of smart homes more flexible and desirable.

  11. ParaMED Home: A protocol for a randomised controlled trial of paramedic assessment and referral to access medical care at home

    Directory of Open Access Journals (Sweden)

    Johnston Steven

    2011-06-01

    Full Text Available Abstract Background In Australia approximately 25% of Emergency Department (ED attendances are via ambulance. ED overcrowding in Australia, as in many countries, is common. Measures to reduce overcrowding include the provision of enhanced timely primary care in the community for appropriate low risk injury and illness. Therefore paramedic assessment and referral to a community home hospital service, in preference to transfer to ED, may confer clinical and cost benefit. Methods/Design A randomised controlled trial. Consenting adult patients that call an ambulance and are assessed by paramedics as having an eligible low risk problem will be randomised to referral to ED via ambulance transfer or referral to a rapid response service that will assess and treat the patient in their own residence. The primary outcome measure is requirement for unplanned medical attention (in or out of hospital in the first 48 hours. Secondary outcomes will include a number of other clinical endpoints. A cost effectiveness analysis will be conducted. Discussion If this trial demonstrates clinical non-inferiority and cost savings associated with the primary assessment service, it will provide one means to safely address ED overcrowding. Trial Registration Australian and New Zealand Clinical Trials Registry Number 12610001064099

  12. Diagrammatization of the Transmission Control Protocol

    Directory of Open Access Journals (Sweden)

    Sabah Al-Fedaghi

    2012-09-01

    Full Text Available With the wide spread of Internet services, developers and users need a greater understanding of the technology of networking. Acquiring a clear understanding of communication protocols is an important step in understanding how a network functions; however, many protocols are complicated, and explaining them can be demanding. In addition, protocols are often explained in terms of traffic analysis and oriented toward technical staff and those already familiar with network protocols. This paper aims at proposing a diagrammatic methodology to represent protocols in general, with a focus on the Transmission Control Protocol and Secure Sockets Layer in particular. The purpose is to facilitate understanding of protocols for learning and communication purposes. The methodology is based on the notion of flow of primitive things in a system with six stages: creation, release, transfer, arrival, acceptance, and processing. Though the method presents a basic description of protocols without in-depth analysis of all aspects and mechanisms, the resultant conceptual description is a systematic specification that utilizes a few basic notions that assist in illustrating functionality and support comprehension.

  13. A slotted floor acquisition multiple access based MAC protocol for underwater acoustic networks with RTS competition

    Institute of Scientific and Technical Information of China (English)

    Liang-fang QIAN; Sen-lin ZHANG; Mei-qin LIU

    2015-01-01

    Long propagation delay, limited bandwidth, and high bit error rate pose great challenges in media access control (MAC) protocol design for underwater acoustic networks. A MAC protocol called slotted fl oor acquisition multiple access (slotted-FAMA) suitable for underwater acoustic networks is proposed and analyzed. This FAMA based protocol adds a time slot mechanism to avoid DATA packet collisions. However, slotted-FAMA is not suitable for dense networks since the multiple request-to-send (RTS) attempts problem in dense networks is serious and greatly limits the network throughput. To overcome this drawback, this paper proposes a slotted-FAMA based MAC protocol for underwater acoustic networks, called RC-SFAMA. RC-SFAMA introduces an RTS competition mechanism to keep the network from high frequency of backoff caused by the multiple RTS attempts problem. Via the RTS competition mechanism, useful data transmission can be completed successfully when the situation of multiple RTS attempts occurs. Simulation results show that RC-SFAMA increases the network throughput efficiency as compared with slotted-FAMA, and minimizes the energy consumption.

  14. Efficient Controlled Quantum Secure Direct Communication Protocols

    Science.gov (United States)

    Patwardhan, Siddharth; Moulick, Subhayan Roy; Panigrahi, Prasanta K.

    2016-07-01

    We study controlled quantum secure direct communication (CQSDC), a cryptographic scheme where a sender can send a secret bit-string to an intended recipient, without any secure classical channel, who can obtain the complete bit-string only with the permission of a controller. We report an efficient protocol to realize CQSDC using Cluster state and then go on to construct a (2-3)-CQSDC using Brown state, where a coalition of any two of the three controllers is required to retrieve the complete message. We argue both protocols to be unconditionally secure and analyze the efficiency of the protocols to show it to outperform the existing schemes while maintaining the same security specifications.

  15. A study on the media access control protocol for distributed multi-hop underwater acoustic network%分布式多跳水声通信网络的媒质控制协议研究

    Institute of Scientific and Technical Information of China (English)

    李霞; 杨文; 苏阳

    2013-01-01

    Underwater Acoustic Network(UAN)technology has become attractive to the researchers in the field of underwater acoustic communication in recent years[1~4].One of the key technologies is the design of media access control(MAC)protocol.The focus of this paper is to design an energy and throughput efficient MAC protocol for multi-hop and long range acoustic sensor networks.A multi-hop T-Lohi protocol (MT-Lohi)is designed,which extends the T-Lohi protocol from single-hop networks to multi-hop networks by introducing dynamic contention round,pseudo tone,priority-based contention,new contenders counting mechanism.In order to gain a balance between good channel utilization and low probability of packet loss,the length of the duration of contention round is modified also.Simulation under OPNET platform is carried out to evaluate the performance in throughput,packet loss rate and fairness,and to verify the effectiveness of dynamic contention round.%水声通信网络由于可以弥补传统海洋探测技术的不足,在海洋信息采集、环境监测、灾难预报、辅助导航、水声反潜等民用、军事领域有诸多重要应用.因此,组网技术也成为近年来水声通信领域的研究热点之一.其中数据链路层的媒质控制协议关系到信道资源的有效分配及网络性能.结合能量及网络吞吐量效率因素,本文设计了一种用于分布式远距离多跳水声通信网络的媒质控制协议协议.已有的的新性能的水声调制解调器并没有开发相应的低功耗网络媒质控制协议.有人提出了一类分布式能量有效的竞争媒质控制协议,称为Tone-Lohi (T-Lohi)协议,该协议采用了信道预约机制,共有三个类型:时间同步的T-Lohi协议、保守非时间同步T-Lohi协议及主动非时间同步T-Lohi协议.本文在分析该类协议的基础上讨论了分布式多跳水声通信网络的竞争型媒质控制协议.设计了多跳式的T-Lohi协议,通过采用动态竞争回

  16. Modelling high data rate communication network access protocol

    Science.gov (United States)

    Khanna, S.; Foudriat, E. C.; Paterra, Frank; Maly, Kurt J.; Overstreet, C. Michael

    1990-01-01

    Modeling of high data rate communication systems is different from the low data rate systems. Three simulations were built during the development phase of Carrier Sensed Multiple Access/Ring Network (CSMA/RN) modeling. The first was a model using SIMCRIPT based upon the determination and processing of each event at each node. The second simulation was developed in C based upon isolating the distinct object that can be identified as the ring, the message, the node, and the set of critical events. The third model further identified the basic network functionality by creating a single object, the node which includes the set of critical events which occur at the node. The ring structure is implicit in the node structure. This model was also built in C. Each model is discussed and their features compared. It should be stated that the language used was mainly selected by the model developer because of his past familiarity. Further the models were not built with the intent to compare either structure or language but because the complexity of the problem and initial results contained obvious errors, so alternative models were built to isolate, determine, and correct programming and modeling errors. The CSMA/RN protocol is discussed in sufficient detail to understand modeling complexities. Each model is described along with its features and problems. The models are compared and concluding observations and remarks are presented.

  17. Flexible access control for dynamic collaborative environments

    NARCIS (Netherlands)

    Dekker, Mari Antonius Cornelis

    2009-01-01

    Access control is used in computer systems to control access to confidential data. In this thesis we focus on access control for dynamic collaborative environments where multiple users and systems access and exchange data in an ad hoc manner. In such environments it is difficult to protect confident

  18. Operational protocols for controlling accelerator equipment

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, R.; Baribaud, G.; Benincasa, G.P.; Burla, P.; Casalegno, L.; Coudert, G.; Gelato, G.; Kuhn, H.K.; Saban, R.; Spinks, A. (European Organization for Nuclear Research, Geneva (Switzerland). LEP Div.)

    1990-08-01

    The equipment used to operate an accelerator is varied. However, the different devices may be divided into a limited number of classes for which operational protocols can be defined. Operational protocols permit: (i) a uniform operation, (ii) a clear definition of responsibility between the various specialists, (iii) independent development of programs and use of the most appropriate technology, (iv) the change of hardware and the transportability of software, and (v) the fabrication of devices by industry for general use. An operational protocol should be independent of any given control system and it must not be confused with a transmission protocol. As a first step, one defines an operational model of the device to be controlled. The model must represent a high-level description of the device as seen by the user. It will be characterized by a set of parameters and a set of rules. Although the particular requirements of specialists are not included in the operational protocol, allowances should be made for them. Emphasis will be placed on studies carried out on power converters and beam instrumentation. A general-purpose control message architecture is reported. (orig.).

  19. Operational protocols for controlling accelerator equipment

    Science.gov (United States)

    Bailey, R.; Baribaud, G.; Benincasa, G. P.; Burla, P.; Casalegno, L.; Coudert, G.; Gelato, G.; Kuhn, H. K.; Saban, R.; Spinks, A.

    1990-08-01

    The equipment used to operate an accelerator is varied. However, the different devices may be divided into a limited number of classes for which operational protocols can be defined. Operational protocols permit: (i) a uniform operation, (ii) a clear definition of responsibility between the various specialists, (iii) independent development of programs and use of the most appropriate technology, (iv) the change of hardware and the transportability of software, and (v) the fabrication of devices by industry for general use. An operational protocol should be independent of any given control system and it must not be confused with a transmission protocol. As a first step, one defines an operational model of the device to be controlled. The model must represent a high-level description of the device as seen by the user. It will be characterized by a set of parameters and a set of rules. Although the particular requirements of specialists are not included in the operational protocol, allowances should be made for them. Emphasis will be placed on studies carried out on power converters and beam instrumentation. A general-purpose control message architecture is reported.

  20. The ACCESS study a Zelen randomised controlled trial of a treatment package including problem solving therapy compared to treatment as usual in people who present to hospital after self-harm: study protocol for a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Parag Varsha

    2011-05-01

    Full Text Available Abstract Background People who present to hospital after intentionally harming themselves pose a common and important problem. Previous reviews of interventions have been inconclusive as existing trials have been under powered and done on unrepresentative populations. These reviews have however indicated that problem solving therapy and regular written communications after the self-harm attempt may be an effective treatment. This protocol describes a large pragmatic trial of a package of measures which include problem solving therapy, regular written communication, patient support, cultural assessment, improved access to primary care and a risk management strategy in people who present to hospital after self-harm using a novel design. Methods We propose to use a double consent Zelen design where participants are randomised prior to giving consent to enrol a large representative cohort of patients. The main outcome will be hospital attendance following repetition of self-harm, in the 12 months after recruitment with secondary outcomes of self reported self-harm, hopelessness, anxiety, depression, quality of life, social function and hospital use at three months and one year. Discussion A strength of the study is that it is a pragmatic trial which aims to recruit large numbers and does not exclude people if English is not their first language. A potential limitation is the analysis of the results which is complex and may underestimate any effect if a large number of people refuse their consent in the group randomised to problem solving therapy as they will effectively cross over to the treatment as usual group. However the primary analysis is a true intention to treat analysis of everyone randomised which includes both those who consent and do not consent to participate in the study. This provides information about how the intervention will work in practice in a representative population which is a major advance in this study compared to what has

  1. Task Delegation Based Access Control Models for Workflow Systems

    Science.gov (United States)

    Gaaloul, Khaled; Charoy, François

    e-Government organisations are facilitated and conducted using workflow management systems. Role-based access control (RBAC) is recognised as an efficient access control model for large organisations. The application of RBAC in workflow systems cannot, however, grant permissions to users dynamically while business processes are being executed. We currently observe a move away from predefined strict workflow modelling towards approaches supporting flexibility on the organisational level. One specific approach is that of task delegation. Task delegation is a mechanism that supports organisational flexibility, and ensures delegation of authority in access control systems. In this paper, we propose a Task-oriented Access Control (TAC) model based on RBAC to address these requirements. We aim to reason about task from organisational perspectives and resources perspectives to analyse and specify authorisation constraints. Moreover, we present a fine grained access control protocol to support delegation based on the TAC model.

  2. Controlling Access to Suicide Means

    Directory of Open Access Journals (Sweden)

    Miriam Iosue

    2011-12-01

    Full Text Available Background: Restricting access to common means of suicide, such as firearms, toxic gas, pesticides and other, has been shown to be effective in reducing rates of death in suicide. In the present review we aimed to summarize the empirical and clinical literature on controlling the access to means of suicide. Methods: This review made use of both MEDLINE, ISI Web of Science and the Cochrane library databases, identifying all English articles with the keywords “suicide means”, “suicide method”, “suicide prediction” or “suicide prevention” and other relevant keywords. Results: A number of factors may influence an individual’s decision regarding method in a suicide act, but there is substantial support that easy access influences the choice of method. In many countries, restrictions of access to common means of suicide has lead to lower overall suicide rates, particularly regarding suicide by firearms in USA, detoxification of domestic and motor vehicle gas in England and other countries, toxic pesticides in rural areas, barriers at jumping sites and hanging, by introducing “safe rooms” in prisons and hospitals. Moreover, decline in prescription of barbiturates and tricyclic antidepressants (TCAs, as well as limitation of drugs pack size for paracetamol and salicylate has reduced suicides by overdose, while increased prescription of SSRIs seems to have lowered suicidal rates. Conclusions: Restriction to means of suicide may be particularly effective in contexts where the method is popular, highly lethal, widely available, and/or not easily substituted by other similar methods. However, since there is some risk of means substitution, restriction of access should be implemented in conjunction with other suicide prevention strategies.

  3. Service-Oriented Access Control

    Science.gov (United States)

    2014-09-01

    Language HTTP Hypertext Transfer Protocol HTTPS Secure Hypertext Transfer Protocol IDS intrusion detection system IEEE Institute for Electrical and...so we limit our focus to a subset of these services in order to convey the basic concepts of the framework. Specifically, we focus on Hypertext ...Transfer Protocol (HTTP), Secure Hypertext Transfer Protocol (HTTPS), and Internet Relay Chat (IRC). We also constrain our work in terms of network size

  4. Access Request Trustworthiness in Weighted Access Control Framework

    Institute of Scientific and Technical Information of China (English)

    WANG Lun-wei; LIAO Xiang-ke; WANG Huai-min

    2005-01-01

    Weighted factor is given to access control policies to express the importance of policy and its effect on access control decision. According to this weighted access control framework, a trustworthiness model for access request is also given. In this model, we give the measure of trustworthiness factor to access request, by using some idea of uncertainty reasoning of expert system, present and prove the parallel propagation formula of request trustworthiness factor among multiple policies, and get the final trustworthiness factor to decide whether authorizing. In this model, authorization decision is given according to the calculation of request trustworthiness factor, which is more understandable, more suitable for real requirement and more powerful for security enhancement than traditional methods. Meanwhile the finer access control granularity is another advantage.

  5. Physiological, Behavioral, and Scientific Impact of Different Fluid Control Protocols in the Rhesus Macaque (Macaca mulatta)

    Science.gov (United States)

    Bertrand, Henri; Mindus, Claire; Flecknell, Paul

    2016-01-01

    Abstract Rhesus macaques are an important model in behavioral neuroscience due to their advanced cognitive abilities. To motivate animals to engage in complex tasks, fluid rewards, in conjunction with fluid control protocols, are often used. The impact of these protocols on animal welfare is controversial. We compared two fluid control protocols against a protocol providing free access to water and evaluated the impacts on physiological states of hydration, behavioral measures of welfare, and scientific output. Blood physiology did not significantly differ between any of the protocols, and urine measures were indicative of well functioning, healthy kidneys. Changes in behaviors were limited, the main one being an increase in motivation to drink on the stricter fluid control protocol, and improved task performance early in the week. Overall, fluid control protocols had little measurable impact on the welfare of rhesus macaques while ensuring that scientific data of high quality could be obtained. PMID:27679812

  6. A DUAL RESERVATION CDMA-BASED MAC PROTOCOL WITH POWER CONTROL FOR AD HOC NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Jia Min; Chen Huimin; Yuan Yuhua

    2007-01-01

    This paper proposes a new multi-channel Medium Access Control (MAC) protocol named as Dual Reservation Code Division Multiple Access (CDMA) based MAC protocol with Power Control (DRCPC). The code channel is divided into common channel, broadcast channel and several data channels. And dynamic power control mechanism is implemented to reduce near-far interference. Compared with IEEE 802.11 Distributed Coordination Function (DCF) protocol, the results show that the proposed mechanism improves the average throughput and limits the transmission delay efficiently.

  7. Efficient Controlled Quantum Secure Direct Communication Protocols

    OpenAIRE

    Patwardhan, Siddharth; Moulick, Subhayan Roy; Prasanta K. Panigrahi

    2015-01-01

    We study controlled quantum secure direct communication (CQSDC), a cryptographic scheme where a sender can send a secret bit-string to an intended recipient, without any secure classical channel, who can obtain the complete bit-string only with the permission of a controller. We report an efficient protocol to realize CQSDC using Cluster state and then go on to construct a (2-3)-CQSDC using Brown state, where a coalition of any two of the three controllers is required to retrieve the complete...

  8. Comparison of High Speed Congestion Control Protocols

    Directory of Open Access Journals (Sweden)

    Jawhar Ben Abed

    2012-10-01

    Full Text Available Congestion control limits the quantity of information input at a rate less important than that of thetransmission one to ensure good performance as well as protect against overload and blocking of thenetwork. Researchers have done a great deal of work on improving congestion control protocols,especially on high speed networks.In this paper, we will be studying the congestion control alongside low and high speed congestion controlprotocols. We will be also simulating, evaluating, and comparing eight of high speed congestion controlprotocols : Bic TCP, Cubic TCP, Hamilton TCP, HighSpeed TCP, Illinois TCP, Scalable TCP,Compound TCP and YeAH TCP, with multiple flows.

  9. Explanation of the Nagoya Protocol on Access and Benefit Sharing and its implication for microbiology.

    Science.gov (United States)

    Smith, David; da Silva, Manuela; Jackson, Julian; Lyal, Christopher

    2017-03-01

    Working with genetic resources and associated data requires greater attention since the Nagoya Protocol on Access and Benefit Sharing (ABS) came into force in October 2014. Biologists must ensure that they have legal clarity in how they can and cannot use the genetic resources on which they carry out research. Not only must they work within the spirit in the Convention on Biological Diversity (https://www.cbd.int/convention/articles/default.shtml?a=cbd-02) but also they may have regulatory requirements to meet. Although the Nagoya Protocol was negotiated and agreed globally, it is the responsibility of each country that ratifies it to introduce their individual implementing procedures and practices. Many countries in Europe, such as the UK, have chosen not to put access controls in place at this time, but others already have laws enacted providing ABS measures under the Convention on Biological Diversity or specifically to implement the Nagoya Protocol. Access legislation is in place in many countries and information on this can be found at the ABS Clearing House (https://absch.cbd.int/). For example, Brazil, although not a Party to the Nagoya Protocol at the time of writing, has Law 13.123 which entered into force on 17 November 2015, regulated by Decree 8.772 which was published on 11 May 2016. In this case, export of Brazilian genetic resources is not allowed unless the collector is registered in the National System for Genetic Heritage and Associated Traditional Knowledge Management (SisGen). The process entails that a foreign scientist must first of all be registered working with someone in Brazil and have authorization to collect. The enactment of European Union Regulation po. 511/2014 implements Nagoya Protocol elements that govern compliance measures for users and offers the opportunity to demonstrate due diligence in sourcing their organisms by selecting from holdings of 'registered collections'. The UK has introduced a Statutory Instrument that puts in

  10. Dynamic Characteristics of Explicit Control Protocol

    Institute of Scientific and Technical Information of China (English)

    CHENG Shuang-mei; LI Jian-hua; GUO Chuan-xiong

    2008-01-01

    The dynamic characteristics of eplicit control protocol (XCP) were investigated with single bottle-neck on the microscopic time-scale. Analysis and simulation results show that the bandwidth utilization of an XCP bottleneck link converges to 1 at exponential rate, persistent congestion cannot occur at the bottleneck link, and throughput of an arbitrary subset of XCP flows at the bottleneck link converges to its fair share in exponential rate. The XCP has high bandwidth utilization and good fairness properties.

  11. Advertisement-Based Energy Efficient Medium Access Protocols for Wireless Sensor Networks

    Science.gov (United States)

    Ray, Surjya Sarathi

    One of the main challenges that prevents the large-scale deployment of Wireless Sensor Networks (WSNs) is providing the applications with the required quality of service (QoS) given the sensor nodes' limited energy supplies. WSNs are an important tool in supporting applications ranging from environmental and industrial monitoring, to battlefield surveillance and traffic control, among others. Most of these applications require sensors to function for long periods of time without human intervention and without battery replacement. Therefore, energy conservation is one of the main goals for protocols for WSNs. Energy conservation can be performed in different layers of the protocol stack. In particular, as the medium access control (MAC) layer can access and control the radio directly, large energy savings is possible through intelligent MAC protocol design. To maximize the network lifetime, MAC protocols for WSNs aim to minimize idle listening of the sensor nodes, packet collisions, and overhearing. Several approaches such as duty cycling and low power listening have been proposed at the MAC layer to achieve energy efficiency. In this thesis, I explore the possibility of further energy savings through the advertisement of data packets in the MAC layer. In the first part of my research, I propose Advertisement-MAC or ADV-MAC, a new MAC protocol for WSNs that utilizes the concept of advertising for data contention. This technique lets nodes listen dynamically to any desired transmission and sleep during transmissions not of interest. This minimizes the energy lost in idle listening and overhearing while maintaining an adaptive duty cycle to handle variable loads. Additionally, ADV-MAC enables energy efficient MAC-level multicasting. An analytical model for the packet delivery ratio and the energy consumption of the protocol is also proposed. The analytical model is verified with simulations and is used to choose an optimal value of the advertisement period

  12. An Access Control Framework for Reflective Middleware

    Institute of Scientific and Technical Information of China (English)

    Gang Huang; Lian-Shan Sun

    2008-01-01

    Reflective middleware opens up the implementation details of middleware platform and applications at runtime for improving the adaptability of middleware-based systems. However, such openness brings new challenges to access control of the middleware-based systems.Some users can access the system via reflective entities, which sometimes cannot be protected by access control mechanisms of traditional middleware. To deliver high adaptability securely, reflective middleware should be equipped with proper access control mechanisms for potential access control holes induced by reflection. One reason of integrating these mechanisms in reflective middleware is that one goal of reflective middleware is to equip applications with reflection capabilities as transparent as possible. This paper studies how to design a reflective J2EE middlewarePKUAS with access control in mind. At first, a computation model of reflective system is built to identify all possible access control points induced by reflection. Then a set of access control mechanisms, including the wrapper of MBeans and a hierarchy of Java class loaders, are equipped for controlling the identified access control points. These mechanisms together with J2EE access control mechanism form the access control framework for PKUAS. The paper evaluates the security and the performance overheads of the framework in quality and quantity.

  13. Analysis of the LTE Access Reservation Protocol for Real-Time Traffic

    DEFF Research Database (Denmark)

    Thomsen, Henning; Kiilerich Pratas, Nuno; Stefanovic, Cedomir;

    2013-01-01

    LTE is increasingly seen as a system for serving real-time Machine-to-Machine (M2M) communication needs. The asynchronous M2M user access in LTE is obtained through a two-phase access reservation protocol (contention and data phase). Existing analysis related to these protocols is based on the fo......LTE is increasingly seen as a system for serving real-time Machine-to-Machine (M2M) communication needs. The asynchronous M2M user access in LTE is obtained through a two-phase access reservation protocol (contention and data phase). Existing analysis related to these protocols is based...... of available data resources caused by variable load, and (2) detection of collisions in contention phase may not be possible. All of this affects transmission of real-time M2M traffic, where data packets have to be sent within a deadline and may have only one contention opportunity. We analyze the features...

  14. Efficient Access Control in Multimedia Social Networks

    Science.gov (United States)

    Sachan, Amit; Emmanuel, Sabu

    Multimedia social networks (MMSNs) have provided a convenient way to share multimedia contents such as images, videos, blogs, etc. Contents shared by a person can be easily accessed by anybody else over the Internet. However, due to various privacy, security, and legal concerns people often want to selectively share the contents only with their friends, family, colleagues, etc. Access control mechanisms play an important role in this situation. With access control mechanisms one can decide the persons who can access a shared content and who cannot. But continuously growing content uploads and accesses, fine grained access control requirements (e.g. different access control parameters for different parts in a picture), and specific access control requirements for multimedia contents can make the time complexity of access control to be very large. So, it is important to study an efficient access control mechanism suitable for MMSNs. In this chapter we present an efficient bit-vector transform based access control mechanism for MMSNs. The proposed approach is also compatible with other requirements of MMSNs, such as access rights modification, content deletion, etc. Mathematical analysis and experimental results show the effectiveness and efficiency of our proposed approach.

  15. A Trusted Host's Authentication Access and Control Model Faced on User Action

    Institute of Scientific and Technical Information of China (English)

    ZHANG Miao; XU Guoai; HU Zhengming; YANG Yixian

    2006-01-01

    The conception of trusted network connection (TNC) is introduced, and the weakness of TNC to control user's action is analyzed. After this, the paper brings out a set of secure access and control model based on access, authorization and control, and related authentication protocol. At last the security of this model is analyzed. The model can improve TNC's security of user control and authorization.

  16. Joint estimation and contention-resolution protocol for wireless random access

    DEFF Research Database (Denmark)

    Stefanovic, Cedomir; Trillingsgaard, Kasper Fløe; Kiilerich Pratas, Nuno;

    2013-01-01

    We propose a contention-based random-access protocol, designed for wireless networks where the number of users is not a priori known. The protocol operates in rounds divided into equal-duration slots, performing at the same time estimation of the number of users and resolution of their transmissi...

  17. WIRELESS ADHOC MULTI ACCESS NETWORKS OPTIMIZATION USING OSPF ROUTING PROTOCOL BASED ON CISCO DEVICES

    Directory of Open Access Journals (Sweden)

    Mohamed E. Khedr

    2015-03-01

    Full Text Available One of the most attractive field for research for researchers and authors so the Wireless adhoc networks. So, this paper will describe the background and basic features of Open Short Path First (OSPF routing protocol due to multi-access networks. Explaining and practice on the OSPF configuration commands. Describe, modify and calculate the metric (Cost used by OSPF due to adhoc networks. Illustrating the Election parameters made by DR/BDR (Designated and Back Designated Routers used in multi-access wireless networks. This paper will use OSPF routing protocol because of its average administrative distance with all routing protocols.

  18. Access Control with RFID in the Internet of Things

    DEFF Research Database (Denmark)

    Jensen, Steffen Elstrøm Holst; Jacobsen, Rune Hylsberg

    2013-01-01

    , to the Internet is suggested. The solution uses virtual representations of objects by using low-cost, passive RFID tags to give objects identities on the Internet. A prototype that maps an RFID identity into an IPv6 address is constructed. It is illustrated how this approach can be used in access control systems...... based on open network protocols and packet filtering. The solution includes a novel RFID reader architecture that supports the internetworking of components of a future access control system based on network layer technology....

  19. A pilot cluster randomised controlled trial to investigate the addition of direct access to physiotherapy to usual GP-led primary care for adults with musculoskeletal pain: the STEMS pilot trial protocol (ISRCTN23378642).

    Science.gov (United States)

    Bishop, Annette; Tooth, Stephanie; Protheroe, Joanne; Salisbury, Chris; Ogollah, Reuben O; Jowett, Sue; Hay, Elaine M; Foster, Nadine E

    2015-01-01

    Musculoskeletal problems are common, accounting for up to 30 % of general practitioner (GP) consultations and are a major cause of chronic disability worldwide. Demand for health care for musculoskeletal conditions is likely to continue to rise given the ageing population and the increasing impact of these common painful conditions. Physiotherapists are well equipped to deliver evidence-based management for these conditions. Direct access allows patients to access physiotherapy without seeing their GP or another referring practitioner first; however, for most patients in the UK, access to National Health Service physiotherapy is controlled through GP referral. The aim of this pilot, pragmatic, cluster trial is to assess the feasibility of a future large trial to compare the clinical and cost-effectiveness of the additional offer of direct access to physiotherapy versus continuing with usual GP-led primary care alone for adults with common musculoskeletal problems. The pilot will focus on process outcomes to assess feasibility, although performance of the likely outcomes of a main trial will also be assessed. This is a two-arm parallel, cluster RCT where GP practices are the units of randomisation (the clusters), yet data are collected from individual patients with musculoskeletal problems (the participants). A direct access service will be set up in the participating physiotherapy service to provide the option of direct access to patients of the intervention arm practices. Inclusion criteria are broad to reflect the 'real-world' operation of an NHS physiotherapy direct access service for patients with musculoskeletal pain. Data collection will be through patient self-reported questionnaires at baseline, 2, 6 and 12 months and medical record review. No previous trials have been conducted into direct access to physiotherapy for patients with musculoskeletal problems. The strengths of the STEMS pilot trial are its size, the length of follow-up, and collection of

  20. Managing Delegation in Access Control Models

    CERN Document Server

    Ghorbel-Talbi, Meriam Ben; Cuppens-Boulahia, Nora; Bouhoula, Adel; 10.1109/ADCOM.2007.105

    2010-01-01

    In the field of access control, delegation is an important aspect that is considered as a part of the administration mechanism. Thus, a complete access control must provide a flexible administration model to manage delegation. Unfortunately, to our best knowledge, there is no complete model for describing all delegation requirements for role-based access control. Therefore, proposed models are often extended to consider new delegation characteristics, which is a complex task to manage and necessitate the redefinition of these models. In this paper we describe a new delegation approach for extended role-based access control models. We show that our approach is flexible and is sufficient to manage all delegation requirements.

  1. A novel multipriority reservation protocol for plastic optical fiber access network

    Institute of Scientific and Technical Information of China (English)

    Ning Zhang(张宁); Rongjin Yu(于荣金)

    2003-01-01

    In this papcr, a novel multipriority reservation protocol for plastic optical fiber access network based onoptical code division multiplexing access (OCDMA) technology is proposed. Conventional OCDMA systemonly allows finite units to transmit and access simultaneously according to the number of channels. Theprotocol is proposed to resolve this problem. By using the reservation scheme and a distributed arbitrationalgorithm, channel collision and destination conflict can be avoided. The protocol can efficiently supportthe transmission of multimedia messages that require the different time-delays. At the same time, eachoptical network unit is equipped with a fixed optical encoder/decoder that is always tuned to channel forcontrol and the tunable optical encoder/decoder that is tuned to any of channel for data. The networkthroughput and average delay have been investigated by numerical analysis and simulation experiments.It is shown that the multipriority reservation protocol in this POF access network based on OCDMAtechnology is valid and efficient.

  2. A New Key-lock Method for User Authentication and Access Control

    Institute of Scientific and Technical Information of China (English)

    JI Dongyao; ZHANG Futai; WANG Yumin

    2001-01-01

    We propose a new key-lock methodfor user authentication and access control based onChinese remainder theorem, the concepts of the ac-cess control matrix, key-lock-pair, time stamp, and the NS public key protocol. Our method is dynamicand needs a minimum amount of computation in thesense that it only updates at most one key/lock foreach access request. We also demonstrate how an au-thentication protocol can be integrated into the ac-cess control method. By applying a time stamp, themethod can not only withstand replay attack, butalso strengthen the authenticating mechanism, whichcould not be achieved simultaneously in previous key-lock methods.

  3. FODA: a novel efficient multiple access protocol for highly dynamic self-organizing networks

    Science.gov (United States)

    Li, Hantao; Liu, Kai; Zhang, Jun

    2005-11-01

    Based on the concept of contention reservation for polling transmission and collision prevention strategy for collision resolution, a fair on-demand access (FODA) protocol for supporting node mobility and multihop architecture in highly dynamic self-organizing networks is proposed. In the protocol, a distributed clustering network architecture formed by self-organizing algorithm and a main idea of reserving channel resources to get polling service are adopted, so that the hidden terminal (HT) and exposed terminal (ET) problems existed in traffic transmission due to multihop architecture and wireless transmission can be eliminated completely. In addition, an improved collision prevention scheme based on binary countdown algorithm (BCA), called fair collision prevention (FCP) algorithm, is proposed to greatly eliminate unfair phenomena existed in contention access of newly active ordinary nodes and completely resolve access collisions. Finally, the performance comparison of the FODA protocol with carrier sense multiple access with collision avoidance (CSMA/CA) and polling protocols by OPNET simulation are presented. Simulation results show that the FODA protocol can overcome the disadvantages of CSMA/CA and polling protocols, and achieve higher throughput, lower average message delay and less average message dropping rate.

  4. Rate Control Protocol for Fast Flows: A Survey

    Directory of Open Access Journals (Sweden)

    Mr. Gaganpreet Singh,

    2014-01-01

    Full Text Available In today’s world, congestion control is a main objective to maximize fairness, utilization and throughput of the Internet. Every protocol has its own features to handle the congestion. The most widely used protocol over the Internet is Transfer Control Protocol. It aims at reliable and in order delivery of bytes to the higher layer and it also protect the network from congestive control. Other congestion control protocols are XCP and RCP. These new protocols are advancement over TCP. We study new congestion control protocol like Rate Control Protocol that make flows complete frequently as compared to TCP and other version of TCP and XCP. In this paper we have presented a comparison between TCP, XCP and RCP, which shows that RCP is a superior choice to use over the Internet to make flows complete quickly

  5. Proximity Displays for Access Control

    Science.gov (United States)

    Vaniea, Kami

    2012-01-01

    Managing access to shared digital information, such as photographs and documents. is difficult for end users who are accumulating an increasingly large and diverse collection of data that they want to share with others. Current policy-management solutions require a user to proactively seek out and open a separate policy-management interface when…

  6. Identity Establishment and Capability Based Access Control (IECAC) Scheme for Internet of Things

    DEFF Research Database (Denmark)

    Mahalle, Parikshit N.; Anggorojati, Bayu; Prasad, Neeli R.

    2012-01-01

    and denial of service attacks, the concept of capability for access control is introduced. This paper presents Identity establishment and capability based access control (IECAC) protocol using ECC (Elliptical Curve Cryptography) for IoT along with protocol evaluation, which protect against the aforementioned......Internet of Things (IoT) become discretionary part of everyday life and could befall a threat if security is not considered before deployment. Authentication and access control in IoT is equally important to establish secure communication between devices. To protect IoT from man in middle, replay...... attacks. The protocol evaluation by using security protocol verification tool shows that IECAC is secure against these attacks. This paper also discusses performance analysis of the protocol in terms of computational time and compared with other existing solutions....

  7. A Survey on Coverage Control Protocols in Wireless Sensor Networks

    OpenAIRE

    2013-01-01

    Coverage control algorithms play an important role in Wireless sensor network. Effective coverage control algorithms sense its coverage area with less energy spent. These coverage control models falls under various approaches like clustering, evolutionary, mobility based approaches. This paper makes a detailed survey on coverage control protocols coming under various classifications. In addition, it also discussed several protocols working mechanism with its evaluation metrics.

  8. Multihop Medium Access Control for WSNs: An Energy Analysis Model

    Directory of Open Access Journals (Sweden)

    Haapola Jussi

    2005-01-01

    Full Text Available We present an energy analysis technique applicable to medium access control (MAC and multihop communications. Furthermore, the technique's application gives insight on using multihop forwarding instead of single-hop communications. Using the technique, we perform an energy analysis of carrier-sense-multiple-access (CSMA- based MAC protocols with sleeping schemes. Power constraints set by battery operation raise energy efficiency as the prime factor for wireless sensor networks. A detailed energy expenditure analysis of the physical, the link, and the network layers together can provide a basis for developing new energy-efficient wireless sensor networks. The presented technique provides a set of analytical tools for accomplishing this. With those tools, the energy impact of radio, MAC, and topology parameters on the network can be investigated. From the analysis, we extract key parameters of selected MAC protocols and show that some traditional mechanisms, such as binary exponential backoff, have inherent problems.

  9. Access control and personal identification systems

    CERN Document Server

    Bowers, Dan M

    1988-01-01

    Access Control and Personal Identification Systems provides an education in the field of access control and personal identification systems, which is essential in selecting the appropriate equipment, dealing intelligently with vendors in purchases of the equipment, and integrating the equipment into a total effective system. Access control devices and systems comprise an important part of almost every security system, but are seldom the sole source of security. In order for the goals of the total system to be met, the other portions of the security system must also be well planned and executed

  10. An Efficient Secure Real-Time Concurrency Control Protocol

    Institute of Scientific and Technical Information of China (English)

    XIAO Yingyuan; LIU Yunsheng; CHEN Xiangyang

    2006-01-01

    Secure real-time databases must simultaneously satisfy two requirements in guaranteeing data security and minimizing the missing deadlines ratio of transactions. However, these two requirements can conflict with each other and achieve one requirement is to sacrifice the other. This paper presents a secure real-time concurrency control protocol based on optimistic method. The concurrency control protocol incorporates security constraints in a real-time optimistic concurrency control protocol and makes a suitable tradeoff between security and real-time requirements by introducing secure influence factor and real-time influence factor. The experimental results show the concurrency control protocol achieves data security without degrading real-time performance significantly.

  11. Internetworking with Internet Protocol (IP) and Transmission Control Protocol (TCP) within the Military

    OpenAIRE

    Eikenberg, Bruce R.

    1990-01-01

    Approved for public release; distribution is unlimited. The backbone of the internetworking technology widely used by the military, as well as many civilian installations, is commonly referred to as TCP/IP. Transmission Control Protocol (TCP) and Internet Protocol (IP) are the two standard communication protocols from which TCP/IP receives its name. By utilizing TCP/IP, the majority of technical issues of interconnecting various computer technologies have become transparent to the user. Th...

  12. Campus Access Control System RFID Based

    Directory of Open Access Journals (Sweden)

    Mr. SANTHOSH S

    2012-06-01

    Full Text Available Radio frequency identification (RFID technology has helped many organizations to reduce cost. Nevertheless, there are challenges and issues associated with RFID adoption. The most common internal challenge for many organizations is justifying the investment and modification of processes. The focus of this project is to show the business value of RFID technology and its applications. The important issue is the security level of the whole campus because it needs to be carefully differentiated. Dormitories and special research laboratories should benefit from higher levels of security than any other campuses. The key to the problem is represented by the new Radio Frequency Identification (RFID which can support contactless cards with memory. The most important feature of the proposed system is the updating of access permission level at any time for the user based on the availability of that user. The data transfer from the reader to the database was done using wireless communication (RF communication. To achieve this here RF transmitter and the RF receiver is used. The data which is read by the reader is sent to the microcontroller. Then from the controller we can transfer the data to the database by using the UART module (serial communication which is inbuilt in the microcontroller through RF transmitter. RF receiver of the same frequency at the receiver end receives and then stores the data in the database. RF transmitter and Receiver – frequency for transmitting and receiving the data depends on the user as per the requirement for the application and it is based on the range of distance. For the data encoding and decoding process HCS-101 protocol is used.

  13. Access control, security, and trust a logical approach

    CERN Document Server

    Chin, Shiu-Kai

    2010-01-01

    Access Control, Security, Trust, and Logic Deconstructing Access Control Decisions A Logical Approach to Access Control PRELIMINARIES A Language for Access ControlSets and Relations Syntax SemanticsReasoning about Access Control Logical RulesFormal Proofs and Theorems Soundness of Logical RulesBasic Concepts Reference Monitors Access Control Mechanisms: Tickets and Lists Authentication Security PoliciesConfidentiality, Integrity, and Availability Discretionary Security Policies Mandatory Security Policies Military Security Policies Commercial PoliciesDISTRIBUTED ACCESS CONTROL Digital Authenti

  14. Knowledge-Based Multiple Access Protocol in Broadband Wireless ATM Networks

    DEFF Research Database (Denmark)

    Liu, Hong; Gliese, Ulrik Bo; Dittmann, Lars

    1999-01-01

    characteristics of the traffic for allocating bandwidth effeciently to CBR, VBR and ABR/UBR connections by a compromise of assignment, contetion, reservation and polling access techniques. Simulation results show that the proposed protocol can achieve a very high channel utilization of 90 % while providing...... guaranteed QoS requirements to a variety of ATM applications....

  15. EPCM - an efficient power controlled MAC protocol for mobile ad hoc network

    Science.gov (United States)

    Seth, D. D.; Patnaik, S.; Pal, S.

    2014-10-01

    To reduce interference and to save a significant amount of energy, a control of transmission power is employed in Mobile Ad hoc Network. Many researchers have reported numerous transmission power control schemes to achieve the objective. Some of those techniques use higher transmission power for control packets (Request To Send/Clear To Send) and lesser power for Data and ACK packets. These schemes, though save some amount of energy, achieve least aggregate throughput due to poor spatial reuse and hidden terminal interference. In this paper, an efficient Power Controlled Medium Access Control (EPCM) scheme is evinced, which uses uniform interference aware and minimum transmission power for both Control and Data packet. The performance of EPCM is evaluated and compared with three reported Medium Access Control protocols which are based on transmission power control schemes and is observed that the proposed protocol achieves better throughput and minimal energy consumption while avoiding the hidden terminal problem.

  16. Access Control Based on Trail Inference

    Directory of Open Access Journals (Sweden)

    ALBARELO, P. C.

    2015-06-01

    Full Text Available Professionals are constantly seeking qualification and consequently increasing their knowledge in their area of expertise. Thus, it is interesting to develop a computer system that knows its users and their work history. Using this information, even in the case of professional role change, the system could allow the renewed authorization for activities, based on previously authorized use. This article proposes a model for user access control that is embedded in a context-aware environment. The model applies the concept of trails to manage access control, recording activities usage in contexts and applying this history as a criterion to grant new accesses. Despite the fact that previous related research works consider contexts, none of them uses the concept of trails. Hence, the main contribution of this work is the use of a new access control criterion, namely, the history of previous accesses (trails. A prototype was implemented and applied in an evaluation based on scenarios. The results demonstrate the feasibility of the proposal, allowing for access control systems to use an alternative way to support access rights.

  17. Optimizing Libraries’ Content Findability Using Simple Object Access Protocol (SOAP) With Multi-Tier Architecture

    Science.gov (United States)

    Lahinta, A.; Haris, I.; Abdillah, T.

    2017-03-01

    The aim of this paper is to describe a developed application of Simple Object Access Protocol (SOAP) as a model for improving libraries’ digital content findability on the library web. The study applies XML text-based protocol tools in the collection of data about libraries’ visibility performance in the search results of the book. Model from the integrated Web Service Document Language (WSDL) and Universal Description, Discovery and Integration (UDDI) are applied to analyse SOAP as element within the system. The results showed that the developed application of SOAP with multi-tier architecture can help people simply access the website in the library server Gorontalo Province and support access to digital collections, subscription databases, and library catalogs in each library in Regency or City in Gorontalo Province.

  18. Assessing health systems for type 1 diabetes in sub-Saharan Africa: developing a 'Rapid Assessment Protocol for Insulin Access'

    DEFF Research Database (Denmark)

    Beran, David; Yudkin, John S; de Courten, Maximilian

    2006-01-01

    In order to improve the health of people with Type 1 diabetes in developing countries, a clear analysis of the constraints to insulin access and diabetes care is needed. We developed a Rapid Assessment Protocol for Insulin Access, comprising a series of questionnaires as well as a protocol...

  19. Impacts of the Nagoya Protocol on access to plant genetic resources and benefit sharing in China

    Directory of Open Access Journals (Sweden)

    Jianyong Wu

    2013-11-01

    Full Text Available The Nagoya Protocol (NP is an international legal framework for access to genetic resources and benefit-sharing. It opened for signature on February1, 2011, and was proposed to be in force 90 days after the date when the fiftieth country or regional organization had ratified it. By October 2013, the protocol had been signed by 92 countries and ratified by 26 countries. The protocol is now expected to be in force before the twelfth meeting of the Conference of the Parties (COP to the Convention on Biological Diversity (CBD in 2014. The Nagoya Protocol will change the current situation of unordered access to and free development of genetic resources. It will provide a premise and guarantee for the principle of national sovereignty of genetic resources and implementation of equitable sharing of benefits arising from their utilization. Analyses show that although genetic resources indigenous to China have been widely utilized by other developed countries, with patents taken out on some products, utilization in China has been poor owing to a weak capacity for independent innovation and underdeveloped biotechnology. China currently lacks a policy and regulatory system for access and benefit sharing (ABS to its genetic resources. It is, therefore, a pressing matter for China to improve the implementation of the NP by strengthening national and local policies and regulations on ABS. There is also a need to increase investment to support basic research capacity and develop biological technology to fully utilize genetic resources in China

  20. Access Agent Improving The Performance Of Access Control Lists

    Directory of Open Access Journals (Sweden)

    Thelis R. S.

    2015-08-01

    Full Text Available The main focus of the proposed research is maintaining the security of a network. Extranet is a popular network among most of the organizations where network access is provided to a selected group of outliers. Limiting access to an extranet can be carried out using Access Control Lists ACLs method. However handling the workload of ACLs is an onerous task for the router. The purpose of the proposed research is to improve the performance and to solidify the security of the ACLs used in a small organization. Using a high performance computer as a dedicated device to share and handle the router workload is suggested in order to increase the performance of the router when handling ACLs. Methods of detecting and directing sensitive data is also discussed in this paper. A framework is provided to help increase the efficiency of the ACLs in an organization network using the above mentioned procedures thus helping the organizations ACLs performance to be improved to be more secure and the system to perform faster. Inbuilt methods of Windows platform or Software for open source platforms can be used to make a computer function as a router. Extended ACL features allow the determining of the type of packets flowing through the router. Combining these mechanisms allows the ACLs to be improved and perform in a more efficient manner.

  1. A Novel Adaptive MAC Protocol for Wireless Internet Access Network with Smart Antennas

    Institute of Scientific and Technical Information of China (English)

    YANGJun; LIJiandong

    2004-01-01

    Employing smart antennas in the Central access point (CAP) of wireless Internet access networks is studied. Based on the characteristics of the networks and smart antennas, a Polling-based Adaptive beamforming multiple access protocol (PB-ABFMA) is proposed. In PB-ABFMA, the CAP requests the corresponding Mobile terminal (MT) to transmit training sequence just before the data packets transmission, so the Temporal reference beamforming (TRB) can be performed by the smart antennas. The CAP schedules packet transmissions based on the polling mechanism and dynamic TDMA, and a mini-slot is used to keep connectivity when an MT is idle, therefore,the access delay is reduced. Meanwhile, a simple and effec-tive access method is proposed to guarantee rapid access of new arrival MTs to the channel. Based on the “requestreply” traffic, which is the main traffic in Internet, the theoretical analysis of channel utilization and mean turnaround delay is presented. Analysis and simulation results show that the proposed PB-ABFMA protocols effectively support the application of smart antennas and provide high channel utilization and low turn-around delay.

  2. Semi-device independent random number expansion protocol with n to 1 quantum random access codes

    CERN Document Server

    Li, Hong-Wei; Yin, Zhen-Qiang; Guo, Guang-Can; Han, Zheng-Fu

    2011-01-01

    We study random number expansion protocols based on the n to 1 quantum random access codes (QRACs). We consider them in the semi-device independent scenario where the inner workings of the devices are unknown to us but we can certify the dimensions of the systems being communicated. This approach does not require the use of the entanglement and makes the physical realization of these protocols much easier than in the standard device independent scenario. We calculate the dependence of the effectiveness of the randomness generation on $n$ and find it optimal for n=3. We provide the explanation for this fact.

  3. Cryptographically Enforced Distributed Data Access Control

    NARCIS (Netherlands)

    Ibraimi, L.

    2011-01-01

    Outsourcing data storage reduces the cost of ownership. However, once data is stored on a remote server, users lose control over their sensitive data. There are two approaches to control the access to outsourced data. The first approach assumes that the outsourcee is fully trusted. This approach is

  4. A Survey on Coverage Control Protocols in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    V.Nivedhitha

    2013-04-01

    Full Text Available Coverage control algorithms play an important role in Wireless sensor network. Effective coverage control algorithms sense its coverage area with less energy spent. These coverage control models falls under various approaches like clustering, evolutionary, mobility based approaches. This paper makes a detailed survey on coverage control protocols coming under various classifications. In addition, it also discussed several protocols working mechanism with its evaluation metrics.

  5. A secure solution on hierarchical access control

    CERN Document Server

    Wei, Chuan-Sheng; Huang, Tone-Yau; Ong, Yao Lin

    2011-01-01

    Hierarchical access control is an important and traditional problem in information security. In 2001, Wu et.al. proposed an elegant solution for hierarchical access control by the secure-filter. Jeng and Wang presented an improvement of Wu et. al.'s method by the ECC cryptosystem. However, secure-filter method is insecure in dynaminc access control. Lie, Hsu and Tripathy, Paul pointed out some secure leaks on the secure-filter and presented some improvements to eliminate these secure flaws. In this paper, we revise the secure-filter in Jeng-Wang method and propose another secure solutions in hierarchical access control problem. CA is a super security class (user) in our proposed method and the secure-filter of $u_i$ in our solutions is a polynomial of degree $n_i+1$ in $\\mathbb{Z}_p^*$, $f_i(x)=(x-h_i)(x-a_1)...(x-a_{n_i})+L_{l_i}(K_i)$. Although the degree of our secure-filter is larger than others solutions, our solution is secure and efficient in dynamics access control.

  6. The linked medical data access control framework.

    Science.gov (United States)

    Kamateri, Eleni; Kalampokis, Evangelos; Tambouris, Efthimios; Tarabanis, Konstantinos

    2014-08-01

    The integration of medical data coming from multiple sources is important in clinical research. Amongst others, it enables the discovery of appropriate subjects in patient-oriented research and the identification of innovative results in epidemiological studies. At the same time, the integration of medical data faces significant ethical and legal challenges that impose access constraints. Some of these issues can be addressed by making available aggregated instead of raw record-level data. In many cases however, there is still a need for controlling access even to the resulting aggregated data, e.g., due to data provider's policies. In this paper we present the Linked Medical Data Access Control (LiMDAC) framework that capitalizes on Linked Data technologies to enable controlling access to medical data across distributed sources with diverse access constraints. The LiMDAC framework consists of three Linked Data models, namely the LiMDAC metadata model, the LiMDAC user profile model, and the LiMDAC access policy model. It also includes an architecture that exploits these models. Based on the framework, a proof-of-concept platform is developed and its performance and functionality are evaluated by employing two usage scenarios.

  7. Access Control Design and Implementations in the ATLAS Experiment

    CERN Document Server

    Leahu, M C; Avolio, G

    2008-01-01

    The ATLAS experiment operates with a significant number of hardware and software resources. Their protection against misuse is an essential task to ensure a safe and optimal operation. To achieve this goal, the Role Based Access Control (RBAC) model has been chosen for its scalability, flexibility, ease of administration and usability from the lowest operating system level to the highest software application level. This paper presents the overall design of RBAC implementation in the ATLAS experiment and the enforcement solutions in different areas such as the system administration, control room desktops and the data acquisition software. The users and the roles are centrally managed using a directory service based on Lightweight Directory Access Protocol which is kept in synchronization with the human resources and IT datab

  8. Supporting Tablet Configuration, Tracking, and Infection Control Practices in Digital Health Interventions: Study Protocol

    Science.gov (United States)

    Furberg, Robert D; Zulkiewicz, Brittany A; Hudson, Jordan P; Taylor, Olivia M; Lewis, Megan A

    2016-01-01

    Background Tablet-based health care interventions have the potential to encourage patient care in a timelier manner, allow physicians convenient access to patient records, and provide an improved method for patient education. However, along with the continued adoption of tablet technologies, there is a concomitant need to develop protocols focusing on the configuration, management, and maintenance of these devices within the health care setting to support the conduct of clinical research. Objective Develop three protocols to support tablet configuration, tablet management, and tablet maintenance. Methods The Configurator software, Tile technology, and current infection control recommendations were employed to develop three distinct protocols for tablet-based digital health interventions. Configurator is a mobile device management software specifically for iPhone operating system (iOS) devices. The capabilities and current applications of Configurator were reviewed and used to develop the protocol to support device configuration. Tile is a tracking tag associated with a free mobile app available for iOS and Android devices. The features associated with Tile were evaluated and used to develop the Tile protocol to support tablet management. Furthermore, current recommendations on preventing health care–related infections were reviewed to develop the infection control protocol to support tablet maintenance. Results This article provides three protocols: the Configurator protocol, the Tile protocol, and the infection control protocol. Conclusions These protocols can help to ensure consistent implementation of tablet-based interventions, enhance fidelity when employing tablets for research purposes, and serve as a guide for tablet deployments within clinical settings. PMID:27350013

  9. Access control mechanisms for distributed healthcare environments.

    Science.gov (United States)

    Sergl-Pommerening, Marita

    2004-01-01

    Today's IT-infrastructure provides more and more possibilities to share electronic patient data across several healthcare organizations and hospital departments. A strong requirement is sufficient data protection and security measures complying with the medical confidentiality and the data protection laws of each state or country like the European directive on data protection or the U.S. HIPAA privacy rule. In essence, the access control mechanisms and authorization structures of information systems must be able to realize the Need-To-Access principle. This principle can be understood as a set of context-sensitive access rules, regarding the patient's path across the organizations. The access control mechanisms of today's health information systems do not sufficiently satisfy this requirement, because information about participation of persons or organizations is not available within each system in a distributed environment. This problem could be solved by appropriate security services. The CORBA healthcare domain standard contains such a service for obtaining authorization decisions and administrating access decision policies (RAD). At the university hospital of Mainz we have developed an access control system (MACS), which includes the main functionality of the RAD specification and the access control logic that is needed for such a service. The basic design principles of our approach are role-based authorization, user rights with static and dynamic authorization data, context rules and the separation of three cooperating servers that provide up-to-date knowledge about users, roles and responsibilities. This paper introduces the design principles and the system design and critically evaluates the concepts based on practical experience.

  10. Subgroup analyses in randomised controlled trials: cohort study on trial protocols and journal publications.

    Science.gov (United States)

    Kasenda, Benjamin; Schandelmaier, Stefan; Sun, Xin; von Elm, Erik; You, John; Blümle, Anette; Tomonaga, Yuki; Saccilotto, Ramon; Amstutz, Alain; Bengough, Theresa; Meerpohl, Joerg J; Stegert, Mihaela; Olu, Kelechi K; Tikkinen, Kari A O; Neumann, Ignacio; Carrasco-Labra, Alonso; Faulhaber, Markus; Mulla, Sohail M; Mertz, Dominik; Akl, Elie A; Bassler, Dirk; Busse, Jason W; Ferreira-González, Ignacio; Lamontagne, Francois; Nordmann, Alain; Gloy, Viktoria; Raatz, Heike; Moja, Lorenzo; Rosenthal, Rachel; Ebrahim, Shanil; Vandvik, Per O; Johnston, Bradley C; Walter, Martin A; Burnand, Bernard; Schwenkglenks, Matthias; Hemkens, Lars G; Bucher, Heiner C; Guyatt, Gordon H; Briel, Matthias

    2014-07-16

    To investigate the planning of subgroup analyses in protocols of randomised controlled trials and the agreement with corresponding full journal publications. Cohort of protocols of randomised controlled trial and subsequent full journal publications. Six research ethics committees in Switzerland, Germany, and Canada. 894 protocols of randomised controlled trial involving patients approved by participating research ethics committees between 2000 and 2003 and 515 subsequent full journal publications. Of 894 protocols of randomised controlled trials, 252 (28.2%) included one or more planned subgroup analyses. Of those, 17 (6.7%) provided a clear hypothesis for at least one subgroup analysis, 10 (4.0%) anticipated the direction of a subgroup effect, and 87 (34.5%) planned a statistical test for interaction. Industry sponsored trials more often planned subgroup analyses compared with investigator sponsored trials (195/551 (35.4%) v 57/343 (16.6%), P<0.001). Of 515 identified journal publications, 246 (47.8%) reported at least one subgroup analysis. In 81 (32.9%) of the 246 publications reporting subgroup analyses, authors stated that subgroup analyses were prespecified, but this was not supported by 28 (34.6%) corresponding protocols. In 86 publications, authors claimed a subgroup effect, but only 36 (41.9%) corresponding protocols reported a planned subgroup analysis. Subgroup analyses are insufficiently described in the protocols of randomised controlled trials submitted to research ethics committees, and investigators rarely specify the anticipated direction of subgroup effects. More than one third of statements in publications of randomised controlled trials about subgroup prespecification had no documentation in the corresponding protocols. Definitive judgments regarding credibility of claimed subgroup effects are not possible without access to protocols and analysis plans of randomised controlled trials. © The DISCO study group 2014.

  11. Near-Optimal Deviation-Proof Medium Access Control Designs in Wireless Networks

    CERN Document Server

    Phan, Khoa Tran; van der Schaar, Mihaela

    2010-01-01

    Distributed medium access control (MAC) protocols are essential for the proliferation of low cost, decentralized wireless local area networks (WLANs). Most MAC protocols are designed with the presumption that nodes comply with prescribed rules. However, selfish nodes have natural motives to manipulate protocols in order to improve their own performance. This often degrades the performance of other nodes as well as that of the overall system. In this work, we propose a class of protocols that limit the performance gain which nodes can obtain through selfish manipulation while incurring only a small efficiency loss. The proposed protocols are based on the idea of a review strategy, with which nodes collect signals about the actions of other nodes over a period of time, use a statistical test to infer whether or not other nodes are following the prescribed protocol, and trigger a punishment if a departure from the protocol is perceived. We consider the cases of private and public signals and provide analytical a...

  12. Fairness of channel access for non-time-critical traffic using the FDDI token ring protocol

    Science.gov (United States)

    Johnson, M. J.

    1986-01-01

    The Fiber Distributed Data Interface (FDDI) is an ANSI draft proposed standard for a 100 megabit per second fiber optic token ring. FDDI supports two types of traffic, synchronous and asynchronous. Synchronous traffic is time critical traffic; stations are assigned guaranteed bandwidth to support their synchronous needs. Asynchronous traffic is lower priority and is sent only if time permits. It is proved analytically that the FDDI access protocol provides all stations on the ring with equal access to the channel to transmit asynchronous frames, regardless of the relative sizes of synchronous bandwidth allocations for individual stations. Analytic results are supported with data from simulation runs.

  13. Access Control in Data Management Systems

    CERN Document Server

    Ferrari, Elena

    2010-01-01

    Access control is one of the fundamental services that any Data Management System should provide. Its main goal is to protect data from unauthorized read and write operations. This is particularly crucial in today's open and interconnected world, where each kind of information can be easily made available to a huge user population, and where a damage or misuse of data may have unpredictable consequences that go beyond the boundaries where data reside or have been generated. This book provides an overview of the various developments in access control for data management systems. Discretionary,

  14. Access control mechanism of wireless gateway based on open flow

    Science.gov (United States)

    Peng, Rong; Ding, Lei

    2017-08-01

    In order to realize the access control of wireless gateway and improve the access control of wireless gateway devices, an access control mechanism of SDN architecture which is based on Open vSwitch is proposed. The mechanism utilizes the features of the controller--centralized control and programmable. Controller send access control flow table based on the business logic. Open vSwitch helps achieve a specific access control strategy based on the flow table.

  15. Paving the Way to Novel Phosphorus-Based Architectures: A Noncatalyzed Protocol to Access Six-Membered Heterocycles.

    Science.gov (United States)

    Romero-Nieto, Carlos; López-Andarias, Alicia; Egler-Lucas, Carolina; Gebert, Florian; Neus, Jens-Peter; Pilgram, Oliver

    2015-12-21

    Phosphorus-based heterocycles provide access to materials with properties that are inaccessible from all-carbon architectures. The unique hybridization of phosphorus gives rise to electron-accepting capacities, a large variety of coordination reactions, and the possibility of controlling the electronic properties through phosphorus postfunctionalization. Herein, we describe a new noncatalyzed synthetic protocol to prepare fused six-membered phosphorus heterocycles. In particular, we report the synthesis of novel phosphaphenalenes. These fused systems exhibit the benefits of both five- and six-membered phosphorus heterocycles and enable a series of versatile postfunctionalization reactions. This work thus opens up new horizons in the field of conjugated materials.

  16. A hybrid medium access control for convergence of broadband wireless and wireline ATM networks

    DEFF Research Database (Denmark)

    Liu, Hong; Gliese, Ulrik Bo; Dittmann, Lars

    2000-01-01

    of contention, reservation and polling access techniques based on the dynamic TDMA system. Extensive simulation results using realistic data traffic sources, show that the proposed medium access scheme may provide QoS guarantees to different ATM traffic including the realistic MPEG video traces with low cell......In this paper, we propose a hybrid medium access control protocol for supporting broadband integrated services in the wireless ATM networks. The integrated services include CBR, VBR and ABR traffic varying from low bit-rate to very high bit-rate. The proposed protocol is an excellent compromise...

  17. Control protocol: large scale implementation at the CERN PS complex - a first assessment

    Energy Technology Data Exchange (ETDEWEB)

    Abie, H. (CERN, 1211, Geneva 23 (Switzerland)); Benincasa, G. (CERN, 1211, Geneva 23 (Switzerland)); Coudert, G. (CERN, 1211, Geneva 23 (Switzerland)); Davydenko, Y. (CERN, 1211, Geneva 23 (Switzerland)); Dehavay, C. (CERN, 1211, Geneva 23 (Switzerland)); Gavaggio, R. (CERN, 1211, Geneva 23 (Switzerland)); Gelato, G. (CERN, 1211, Geneva 23 (Switzerland)); Heinze, W. (CERN, 1211, Geneva 23 (Switzerland)); Legras, M. (CERN, 1211, Geneva 23 (Switzerland)); Lustig, H. (CERN, 1211, Geneva 23 (Switzerland)); Merard, L. (CERN, 1211, Geneva 23 (Switzerland)); Pearson, T. (CERN, 1211, Geneva 23 (Switzerland)); Strubin, P. (CERN, 1211, Geneva 23 (Switzerland)); Tedesco, J. (CERN, 1211, Geneva 23 (Switzerland))

    1994-12-15

    The Control Protocol is a model-based, uniform access procedure from a control system to accelerator equipment. It was proposed at CERN about 5 years ago and prototypes were developed in the following years. More recently, this procedure has been finalized and implemented at a large scale in the PS Complex. More than 300 pieces of equipment are now using this protocol in normal operation and another 300 are under implementation. These include power converters, vacuum systems, beam instrumentation devices, RF equipment, etc. This paper describes how the single general procedure is applied to the different kinds of equipment. The advantages obtained are also discussed. ((orig.))

  18. Control protocol: large scale implementation at the CERN PS complex — a first assessment

    Science.gov (United States)

    Abie, H.; Benincasa, G.; Coudert, G.; Davydenko, Y.; Dehavay, C.; Gavaggio, R.; Gelato, G.; Heinze, W.; Legras, M.; Lustig, H.; Merard, L.; Pearson, T.; Strubin, P.; Tedesco, J.

    1994-12-01

    The Control Protocol is a model-based, uniform access procedure from a control system to accelerator equipment. It was proposed at CERN about 5 years ago and prototypes were developed in the following years. More recently, this procedure has been finalized and implemented at a large scale in the PS Complex. More than 300 pieces of equipment are now using this protocol in normal operation and another 300 are under implementation. These include power converters, vacuum systems, beam instrumentation devices, RF equipment, etc. This paper describes how the single general procedure is applied to the different kinds of equipment. The advantages obtained are also discussed.

  19. Control of optics in random access analysers

    OpenAIRE

    Truchaud, A.

    1988-01-01

    The technology behind random access analysers involves flexible optical systems which can measure absorbances for one reaction at different scheduled times, and for several reactions performed simultaneously at different wavelengths. Optics control involves light sources (continuous and flash mode), indexing of monochromatic filters, injection-moulded plastic cuvettes, optical fibres, and polychromatic analysis.

  20. Role-based access control in retrospect

    NARCIS (Netherlands)

    Franqueira, Virginia N.L.; Wieringa, Roel

    2012-01-01

    Role-Based Access Control (RBAC) has been a success in terms of the amount of research that went into it, its uptake in international standards, and its adoption by major software vendors. Yet, RBAC remains complex to implement in user organizations. In this paper we review the state of the art of R

  1. Atom-Role-Based Access Control Model

    Science.gov (United States)

    Cai, Weihong; Huang, Richeng; Hou, Xiaoli; Wei, Gang; Xiao, Shui; Chen, Yindong

    Role-based access control (RBAC) model has been widely recognized as an efficient access control model and becomes a hot research topic of information security at present. However, in the large-scale enterprise application environments, the traditional RBAC model based on the role hierarchy has the following deficiencies: Firstly, it is unable to reflect the role relationships in complicated cases effectively, which does not accord with practical applications. Secondly, the senior role unconditionally inherits all permissions of the junior role, thus if a user is under the supervisor role, he may accumulate all permissions, and this easily causes the abuse of permission and violates the least privilege principle, which is one of the main security principles. To deal with these problems, we, after analyzing permission types and role relationships, proposed the concept of atom role and built an atom-role-based access control model, called ATRBAC, by dividing the permission set of each regular role based on inheritance path relationships. Through the application-specific analysis, this model can well meet the access control requirements.

  2. An electronically controlled automatic security access gate

    Directory of Open Access Journals (Sweden)

    Jonathan A. ENOKELA

    2014-11-01

    Full Text Available The security challenges being encountered in many places require electronic means of controlling access to communities, recreational centres, offices, and homes. The electronically controlled automated security access gate being proposed in this work helps to prevent an unwanted access to controlled environments. This is achieved mainly through the use of a Radio Frequency (RF transmitter-receiver pair. In the design a microcontroller is programmed to decode a given sequence of keys that is entered on a keypad and commands a transmitter module to send out this code as signal at a given radio frequency. Upon reception of this RF signal by the receiver module, another microcontroller activates a driver circuitry to operate the gate automatically. The codes for the microcontrollers were written in C language and were debugged and compiled using the KEIL Micro vision 4 integrated development environment. The resultant Hex files were programmed into the memories of the microcontrollers with the aid of a universal programmer. Software simulation was carried out using the Proteus Virtual System Modeling (VSM version 7.7. A scaled-down prototype of the system was built and tested. The electronically controlled automated security access gate can be useful in providing security for homes, organizations, and automobile terminals. The four-character password required to operate the gate gives the system an increased level of security. Due to its standalone nature of operation the system is cheaper to maintain in comparison with a manually operated type.

  3. Access Control from an Intrusion Detection Perspective

    NARCIS (Netherlands)

    Nunes Leal Franqueira, V.

    Access control and intrusion detection are essential components for securing an organization's information assets. In practice, these components are used in isolation, while their fusion would contribute to increase the range and accuracy of both. One approach to accomplish this fusion is the

  4. Power-Controlled MAC Protocols with Dynamic Neighbor Prediction for Ad hoc Networks

    Institute of Scientific and Technical Information of China (English)

    LI Meng; ZHANG Lin; XIAO Yong-kang; SHAN Xiu-ming

    2004-01-01

    Energy and bandwidth are the scarce resources in ad hoc networks because most of the mobile nodes are battery-supplied and share the exclusive wireless medium. Integrating the power control into MAC protocol is a promising technique to fully exploit these precious resources of ad hoc wireless networks. In this paper, a new intelligent power-controlled Medium Access Control (MAC) (iMAC) protocol with dynamic neighbor prediction is proposed. Through the elaborate design of the distributed transmit-receive strategy of mobile nodes, iMAC greatly outperforms the prevailing IEEE 802.11 MAC protocols in not only energy conservation but also network throughput. Using the Dynamic Neighbor Prediction (DNP), iMAC performs well in mobile scenes. To the best of our knowledge, iMAC is the first protocol that considers the performance deterioration of power-controlled MAC protocols in mobile scenes and then proposes a solution. Simulation results indicate that DNP is important and necessary for power-controlled MAC protocols in mobile ad hoc networks.

  5. On the Need of Novel Medium Access Control Schemes for Network Coding enabled Wireless Mesh Networks

    DEFF Research Database (Denmark)

    Paramanathan, Achuthan; Pahlevani, Peyman; Roetter, Daniel Enrique Lucani;

    2013-01-01

    This paper advocates for a new Medium Access Control (MAC) strategy for wireless meshed networks by identifying overload scenarios in order to provide additional channel access priority to the relay. The key behind our MAC protocol is that the relay will adjust its back off window size according...... to the incoming and outgoing packet ratio. We describe the new protocol as an extension to the CSMA/CA protocol and implement the protocol on our own hardware platform. By means of our own testbed, we investigate two basic network structures, namely, the two-way relay and the cross topology. It is well known...... that network coding will improve the throughput in such systems, but our novel medium access scheme improves the performance in the cross topology by another 66 % for network coding and 150 % for classical forwarding in theory. These gains translate in a theoretical gain of 33 % of network coding over...

  6. Traffic Adaptive Energy Efficient and Low Latency Medium Access Control for Wireless Sensor Networks

    Science.gov (United States)

    Yadav, Rajesh; Varma, Shirshu; Malaviya, N.

    2008-05-01

    Medium access control for wireless sensor networks has been a very active research area in the recent years. The traditional wireless medium access control protocol such as IEEE 802.11 is not suitable for the sensor network application because these are battery powered. The recharging of these sensor nodes is expensive and also not possible. The most of the literature in the medium access for the sensor network focuses on the energy efficiency. The proposed MAC protocol solves the energy inefficiency caused by idle listening, control packet overhead and overhearing taking nodes latency into consideration based on the network traffic. Simulation experiments have been performed to demonstrate the effectiveness of the proposed approach. The validation of the simulation results of the proposed MAC has been done by comparing it with the analytical model. This protocol has been simulated in Network Simulator ns-2.

  7. VHDL IMPLEMENTATION OF TEST ACCESS PORT CONTROLLER

    Directory of Open Access Journals (Sweden)

    MANPREET KAUR

    2012-06-01

    Full Text Available In this paper, an implementation of IEEE 1149.7 standard is used for designing Test Access Port (TAP Controller and testing of interconnects is done using boundary scan. By c-JTAG the pin count gets reduced which increases the performance and simplifies the connection between devices. TAP Controller is a synchronous Moore type finite state machine that is changed when the TMS and TCK signals of the test access port gets change. This controls the sequence operation of the circuitry conveyed by JTAG and c-JTAG. JTAGmainly used four pins with TAP and fifth pin is for optional use in Boundary scan. But c-JTAG uses only two pins with TAP. In this approach TDI and TDO gets multiplexed by using class T4 and T5 of c-JTAG. Various instructions are used for testing interconnects using IEEE 1149.7 standard (std.

  8. Design of Intelligent Cross-Layer Routing Protocols for Airborne Wireless Networks Under Dynamic Spectrum Access Paradigm

    Science.gov (United States)

    2011-05-01

    routing protocols require link layer detection and hello message to maintain multiple routes . Various single and multipath protocols , like AODV ... protocols (e.g., AODV , DSR, Optimized Link State Routing (OLSR) etc.) with and without link layer detection. The protocols with link layer detection...Reactive protocols like AODV tend to reduce the control traffic messages overhead at the cost of increased latency in finding new routes . AODV has a

  9. Intelligent Security Auditing Based on Access Control of Devices in Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    XU Guang-wei; SHI You-qun; ZHU Ming; WU Guo-wen; CAO Qi-ying

    2006-01-01

    Security in Ad Hoc network is an important issue under the opening circumstance of application service. Some protocols and models of security auditing have been proposed to ensure rationality of contracting strategy and operating regulation and used to identify abnormal operation. Model of security auditing based on access control of devices will be advanced to register sign of devices and property of event of access control and to audit those actions. In the end, the model is analyzed and simulated.

  10. A Novel Multiple Access Protocol for Mobile Ad Hoc Network with Smart Antennas

    Institute of Scientific and Technical Information of China (English)

    YANGJun; LIJiandong; ZHOUXiaodong

    2004-01-01

    The approach to employ smart antennas in Mobile ad hoc network (MANET) nodes is presented. An adaptive beamforming-Carrier-Sense multiple access/collison avoidance) (ABF-CSMA/CA) protocol is proposed. In the ABF-CSMA/CA, Request-to-Send/Clear-to-Send (RTS/CTS) dialogue is used to distribute channel reservation information. Training sequences are transmitted just before RTS and CTS packets, so the Temporal reference beamforming (TRB) can be performed by the source node and the destination node.An improved virtual carrier-sense mechanism is also proposed to enhance Collision avoidance (CA) and obtain efficient Space division multiple access (SDMA). In this scheme, every node has two kinds of Network allocation vector (NAV): an oNAV maintains the interval of ongoing transmission of neighbors whose smart antennas operate in omnidirectional mode, and multiple bNAVs maintain those intervals of neighbors whose smart antennas operate in beamforming mode. Theoretical analysis of channel utilization of the proposed protocol is presented. Results show that ABF-CSMA/CA protocol combining with smart antennas can provide higher channel utilization.

  11. Speed control system for an access gate

    Science.gov (United States)

    Bzorgi, Fariborz M.

    2012-03-20

    An access control apparatus for an access gate. The access gate typically has a rotator that is configured to rotate around a rotator axis at a first variable speed in a forward direction. The access control apparatus may include a transmission that typically has an input element that is operatively connected to the rotator. The input element is generally configured to rotate at an input speed that is proportional to the first variable speed. The transmission typically also has an output element that has an output speed that is higher than the input speed. The input element and the output element may rotate around a common transmission axis. A retardation mechanism may be employed. The retardation mechanism is typically configured to rotate around a retardation mechanism axis. Generally the retardation mechanism is operatively connected to the output element of the transmission and is configured to retard motion of the access gate in the forward direction when the first variable speed is above a control-limit speed. In many embodiments the transmission axis and the retardation mechanism axis are substantially co-axial. Some embodiments include a freewheel/catch mechanism that has an input connection that is operatively connected to the rotator. The input connection may be configured to engage an output connection when the rotator is rotated at the first variable speed in a forward direction and configured for substantially unrestricted rotation when the rotator is rotated in a reverse direction opposite the forward direction. The input element of the transmission is typically operatively connected to the output connection of the freewheel/catch mechanism.

  12. The U.S. Culture Collection Network Responding to the Requirements of the Nagoya Protocol on Access and Benefit Sharing

    National Research Council Canada - National Science Library

    Kevin McCluskey; Katharine B. Barker; Hazel A. Barton; Kyria Boundy-Mills; Daniel R. Brown; Jonathan A. Coddington; Kevin Cook; Philippe Desmeth; David Geiser; Jessie A. Glaeser; Stephanie Greene; Seogchan Kang; Michael W. Lomas; Ulrich Melcher; Scott E. Miller; David R. Nobles; Kristina J. Owens; Jerome H. Reichman; Manuela da Silva; John Wertz; Cale Whitworth; David Smith; Steven E. Lindow

    2017-01-01

    The U.S. Culture Collection Network held a meeting to share information about how culture collections are responding to the requirements of the recently enacted Nagoya Protocol on Access to Genetic Resources...

  13. A Theorem on Grid Access Control

    Institute of Scientific and Technical Information of China (English)

    XU ZhiWei(徐志伟); BU GuanYing(卜冠英)

    2003-01-01

    The current grid security research is mainly focused on the authentication of grid systems. A problem to be solved by grid systems is to ensure consistent access control. This problem is complicated because the hosts in a grid computing environment usually span multiple autonomous administrative domains. This paper presents a grid access control model, based on asynchronous automata theory and the classic Bell-LaPadula model. This model is useful to formally study the confidentiality and integrity problems in a grid computing environment. A theorem is proved, which gives the necessary and sufficient conditions to a grid to maintain confidentiality.These conditions are the formalized descriptions of local (node) relations or relationship between grid subjects and node subjects.

  14. Predictive access control for distributed computation

    DEFF Research Database (Denmark)

    Yang, Fan; Hankin, Chris; Nielson, Flemming

    2013-01-01

    We show how to use aspect-oriented programming to separate security and trust issues from the logical design of mobile, distributed systems. The main challenge is how to enforce various types of security policies, in particular predictive access control policies — policies based on the future...... behavior of a program. A novel feature of our approach is that we can define policies concerning secondary use of data....

  15. An Action-Based Fine-Grained Access Control Mechanism for Structured Documents and Its Application

    Directory of Open Access Journals (Sweden)

    Mang Su

    2014-01-01

    Full Text Available This paper presents an action-based fine-grained access control mechanism for structured documents. Firstly, we define a describing model for structured documents and analyze the application scenarios. The describing model could support the permission management on chapters, pages, sections, words, and pictures of structured documents. Secondly, based on the action-based access control (ABAC model, we propose a fine-grained control protocol for structured documents by introducing temporal state and environmental state. The protocol covering different stages from document creation, to permission specification and usage control are given by using the Z-notation. Finally, we give the implementation of our mechanism and make the comparisons between the existing methods and our mechanism. The result shows that our mechanism could provide the better solution of fine-grained access control for structured documents in complicated networks. Moreover, it is more flexible and practical.

  16. Distributed medium access control in wireless networks

    CERN Document Server

    Wang, Ping

    2013-01-01

    This brief investigates distributed medium access control (MAC) with QoS provisioning for both single- and multi-hop wireless networks including wireless local area networks (WLANs), wireless ad hoc networks, and wireless mesh networks. For WLANs, an efficient MAC scheme and a call admission control algorithm are presented to provide guaranteed QoS for voice traffic and, at the same time, increase the voice capacity significantly compared with the current WLAN standard. In addition, a novel token-based scheduling scheme is proposed to provide great flexibility and facility to the network servi

  17. A Novel Medium Access Control for Ad hoc Networks Based on OFDM System

    Institute of Scientific and Technical Information of China (English)

    YU Yi-fan; YIN Chang-chuan; YUE Guang-xin

    2005-01-01

    Recently, hosts of Medium Access Control (MAC) protocols for Ad hoc radio networks have been proposed to solve the hidden terminal problem and exposed terminal problem. However most of them take into no account the interactions between physical (PHY) system and MAC protocol. Therefore, the current MAC protocols are either inefficient in the networks with mobile nodes and fading channel or difficult in hardware implementation. In this paper, we present a novel media access control for Ad hoc networks that integrates a media access control protocol termed as Dual Busy Tone Multiple Access (DBTMA) into Orthogonal Frequency Division Multiplexing (OFDM) system proposed in IEEE 802.11a standard. The analysis presented in the paper indicates that the proposed MAC scheme achieves performance improvement over IEEE 802.11 protocol about 25%~80% especially in the environment with high mobility and deep fading. The complexity of the proposed scheme is also lower than other implementation of similar busy tone solution. Furthermore, it is compatible with IEEE 802.11a networks.

  18. Emulation of Industrial Control Field Device Protocols

    Science.gov (United States)

    2013-03-01

    SCADA: Supervisory Control and Data Acquisition. International Society of Automation, 2009. [Cap10] Capula Limited. Case study: Alstom power...via the HMI, more than 99% of all messages from 5 the MTU are automatic [Boy09]. This is particularly true for very complex or very large systems where...telemetry units ( RTU ) (as opposed to remote terminal units) and programmable logic controllers (PLC). While similar in concept, there are differences

  19. Partner randomized controlled trial: study protocol and coaching intervention

    Directory of Open Access Journals (Sweden)

    Garbutt Jane M

    2012-04-01

    Full Text Available Abstract Background Many children with asthma live with frequent symptoms and activity limitations, and visits for urgent care are common. Many pediatricians do not regularly meet with families to monitor asthma control, identify concerns or problems with management, or provide self-management education. Effective interventions to improve asthma care such as small group training and care redesign have been difficult to disseminate into office practice. Methods and design This paper describes the protocol for a randomized controlled trial (RCT to evaluate a 12-month telephone-coaching program designed to support primary care management of children with persistent asthma and subsequently to improve asthma control and disease-related quality of life and reduce urgent care events for asthma care. Randomization occurred at the practice level with eligible families within a practice having access to the coaching program or to usual care. The coaching intervention was based on the transtheoretical model of behavior change. Targeted behaviors included 1 effective use of controller medications, 2 effective use of rescue medications and 3 monitoring to ensure optimal control. Trained lay coaches provided parents with education and support for asthma care, tailoring the information provided and frequency of contact to the parent's readiness to change their child's day-to-day asthma management. Coaching calls varied in frequency from weekly to monthly. For each participating family, follow-up measurements were obtained at 12- and 24-months after enrollment in the study during a telephone interview. The primary outcomes were the mean change in 1 the child's asthma control score, 2 the parent's quality of life score, and 3 the number of urgent care events assessed at 12 and 24 months. Secondary outcomes reflected adherence to guideline recommendations by the primary care pediatricians and included the proportion of children prescribed controller medications

  20. A Calculus for Control Flow Analysis of Security Protocols

    DEFF Research Database (Denmark)

    Buchholtz, Mikael; Nielson, Hanne Riis; Nielson, Flemming

    2004-01-01

    analysis methodology. We pursue an analysis methodology based on control flow analysis in flow logic style and we have previously shown its ability to analyse a variety of security protocols. This paper develops a calculus, LysaNS that allows for much greater control and clarity in the description...

  1. The prevention access and risk taking in young people (PARTY project protocol: A cluster randomised controlled trial of health risk screening and motivational interviewing for young people presenting to general practice

    Directory of Open Access Journals (Sweden)

    Sanci Lena

    2012-06-01

    Full Text Available Abstract Background There are growing worldwide concerns about the ability of primary health care systems to manage the major burden of illness in young people. Over two thirds of premature adult deaths result from risks that manifest in adolescence, including injury, neuropsychiatric problems and consequences of risky behaviours. One policy response is to better reorientate primary health services towards prevention and early intervention. Currently, however, there is insufficient evidence to support this recommendation for young people. This paper describes the design and implementation of a trial testing an intervention to promote psychosocial risk screening of all young people attending general practice and to respond to identified risks using motivational interviewing. Main outcomes: clinicians’ detection of risk-taking and emotional distress, young people’s intention to change and reduction of risk taking. Secondary outcomes: pathways to care, trust in the clinician and likelihood of returning for future visits. The design of the economic and process evaluation are not detailed in this protocol. Methods PARTY is a cluster randomised trial recruiting 42 general practices in Victoria, Australia. Baseline measures include: youth friendly practice characteristics; practice staff’s self-perceived competency in young people’s care and clinicians’ detection and response to risk taking behaviours and emotional distress in 14–24 year olds, attending the practice. Practices are then stratified by a social disadvantage index and billing methods and randomised. Intervention practices receive: nine hours of training and tools; feedback of their baseline data and two practice visits over six weeks. Comparison practices receive a three hour seminar in youth friendly practice only. Six weeks post-intervention, 30 consecutive young people are interviewed post-consultation from each practice and followed-up for self-reported risk taking

  2. The prevention access and risk taking in young people (PARTY) project protocol: a cluster randomised controlled trial of health risk screening and motivational interviewing for young people presenting to general practice.

    Science.gov (United States)

    Sanci, Lena; Grabsch, Brenda; Chondros, Patty; Shiell, Alan; Pirkis, Jane; Sawyer, Susan; Hegarty, Kelsey; Patterson, Elizabeth; Cahill, Helen; Ozer, Elizabeth; Seymour, Janelle; Patton, George

    2012-06-06

    There are growing worldwide concerns about the ability of primary health care systems to manage the major burden of illness in young people. Over two thirds of premature adult deaths result from risks that manifest in adolescence, including injury, neuropsychiatric problems and consequences of risky behaviours. One policy response is to better reorientate primary health services towards prevention and early intervention. Currently, however, there is insufficient evidence to support this recommendation for young people. This paper describes the design and implementation of a trial testing an intervention to promote psychosocial risk screening of all young people attending general practice and to respond to identified risks using motivational interviewing. clinicians' detection of risk-taking and emotional distress, young people's intention to change and reduction of risk taking. pathways to care, trust in the clinician and likelihood of returning for future visits. The design of the economic and process evaluation are not detailed in this protocol. PARTY is a cluster randomised trial recruiting 42 general practices in Victoria, Australia. Baseline measures include: youth friendly practice characteristics; practice staff's self-perceived competency in young people's care and clinicians' detection and response to risk taking behaviours and emotional distress in 14-24 year olds, attending the practice. Practices are then stratified by a social disadvantage index and billing methods and randomised. Intervention practices receive: nine hours of training and tools; feedback of their baseline data and two practice visits over six weeks. Comparison practices receive a three hour seminar in youth friendly practice only. Six weeks post-intervention, 30 consecutive young people are interviewed post-consultation from each practice and followed-up for self-reported risk taking behaviour and emotional distress three and 12 months post consultation. The PARTY trial is the

  3. Survey of Performance based Transmission Control Protocol in MANET

    Directory of Open Access Journals (Sweden)

    Sapna Bagde

    2013-01-01

    Full Text Available Transmission Control Protocol (TCP is a connection-oriented transport service that ensures the reliability of message delivery. It verifies that messages and data were received. TCP provides reliable, ordered delivery of a stream of bytes from a program on one computer to another program on another computer. TCP provides a communication service at an intermediate level between an application programs. TCP is the protocol used by major Internet applications such as the World Wide Web, email, remote administration and file transfer. TCP is a reliable transport protocol that is well tuned to perform well in traditional networks. However, several experiments and analysis have shown that this protocol is not suitable for bulk data transfer in high bandwidth, large round trip time networks because of its slow start and conservative congestion control mechanism. In this paper we discussed a survey of Performance Based Transmission Control Protocol in Mobile Ad-hoc Network environment. The performance based techniques are categorized based upon different approaches like throughput, end-to-end delay, congestion control etc. We also analysis the major improvement in recent methods for performance based TCP in MANET.

  4. Chapter 19: HVAC Controls (DDC/EMS/BAS) Evaluation Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Romberger, J.

    2014-11-01

    The HVAC Controls Evaluation Protocol is designed to address evaluation issues for direct digital controls/energy management systems/building automation systems (DDC/EMS/BAS) that are installed to control heating, ventilation, and air-conditioning (HVAC) equipment in commercial and institutional buildings. (This chapter refers to the DDC/EMS/BAS measure as HVAC controls.) This protocol may also be applicable to industrial facilities such as clean rooms and labs, which have either significant HVAC equipment or spaces requiring special environmental conditions. This protocol addresses only HVAC-related equipment and the energy savings estimation methods associated with installing such control systems as an energy efficiency measure. The affected equipment includes: Air-side equipment (air handlers, direct expansion systems, furnaces, other heating- and cooling-related devices, terminal air distribution equipment, and fans); Central plant equipment (chillers, cooling towers, boilers, and pumps). These controls may also operate or affect other end uses, such as lighting, domestic hot water, irrigation systems, and life safety systems such as fire alarms and other security systems. Considerable nonenergy benefits, such as maintenance scheduling, system component troubleshooting, equipment failure alarms, and increased equipment lifetime, may also be associated with these systems. When connected to building utility meters, these systems can also be valuable demand-limiting control tools. However, this protocol does not evaluate any of these additional capabilities and benefits.

  5. A service-oriented data access control model

    Science.gov (United States)

    Meng, Wei; Li, Fengmin; Pan, Juchen; Song, Song; Bian, Jiali

    2017-01-01

    The development of mobile computing, cloud computing and distributed computing meets the growing individual service needs. Facing with complex application system, it's an urgent problem to ensure real-time, dynamic, and fine-grained data access control. By analyzing common data access control models, on the basis of mandatory access control model, the paper proposes a service-oriented access control model. By regarding system services as subject and data of databases as object, the model defines access levels and access identification of subject and object, and ensures system services securely to access databases.

  6. Shared access protocol (SAP) in femtocell channel resources for cellular coverage enhancement

    KAUST Repository

    Magableh, Amer M.

    2012-12-01

    Femtocells are promising techniques employed in cellular systems to enhance the indoor coverage, especially in areas with high density and high traffic rates. In this paper, we propose an efficient resource utilization protocol, named shared access protocol (SAP), that enables the unlicensed macro-cell user equipments (MC-UE) to communicate with partially closed access femtocell base stations and hence, improves and enhances the overall system performance in closed environments. For the proposed system model, we obtain, in closed-form, the main signal-to-interference plus noise ratio (SINR) characteristics, including the probability density function (PDF) and the cumulative distribution function (CDF). In addition, these expressions are further used to derive several performance metrics in closed-form, such as, the average bit error rate (BER), outage probability, and the average channel capacity for the proposed SAP herein. Furthermore, Monte-carlo simulations as well as numerical results are provided showing a good match that ensures and confirms the correctness of the derived expressions. © 2012 IEEE.

  7. FLOSYS--a web-accessible workflow system for protocol-driven biomolecular sequence analysis.

    Science.gov (United States)

    Badidi, E; Lang, B F; Burger, G

    2004-11-01

    FLOSYS is an interactive web-accessible bioinformatics workflow system designed to assist biologists in multi-step data analyses. FLOSYS allows the user to create complex analysis pathways (protocols) graphically, similar to drawing a flowchart: icons representing particular bioinformatics tools are dragged and dropped onto a canvas and lines connecting those icons are drawn to specify the relationships between the tools. In addition, FLOSYS permits to select input-data, execute the protocol and store the results in a personal workspace. The three-tier architecture of FLOSYS has been implemented in Java and uses a relational database system together with new technologies for distributed and web computing such as CORBA, RMI, JSP and JDBC. The prototype of FLOSYS, which is part of the bioinformatics workbench AnaBench, is accessible on-line at http://malawimonas.bcm.umontreal.ca: 8091/anabench. The entire package is available on request to academic groups who wish to have a customized local analysis environment for research or teaching.

  8. A web product data management system based on Simple Object Access Protocol

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new web product data management architecture is presented. The three-tier web architecture and Simple Object Access Protocol (SOAP) are combined to build the web-based product data management (PDM) system which includes three tiers: the user services tier, the business services tier, and the data services tier. The client service component uses the serverside technology, and Extensible Markup Language (XML) web service which uses SOAP as the communication protocol is chosen as the business service component. To illustrate how to build a web-based PDM system using the proposed architecture,a case PDM system which included three logical tires was built. To use the security and central management features of the database, a stored procedure was recommended in the data services tier. The business object was implemented as an XML web service so that client could use standard internet protocols to communicate with the business object from any platform. In order to satisfy users using all sorts of browser, the server-side technology and Microsoft ASP.NET was used to create the dynamic user interface.

  9. Perti Net-Based Workflow Access Control Model

    Institute of Scientific and Technical Information of China (English)

    陈卓; 骆婷; 石磊; 洪帆

    2004-01-01

    Access control is an important protection mechanism for information systems. This paper shows how to make access control in workflow system. We give a workflow access control model (WACM) based on several current access control models. The model supports roles assignment and dynamic authorization. The paper defines the workflow using Petri net. It firstly gives the definition and description of the workflow, and then analyzes the architecture of the workflow access control model (WACM). Finally, an example of an e-commerce workflow access control model is discussed in detail.

  10. A citywide prehospital protocol increases access to stroke thrombolysis in Toronto.

    Science.gov (United States)

    Gladstone, David J; Rodan, Lance H; Sahlas, Demetrios J; Lee, Liesly; Murray, Brian J; Ween, Jon E; Perry, James R; Chenkin, Jordan; Morrison, Laurie J; Beck, Shann; Black, Sandra E

    2009-12-01

    Intravenous tissue plasminogen activator for ischemic stroke is approved for eligible patients who can be treated within a 3-hour window, but treatment rates remain disappointingly low, often protocol was implemented by the provincial government to transport acute stroke patients directly to one of 3 regional stroke centers, bypassing local hospitals. This comprised a paramedic screening tool, ambulance destination decision rule, and formal memorandum of understanding of system stakeholders. This report describes the initial impact of the activation protocol at our regional stroke center. We compared consecutive patients with stroke arriving to our stroke center during the first 4 months of this new triage protocol (February 14 to June 14, 2005) versus the same 4-month period in 2004. The protocol resulted in an immediate doubling in the number of patients with acute stroke arriving to our regional stroke center within 2.5 hours of symptom onset. We observed a 4-fold increase in patients who were eligible for and treated with tissue plasminogen activator. The tissue plasminogen activator treatment rate for ischemic stroke patients increased from 9.5% to 23.4% (P=0.01), and one in 2 patients with ischemic stroke arriving within 2.5 hours received thrombolysis during this period (one in 5 of patients with ischemic stroke overall). The median onset-to-needle time for tissue plasminogen activator-treated patients was significantly reduced. Many implementation challenges were identified and addressed. This prehospital triage was immediately successful in improving tissue plasminogen activator access for patients with ischemic stroke, enabling our center to achieve one of the highest tissue plasminogen activator treatment rates in North America and underscoring the need for coordinated systems of acute stroke care. Sustainability of such an initiative will be dependent on interdisciplinary teamwork, ongoing paramedic training, adequate hospital staffing, bed availability

  11. Adaptive Media Access Control for Energy Harvesting - Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon; Dragoni, Nicola

    2012-01-01

    ODMAC (On-Demand Media Access Control) is a recently proposed MAC protocol designed to support individual duty cycles for Energy Harvesting — Wireless Sensor Networks (EH-WSNs). Individual duty cycles are vital for EH-WSNs, because they allow nodes to adapt their energy consumption to the ever......-changing environmental energy sources. In this paper, we present an improved and extended version of ODMAC and we analyze it by means of an analytical model that can approximate several performance metrics in an arbitrary network topology. The simulations and the analytical experiments show ODMAC's ability to satisfy...... three key properties of EH-WSNs: adaptability of energy consumption, distributed energy-aware load balancing and support for different application-specific requirements....

  12. A noise immunity controlled quantum teleportation protocol

    Science.gov (United States)

    Li, Dong-fen; Wang, Rui-jin; Zhang, Feng-li; Baagyere, Edward; Qin, Zhen; Xiong, Hu; Zhan, Huayi

    2016-08-01

    With the advent of the Internet and information and communication technology, quantum teleportation has become an important field in information security and its application areas. This is because quantum teleportation has the ability to attain a timely secret information delivery and offers unconditional security. And as such, the field of quantum teleportation has become a hot research topic in recent years. However, noise has serious effect on the safety of quantum teleportation within the aspects of information fidelity, channel capacity and information transfer. Therefore, the main purpose of this paper is to address these problems of quantum teleportation. Firstly, in order to resist collective noise, we construct a decoherence-free subspace under different noise scenarios to establish a two-dimensional fidelity quantum teleportation models. And also create quantum teleportation of multiple degree of freedom, and these models ensure the accuracy and availability of the exchange of information and in multiple degree of freedom. Secondly, for easy preparation, measurement and implementation, we use super dense coding features to build an entangled quantum secret exchange channel. To improve the channel utilization and capacity, an efficient super dense coding method based on ultra-entanglement exchange is used. Thirdly, continuous variables of the controlled quantum key distribution were designed for quantum teleportation; in addition, we perform Bell-basis measurement under the collective noise and also prepare the storage technology of quantum states to achieve one-bit key by three-photon encoding to improve its security and efficiency. We use these two methods because they conceal information, resist a third party attack and can detect eavesdropping. Our proposed methods, according to the security analysis, are able to solve the problems associated with the quantum teleportation under various noise environments.

  13. A noise immunity controlled quantum teleportation protocol

    Science.gov (United States)

    Li, Dong-fen; Wang, Rui-jin; Zhang, Feng-li; Baagyere, Edward; Qin, Zhen; Xiong, Hu; Zhan, Huayi

    2016-11-01

    With the advent of the Internet and information and communication technology, quantum teleportation has become an important field in information security and its application areas. This is because quantum teleportation has the ability to attain a timely secret information delivery and offers unconditional security. And as such, the field of quantum teleportation has become a hot research topic in recent years. However, noise has serious effect on the safety of quantum teleportation within the aspects of information fidelity, channel capacity and information transfer. Therefore, the main purpose of this paper is to address these problems of quantum teleportation. Firstly, in order to resist collective noise, we construct a decoherence-free subspace under different noise scenarios to establish a two-dimensional fidelity quantum teleportation models. And also create quantum teleportation of multiple degree of freedom, and these models ensure the accuracy and availability of the exchange of information and in multiple degree of freedom. Secondly, for easy preparation, measurement and implementation, we use super dense coding features to build an entangled quantum secret exchange channel. To improve the channel utilization and capacity, an efficient super dense coding method based on ultra-entanglement exchange is used. Thirdly, continuous variables of the controlled quantum key distribution were designed for quantum teleportation; in addition, we perform Bell-basis measurement under the collective noise and also prepare the storage technology of quantum states to achieve one-bit key by three-photon encoding to improve its security and efficiency. We use these two methods because they conceal information, resist a third party attack and can detect eavesdropping. Our proposed methods, according to the security analysis, are able to solve the problems associated with the quantum teleportation under various noise environments.

  14. Research of user access control for networked manufacturing system

    Institute of Scientific and Technical Information of China (English)

    ZHENG Xiao-lin; LEI Yu; CHEN De-ren

    2006-01-01

    An integrated user access control method was proposed to address the issues of security and management in networked manufacturing systems (NMS).Based on the analysis of the security issues in networked manufacturing system,an integrated user access control method composed of role-based access control (RBAC),task-based access control (TBAC),relationship-driven access control (RDAC)and coalition-based access control (CBAC) was proposed,including the hierarchical user relationship model,the reference model and the process model.The elements and their relationships were defined,and the expressions of constraints authorization were given.The extensible access control markup language (XACML) was used to implement this method.This method was used in the networked manufacturing system in the Shaoxing spinning region of China.The results show that the integrated user access control method can reduce the costs of system security maintenance and management.

  15. Evaluation of a point-of-care tuberculosis test-and-treat algorithm on early mortality in people with HIV accessing antiretroviral therapy (TB Fast Track study): study protocol for a cluster randomised controlled trial.

    Science.gov (United States)

    Fielding, Katherine L; Charalambous, Salome; Hoffmann, Christopher J; Johnson, Suzanne; Tlali, Mpho; Dorman, Susan E; Vassall, Anna; Churchyard, Gavin J; Grant, Alison D

    2015-03-28

    remains an urgent need for better diagnostic tests for tuberculosis, especially for people with advanced HIV disease, which may render empirical treatment unnecessary. This trial was registered with Current Controlled Trials (identifier: ISRCTN35344604 ) on 12 September 2012.

  16. Simulations of the Impact of Controlled Mobility for Routing Protocols

    Directory of Open Access Journals (Sweden)

    Valeria Loscrí

    2010-01-01

    Full Text Available This paper addresses mobility control routing in wireless networks. Given a data flow request between a source-destination pair, the problem is to move nodes towards the best placement, such that the performance of the network is improved. Our purpose is to find the best nodes selection depending on the minimization of the maximum distance that nodes have to travel to reach their final position. We propose a routing protocol, the Routing Protocol based on Controlled Mobility (RPCM, where the chosen nodes' path minimizes the total travelled distance to reach desirable position. Specifically, controlled mobility is intended as a new design dimension network allowing to drive nodes to specific best position in order to achieve some common objectives. The main aim of this paper is to show by simulation the effectiveness of controlled mobility when it is used as a new design dimension in wireless networks. Extensive simulations are conducted to evaluate the proposed routing algorithm. Results show how our protocol outperforms a well-known routing protocol, the Ad hoc On Demand Distance Vector routing (AODV, in terms of throughput, average end-to-end data packet delay and energy spent to send a packet unit.

  17. Control room envelope unfiltered air inleakage test protocols

    Energy Technology Data Exchange (ETDEWEB)

    Lagus, P.L. [Lagus Applied Technology, San Diego, CA (United States); Grot, R.A. [Lagus Applied Technology, Olney, MD (United States)

    1997-08-01

    In 1983, the Advisory Committee on Reactor Safeguards (ACRS) recommended that the US NRC develop a control room HVAC performance testing protocol. To date no such protocol has been forthcoming. Beginning in mid-1994, an effort was funded by NRC under a Small Business Innovation Research (SBIR) grant to develop several simplified test protocols based on the principles of tracer gas testing in order to measure the total unfiltered inleakage entering a CRE during emergency mode operation of the control room ventilation system. These would allow accurate assessment of unfiltered air inleakage as required in SRP 6.4. The continuing lack of a standard protocol is unfortunate since one of the significant parameters required to calculate operator dose is the amount of unfiltered air inleakage into the control room. Often it is assumed that, if the Control Room Envelope (CRE) is maintained at +1/8 in. w.g. differential pressure relative to the surroundings, no significant unfiltered inleakage can occur it is further assumed that inleakage due to door openings is the only source of unfiltered air. 23 refs., 13 figs., 2 tabs.

  18. Integrating Attributes into Role-Based Access Control

    DEFF Research Database (Denmark)

    Mahmood Rajpoot, Qasim; Jensen, Christian D.; Krishnan, Ram

    2015-01-01

    Role-based access control (RBAC) and attribute-based access control (ABAC) are currently the most prominent access control models. However, they both suffer from limitations and have features complimentary to each other. Due to this fact, integration of RBAC and ABAC has become a hot area...

  19. Attributes Enhanced Role-Based Access Control Model

    DEFF Research Database (Denmark)

    Mahmood Rajpoot, Qasim; Jensen, Christian D.; Krishnan, Ram

    2015-01-01

    as an important area of research. In this paper, we propose an access control model that combines the two models in a novel way in order to unify their benefits. Our approach provides a fine-grained access control mechanism that not only takes contextual information into account while making the access control...

  20. MAAC: a software tool for user authentication and access control to the electronic patient record in an open distributed environment

    Science.gov (United States)

    Motta, Gustavo H.; Furuie, Sergio S.

    2004-04-01

    Designing proper models for authorization and access control for the electronic patient record (EPR) is essential to wide scale use of the EPR in large health organizations. This work presents MAAC (Middleware for Authentication and Access Control), a tool that implements a contextual role-based access control (RBAC) authorization model. RBAC regulates user"s access to computers resources based on their organizational roles. A contextual authorization uses environmental information available at access-request time, like user/patient relationship, in order to decide whether a user has the right to access an EPR resource. The software architecture where MAAC is implemented uses Lightweight Directory Access Protocol, Java programming language and the CORBA/OMG standards CORBA Security Service and Resource Access Decision Facility. With those open and distributed standards, heterogeneous EPR components can request user authentication and access authorization services in a unified and consistent fashion across multiple platforms.

  1. An Energy-Efficient, Application-Oriented Control Algorithm for MAC Protocols in WSN

    Science.gov (United States)

    Li, Deliang; Peng, Fei; Qian, Depei

    Energy efficiency has been a main concern in wireless sensor networks where Medium Access Control (MAC) protocol plays an important role. However, current MAC protocols designed for energy saving have seldom considered multiple applications coexisting in WSN with variation of traffic load dynamics and different QoS requirements. In this paper, we propose an adaptive control algorithm at MAC layer to promote energy efficiency. We focus on the tradeoff relation between collisions and control overhead as a reflection of traffic load and propose to balance the tradeoff under the constraints of QoS options. We integrate the algorithm into S-MAC and verify it through NS-2 platform. The results demonstrate the algorithm achieves observable improvement in energy performance while meeting QoS requirement for different coexisting applications in comparison with S-MAC.

  2. Messaging Performance of FIPA Interaction Protocols in Networked Embedded Controllers

    Directory of Open Access Journals (Sweden)

    Omar Jehovani López Orozco

    2007-12-01

    Full Text Available Agent-based technologies in production control systems could facilitate seamless reconfiguration and integration of mechatronic devices/modules into systems. Advances in embedded controllers which are continuously improving computational capabilities allow for software modularization and distribution of decisions. Agent platforms running on embedded controllers could hide the complexity of bootstrap and communication. Therefore, it is important to investigate the messaging performance of the agents whose main motivation is the resource allocation in manufacturing systems (i.e., conveyor system. The tests were implemented using the FIPA-compliant JADE-LEAP agent platform. Agent containers were distributed through networked embedded controllers, and agents were communicating using request and contract-net FIPA interaction protocols. The test scenarios are organized in intercontainer and intracontainer communications. The work shows the messaging performance for the different test scenarios using both interaction protocols.

  3. Messaging Performance of FIPA Interaction Protocols in Networked Embedded Controllers

    Directory of Open Access Journals (Sweden)

    García JoséAPérez

    2008-01-01

    Full Text Available Abstract Agent-based technologies in production control systems could facilitate seamless reconfiguration and integration of mechatronic devices/modules into systems. Advances in embedded controllers which are continuously improving computational capabilities allow for software modularization and distribution of decisions. Agent platforms running on embedded controllers could hide the complexity of bootstrap and communication. Therefore, it is important to investigate the messaging performance of the agents whose main motivation is the resource allocation in manufacturing systems (i.e., conveyor system. The tests were implemented using the FIPA-compliant JADE-LEAP agent platform. Agent containers were distributed through networked embedded controllers, and agents were communicating using request and contract-net FIPA interaction protocols. The test scenarios are organized in intercontainer and intracontainer communications. The work shows the messaging performance for the different test scenarios using both interaction protocols.

  4. Break-glass handling exceptional situations in access control

    CERN Document Server

    Petritsch, Helmut

    2014-01-01

    Helmut Petritsch describes the first holistic approach to Break-Glass which covers the whole life-cycle: from access control modeling (pre-access), to logging the security-relevant system state during Break-Glass accesses (at-access), and the automated analysis of Break-Glass accesses (post-access). Break-Glass allows users to override security restrictions in exceptional situations. While several Break-Glass models specific to given access control models have already been discussed in research (e.g., extending RBAC with Break-Glass), the author introduces a generic Break-Glass model. The pres

  5. Autonomous Power Control MAC Protocol for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Battery energy limitation has become a performance bottleneck for mobile ad hoc networks. IEEE 802.11 has been adopted as the current standard MAC protocol for ad hoc networks. However, it was developed without considering energy efficiency. To solve this problem, many modifications on IEEE 802.11 to incorporate power control have been proposed in the literature. The main idea of these power control schemes is to use a maximum possible power level for transmitting RTS/CTS and the lowest acceptable power for sending DATA/ACK. However, these schemes may degrade network throughput and reduce the overall energy efficiency of the network. This paper proposes autonomous power control MAC protocol (APCMP, which allows mobile nodes dynamically adjusting power level for transmitting DATA/ACK according to the distances between the transmitter and its neighbors. In addition, the power level for transmitting RTS/CTS is also adjustable according to the power level for DATA/ACK packets. In this paper, the performance of APCMP protocol is evaluated by simulation and is compared with that of other protocols.

  6. A cross-layer scheme for medium access control with QoS guaranteeing for Ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    YU Yi-fan; YIN Chang-chuan; YUE Guang-xin

    2006-01-01

    Ample medium access control (MAC) protocols for Ad hoc networks have been proposed. However, most of them do not take into account the interactions between the physical (PHY) layer and the MAC layers. Therefore, their efficiency and feasibility are greatly limited. In this article, we present a novel MAC protocol for Ad hoc networks according to the idea of cross-layer design. The proposed protocol combines an MAC protocol termed dual busy tone multiple access (DBTMA) with Orthogonal frequency division multiplexing (OFDM) system in IEEE 802.11a standard. The analysis showed that the proposed protocol provides higher throughput and is more flexible than previous MAC protocols. In addition, it can provide Quality of Service(QoS) guarantee to the packets with different delay requirements in the presence of hidden terminals.

  7. MULTIPLE ELECTRONIC CONTROL UNITS CALIBRATION SYSTEM BASED ON EXPLICIT CALIBRATION PROTOCOL AND J1939 PROTOCOL

    Institute of Scientific and Technical Information of China (English)

    YANG Shiwei; ZHU Keqing; XU Quankui; YANG Lin; ZHUO Bin

    2008-01-01

    The rising number of electronic control units (ECUs) in vehicles and the decreasing time to market have led to the need for advanced methods of calibration. A multi-ECU calibration system was developed based on the explicit calibration protocol (XCP) and J1939 communication protocol to satisfy the need of calibrating multiple ECUs simultaneously. The messages in the controller area network (CAN) are defined in the J1939 protocol. Each CAN node can get its own calibration messages and information from other ECUs, and block other messages by qualifying the CAN messages with priority, source or destination address. The data field of the calibration message is designed with the XCP , with CAN acting as the transport layer. The calibration sessions are setup with the event-triggered XCP driver in the master node and the responding XCP driver in the slave nodes. Mirroring calibration variables from ROM to RAM enables the user to calibrate ECUs online. The application example shows that the multi-ECU calibration system can calibrate multiple ECUs simultaneously, and the main program can also accomplish its calculation and send commands to the actuators in time. By the multi-ECU calibration system, the calibration effort and time can be reduced and the variables in ECU can get a better match with the variables of other ECUs.

  8. An Energy-efficient Rate Adaptive Media Access Protocol (RA-MAC for Long-lived Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wen Hu

    2010-06-01

    Full Text Available We introduce an energy-efficient Rate Adaptive Media Access Control (RA-MAC algorithm for long-lived Wireless Sensor Networks (WSNs. Previous research shows that the dynamic and lossy nature of wireless communications is one of the major challenges to reliable data delivery in WSNs. RA-MAC achieves high link reliability in such situations by dynamically trading off data rate for channel gain. The extra gain that can be achieved reduces the packet loss rate which contributes to reduced energy expenditure through a reduced numbers of retransmissions. We achieve this at the expense of raw bit rate which generally far exceeds the application’s link requirement. To minimize communication energy consumption, RA-MAC selects the optimal data rate based on the estimated link quality at each data rate and an analytical model of the energy consumption. Our model shows how the selected data rate depends on different channel conditions in order to minimize energy consumption. We have implemented RA-MAC in TinyOS for an off-the-shelf sensor platform (the TinyNode on top of a state-of-the-art WSN Media Access Control Protocol, SCP-MAC, and evaluated its performance by comparing our implementation with the original SCP-MAC using both simulation and experiment.

  9. Secure Access Control and Authority Delegation Based on Capability and Context Awareness for Federated IoT

    DEFF Research Database (Denmark)

    Anggorojati, Bayu; Mahalle, Parikshit N.; Prasad, Neeli R.

    2013-01-01

    Access control is a critical functionality in Internet of Things (IoT), and it is particularly promising to make access control secure, efficient and generic in a distributed environment. Another an important property of access control system in the IoT is flexibility which can be achieved...... by access or authority delegation. Delegation mechanisms in access control that have been studied until now have been intended mainly for a system that has no resource constraint, such as a web-based system, which is not very suitable for a highly pervasive system such as IoT. This chapter presents...... the Capability-based Context Aware Access Control (CCAAC) model including the authority delegation method, along with specification and protocol evaluation intended for federated Machine-to-Machine (M2M)/IoT. By using the identity and capability-based access control approach together with the contextual...

  10. Context-Based E-Health System Access Control Mechanism

    Science.gov (United States)

    Al-Neyadi, Fahed; Abawajy, Jemal H.

    E-Health systems logically demand a sufficiently fine-grained authorization policy for access control. The access to medical information should not be just role-based but should also include the contextual condition of the role to access data. In this paper, we present a mechanism to extend the standard role-based access control to incorporate contextual information for making access control decisions in e-health application. We present an architecture consisting of authorisation and context infrastructure that work cooperatively to grant access rights based on context-aware authorization policies and context information.

  11. An application-layer based centralized information access control for VPN

    Institute of Scientific and Technical Information of China (English)

    OUYANG Kai; ZHOU Jing-li; XIA Tao; YU Sheng-sheng

    2006-01-01

    With the rapid development of Virtual Private Network (VPN), many companies and organizations use VPN to implement their private communication. Traditionally, VPN uses security protocols to protect the confidentiality of data, the message integrity and the endpoint authentication. One core technique of VPN is tunneling, by which clients can access the internal servers traversing VPN. However, the tunneling technique also introduces a concealed security hole. It is possible that ifone vicious user can establish tunneling by the VPN server, he can compromise the internal servers behind the VPN server. So this paper presents a novel Application-layer based Centralized Information Access Control (ACIAC) for VPN to solve this problem.To implement an efficient, flexible and multi-decision access control model, we present two key techniques to ACIAC-the centralized management mechanism and the stream-based access control. Firstly, we implement the information center and the constraints/events center for ACIAC. By the two centers, we can provide an abstract access control mechanism, and the material access control can be decided dynamically by the ACIAC's constraint/event mechanism. Then we logically classify the VPN communication traffic into the access stream and the data stream so that we can tightly couple the features of VPN communication with the access control model. We also provide the design of our ACIAC prototype in this paper.

  12. Extending OPeNDAP's Data-Access Protocol to Include Enhanced Pre-Retrieval Operations

    Science.gov (United States)

    Fulker, D. W.

    2013-12-01

    We describe plans to extend OPeNDAP's Web-services protocol as a Building Block for NSF's EarthCube initiative. Though some data-access services have offered forms of subset-selection for decades, other pre-retrieval operations have been unavailable, in part because their benefits (over equivalent post-retrieval actions) are only now becoming fully evident. This is due in part to rapid growth in the volumes of data that are pertinent to the geosciences, exacerbated by limitations such as Internet speeds and latencies as well as pressures toward data usage on ever-smaller devices. In this context, as recipients of a "Building Blocks" award from the most recent round of EarthCube funding, we are launching the specification and prototype implementation of a new Open Data Services Invocation Protocol (ODSIP), by which clients may invoke a newly rich set of data-acquisition services, ranging from statistical summarization and criteria-driven subsetting to re-gridding/resampling. ODSIP will be an extension to DAP4, the latest version of OPeNDAP's widely used data access protocol, which underpins a number of open-source, multilingual, client-server systems (offering data access as a Web service), including THREDDS, PyDAP, GrADS, ERDAP and FERRET, as well as OPeNDAP's own Hyrax servers. We are motivated by the idea that key parts of EarthCube can be built effectively around clients and servers that employ a common and conceptually rich protocol for data acquisition. This concept extends 'data provision' to include pre-retrieval operations that, even when invoked by remote clients, exhibit efficiencies of data-proximate computation. Our aim for ODSIP is to embed a largely domain-neutral algebra of server functions that, despite being deliberately compact, can fulfill a broad range of user needs for pre-retrieval operations. To that end, our approach builds upon languages and tools that have proven effective in multi-domain contexts, and we will employ a user-centered design

  13. Formats and Network Protocols for Browser Access to 2D Raster Data

    Science.gov (United States)

    Plesea, L.

    2015-12-01

    Tiled web maps in browsers are a major success story, forming the foundation of many current web applications. Enabling tiled data access is the next logical step, and is likely to meet with similar success. Many ad-hoc approaches have already started to appear, and something similar is explored within the Open Geospatial Consortium. One of the main obstacles in making browser data access a reality is the lack of a well-known data format. This obstacle also represents an opportunity to analyze the requirements and possible candidates, applying lessons learned from web tiled image services and protocols. Similar to the image counterpart, a web tile raster data format needs to have good intrinsic compression and be able to handle high byte count data types including floating point. An overview of a possible solution to the format problem, a 2D data raster compression algorithm called Limited Error Raster Compression (LERC) will be presented. In addition to the format, best practices for high request rate HTTP services also need to be followed. In particular, content delivery network (CDN) caching suitability needs to be part of any design, not an after-thought. Last but not least, HTML 5 browsers will certainly be part of any solution since they provide improved access to binary data, as well as more powerful ways to view and interact with the data in the browser. In a simple but relevant application, digital elevation model (DEM) raster data is served as LERC compressed data tiles which are used to generate terrain by a HTML5 scene viewer.

  14. Remote control of the industry processes. POWERLINK protocol application

    Science.gov (United States)

    Wóbel, A.; Paruzel, D.; Paszkiewicz, B.

    2017-08-01

    The present technological development enables the use of solutions characterized by a lower failure rate, and work with greater precision. This allows you to obtain the most efficient production, high speed production and reliability of individual components. The main scope of this article was POWERLINK protocol application for communication with the controller B & R through communication Ethernet for recording process parameters. This enables control of run production cycle using an internal network connected to the PC industry. Knowledge of the most important parameters of the production in real time allows detecting of a failure immediately after occurrence. For this purpose, the position of diagnostic use driver X20CP1301 B&R to record measurement data such as pressure, temperature valve between the parties and the torque required to change the valve setting was made. The use of POWERLINK protocol allows for the transmission of information on the status of every 200 μs.

  15. Implementation of a control protocol in the instrumentation field

    Science.gov (United States)

    Benincasa, G.; Casalegno, L.; Gelato, G.; Kouzmenko, V.; Odier, P.

    1990-08-01

    An operational protocol for controlling power converters and beam-instrumentation devices has been proposed at CERN. This is presented in another paper at this conference. A single operational model for a class of devices permits the definition of a unique set of control functions that must be exchanged between the control system and the specific device: the parameters of these functions are contained in messages of standard format. Although these definitions are independent of the controls architecture, an actual implementation must be tailored to match an existing control system. Our first implementation has been developed in the context of the CERN PS control system and concerns a set of four current-beam transformers of the PS Booster. In this paper we describe in particular the hardware and software development for the specific device anthe software control module that is general for a family of devices in the PS complex. The claimed advantages of using the protocol are discussed, i.e. the total independence between the control system and specific device implementation, the clean separation of responsibilities and the portability of devices.

  16. Implementation of a control protocol in the instrumentation field

    Energy Technology Data Exchange (ETDEWEB)

    Benincasa, G.; Casalegno, L.; Gelato, G.; Kouzmenko, V.; Odier, P. (European Organization for Nuclear Research, Geneva (Switzerland). LEP Div.)

    1990-08-01

    An operational protocol for controlling power converters and beam-instrumentation devices has been proposed at CERN. This is presented in another paper at this conference. A single operational model for a class of devices permits the definition of a unique set of control functions that must be exchanged between the control system and the specific device: the parameters of these functions are contained in messages of standard format. Although these definitions are independent of the controls architecture, an actual implementation must be tailored to match an existing control system. Our first implementation has been developed in the context of the CERN PS control system and concerns a set of four current-beam transformers of the PS Booster. In this paper we describe in particular the hardware and software development for the specific device and the software control module that is general for a family of devices in the PS complex. The claimed advantages of using the protocol are discussed, i.e. the total independence between the control system and specific device implementation, the clean separation of responsibilities and the portability of devices. (orig.).

  17. Energy Analysis of Contention Tree-Based Access Protocols in Dense Machine-to-Machine Area Networks

    Directory of Open Access Journals (Sweden)

    Francisco Vázquez-Gallego

    2015-01-01

    Full Text Available Machine-to-Machine (M2M area networks aim at connecting an M2M gateway with a large number of energy-constrained devices that must operate autonomously for years. Therefore, attaining high energy efficiency is essential in the deployment of M2M networks. In this paper, we consider a dense M2M area network composed of hundreds or thousands of devices that periodically transmit data upon request from a gateway or coordinator. We theoretically analyse the devices’ energy consumption using two Medium Access Control (MAC protocols which are based on a tree-splitting algorithm to resolve collisions among devices: the Contention Tree Algorithm (CTA and the Distributed Queuing (DQ access. We have carried out computer-based simulations to validate the accuracy of the theoretical models and to compare the energy performance using DQ, CTA, and Frame Slotted-ALOHA (FSA in M2M area networks with devices in compliance with the IEEE 802.15.4 physical layer. Results show that the performance of DQ is totally independent of the number of contending devices, and it can reduce the energy consumed per device in more than 35% with respect to CTA and in more than 80% with respect to FSA.

  18. Streetlight Control System Based on Wireless Communication over DALI Protocol

    Directory of Open Access Journals (Sweden)

    Francisco José Bellido-Outeiriño

    2016-04-01

    Full Text Available Public lighting represents a large part of the energy consumption of towns and cities. Efficient management of public lighting can entail significant energy savings. This work presents a smart system for managing public lighting networks based on wireless communication and the DALI protocol. Wireless communication entails significant economic savings, as there is no need to install new wiring and visual impacts and damage to the facades of historical buildings in city centers are avoided. The DALI protocol uses bidirectional communication with the ballast, which allows its status to be controlled and monitored at all times. The novelty of this work is that it tackles all aspects related to the management of public lighting: a standard protocol, DALI, was selected to control the ballast, a wireless node based on the IEEE 802.15.4 standard with a DALI interface was designed, a network layer that considers the topology of the lighting network has been developed, and lastly, some user-friendly applications for the control and maintenance of the system by the technical crews of the different towns and cities have been developed.

  19. Streetlight Control System Based on Wireless Communication over DALI Protocol.

    Science.gov (United States)

    Bellido-Outeiriño, Francisco José; Quiles-Latorre, Francisco Javier; Moreno-Moreno, Carlos Diego; Flores-Arias, José María; Moreno-García, Isabel; Ortiz-López, Manuel

    2016-04-27

    Public lighting represents a large part of the energy consumption of towns and cities. Efficient management of public lighting can entail significant energy savings. This work presents a smart system for managing public lighting networks based on wireless communication and the DALI protocol. Wireless communication entails significant economic savings, as there is no need to install new wiring and visual impacts and damage to the facades of historical buildings in city centers are avoided. The DALI protocol uses bidirectional communication with the ballast, which allows its status to be controlled and monitored at all times. The novelty of this work is that it tackles all aspects related to the management of public lighting: a standard protocol, DALI, was selected to control the ballast, a wireless node based on the IEEE 802.15.4 standard with a DALI interface was designed, a network layer that considers the topology of the lighting network has been developed, and lastly, some user-friendly applications for the control and maintenance of the system by the technical crews of the different towns and cities have been developed.

  20. Serial Interface through Stream Protocol on EPICS Platform for Distributed Control and Monitoring

    Science.gov (United States)

    Das Gupta, Arnab; Srivastava, Amit K.; Sunil, S.; Khan, Ziauddin

    2017-04-01

    Remote operation of any equipment or device is implemented in distributed systems in order to control and proper monitoring of process values. For such remote operations, Experimental Physics and Industrial Control System (EPICS) is used as one of the important software tool for control and monitoring of a wide range of scientific parameters. A hardware interface is developed for implementation of EPICS software so that different equipment such as data converters, power supplies, pump controllers etc. could be remotely operated through stream protocol. EPICS base was setup on windows as well as Linux operating system for control and monitoring while EPICS modules such as asyn and stream device were used to interface the equipment with standard RS-232/RS-485 protocol. Stream Device protocol communicates with the serial line with an interface to asyn drivers. Graphical user interface and alarm handling were implemented with Motif Editor and Display Manager (MEDM) and Alarm Handler (ALH) command line channel access utility tools. This paper will describe the developed application which was tested with different equipment and devices serially interfaced to the PCs on a distributed network.

  1. The U.S. Culture Collection Network Responding to the Requirements of the Nagoya Protocol on Access and Benefit Sharing

    Science.gov (United States)

    Kevin McCluskey; Katharine B. Barker; Hazel A. Barton; Kyria Boundy-Mills; Daniel R. Brown; Jonathan A. Coddington; Kevin Cook; Philippe Desmeth; David Geiser; Jessie A. Glaeser; Stephanie Greene; Seogchan Kang; Michael W. Lomas; Ulrich Melcher; Scott E. Miller; David R. Nobles; Kristina J. Owens; Jerome H. Reichman; Manuela da Silva; John Wertz; Cale Whitworth; David Smith; Steven E. Lindow

    2017-01-01

    The U.S. Culture Collection Network held a meeting to share information about how culture collections are responding to the requirements of the recently enacted Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization to the Convention on Biological Diversity (CBD). The meeting included representatives...

  2. The US Culture Collection Network responding to the requirements of the Nagoya Protocol on Access and Benefit Sharing

    Science.gov (United States)

    The US Culture Collection Network held a meeting to share information about how collections are responding to the requirements of the recently enacted Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization to the Convention on Bio...

  3. Burstiness-Aware Congestion Control Protocol for Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    Liang Lulu; Gao Deyun; Qin Yajuan; Zhang Hongke

    2011-01-01

    In monitoring Wireless Sensor Networks (WSNs),the traffic usually has bursty characteristics when an event occurs.Transient congestion would increase delay and packet loss rate severely,which greatly reduces network performance.To solve this problem,we propose a Burstiness-aware Congestion.Control Protocol (BCCP) for wireless sensor networks.In BCCP,the backoff delay is adopted as a congestion indication.Normally,sensor nodes work on contention-based MAC protocol (such as CSMA/CA).However,when congestion occurs,localized TDMA instead of CSMA/CA is embedded into the nodes around the congestion area.Thus,the congestion nodes only deliver their data during their assigned slots to alleviate the contention-caused congestion.Finally,we implement BCCP in our sensor network testbed.The experiment results show that BCCP could detect area congestion in time,and improve the network performance significantly in terms of delay and packet loss rate.

  4. Security analysis and improvements of authentication and access control in the Internet of Things.

    Science.gov (United States)

    Ndibanje, Bruce; Lee, Hoon-Jae; Lee, Sang-Gon

    2014-08-13

    Internet of Things is a ubiquitous concept where physical objects are connected over the internet and are provided with unique identifiers to enable their self-identification to other devices and the ability to continuously generate data and transmit it over a network. Hence, the security of the network, data and sensor devices is a paramount concern in the IoT network as it grows very fast in terms of exchanged data and interconnected sensor nodes. This paper analyses the authentication and access control method using in the Internet of Things presented by Jing et al. (Authentication and Access Control in the Internet of Things. In Proceedings of the 2012 32nd International Conference on Distributed Computing Systems Workshops, Macau, China, 18-21 June 2012, pp. 588-592). According to our analysis, Jing et al.'s protocol is costly in the message exchange and the security assessment is not strong enough for such a protocol. Therefore, we propose improvements to the protocol to fill the discovered weakness gaps. The protocol enhancements facilitate many services to the users such as user anonymity, mutual authentication, and secure session key establishment. Finally, the performance and security analysis show that the improved protocol possesses many advantages against popular attacks, and achieves better efficiency at low communication cost.

  5. Energy efficient medium access protocol for wireless medical body area sensor networks.

    Science.gov (United States)

    Omeni, O; Wong, A; Burdett, A J; Toumazou, C

    2008-12-01

    This paper presents a novel energy-efficient MAC Protocol designed specifically for wireless body area sensor networks (WBASN) focused towards pervasive healthcare applications. Wireless body area networks consist of wireless sensor nodes attached to the human body to monitor vital signs such as body temperature, activity or heart-rate. The network adopts a master-slave architecture, where the body-worn slave node periodically sends sensor readings to a central master node. Unlike traditional peer-to-peer wireless sensor networks, the nodes in this biomedical WBASN are not deployed in an ad hoc fashion. Joining a network is centrally managed and all communications are single-hop. To reduce energy consumption, all the sensor nodes are in standby or sleep mode until the centrally assigned time slot. Once a node has joined a network, there is no possibility of collision within a cluster as all communication is initiated by the central node and is addressed uniquely to a slave node. To avoid collisions with nearby transmitters, a clear channel assessment algorithm based on standard listen-before-transmit (LBT) is used. To handle time slot overlaps, the novel concept of a wakeup fallback time is introduced. Using single-hop communication and centrally controlled sleep/wakeup times leads to significant energy reductions for this application compared to more ldquoflexiblerdquo network MAC protocols such as 802.11 or Zigbee. As duty cycle is reduced, the overall power consumption approaches the standby power. The protocol is implemented in hardware as part of the Sensiumtrade system-on-chip WBASN ASIC, in a 0.13- mum CMOS process.

  6. Microcontroller Protocol for Secure Broadcast in Controller Area Networks

    Directory of Open Access Journals (Sweden)

    B.Vijayalakshmi

    2014-04-01

    Full Text Available Controller Area Network is a bus commonly used by controllers inside vehicles and in various industrial control applications. In the past controllers were assumed to operate in secure perimeters, but today these environments are well connected to the outside world and recent incidents showed them extremely vulnerable to cyber-attacks. To withstand such threats, one can implement security in the application layer of CAN. Here we design, refine and implement a broadcast authentication protocol based on the well known paradigm of using key-chains and time synchronization, a commonly used Mechanism in wireless sensor networks, which allows us to take advantage from the use of symmetric primitives without the need of secret shared keys during broadcast. But, as process control is a time critical operation we make several refinements in order to improve on the authentication delay. For this we study several trade-offs to alleviate shortcomings on computational speed, memory and bandwidth up to the point of using reduced versions of hash functions that can assure ad hoc security. To prove the efficiency of the protocol

  7. Game-theory Model based on Carrier Sense Multiple Access Protocol in Wireless Network

    Directory of Open Access Journals (Sweden)

    Jun Tian

    2014-06-01

    Full Text Available In order to solve game-theory model problem based on carrier sense multiple access protocol with collision avoidance in wireless network, a game-theory-based general and compatible modeling process is proposed, where the transmission probability of a node in a slot time is regarded as mixed game and network performance parameter M is taken as revenue function of game so as to build M rounds non-cooperative mixed strategy game with N gamers. After performing M rounds game, it will acquire M Nash-equilibria which is not equal to each other, and then these Nash-equilibria are taken as the input of single objective programming model with many constraints so as to obtain compromise equilibria. Finally, a minimum contention window based on compromise equilibria is designed. The throughput and successful transmission rate are analyzed through the simulation, and the simulation experiment results show our proposed modeling process has the more throughputs and the lower drop performance than the existing methods.

  8. Assessing health systems for type 1 diabetes in sub-Saharan Africa: developing a 'Rapid Assessment Protocol for Insulin Access'

    Directory of Open Access Journals (Sweden)

    de Courten Maximilian

    2006-02-01

    Full Text Available Abstract Background In order to improve the health of people with Type 1 diabetes in developing countries, a clear analysis of the constraints to insulin access and diabetes care is needed. We developed a Rapid Assessment Protocol for Insulin Access, comprising a series of questionnaires as well as a protocol for the gathering of other data through site visits, discussions, and document reviews. Methods The Rapid Assessment Protocol for Insulin Access draws on the principles of Rapid Assessment Protocols which have been developed and implemented in several different areas. This protocol was adapted through a thorough literature review on diabetes, chronic condition management and medicine supply in developing countries. A visit to three countries in sub-Saharan Africa and meetings with different experts in the field of diabetes helped refine the questionnaires. Following the development of the questionnaires these were tested with various people familiar with diabetes and/or healthcare in developing countries. The Protocol was piloted in Mozambique then refined and had two further iterations in Zambia and Mali. Translations of questionnaires were made into local languages when necessary, with back translation to ensure precision. Results In each country the protocol was implemented in 3 areas – the capital city, a large urban centre and a predominantly rural area and their respective surroundings. Interviews were carried out by local teams trained on how to use the tool. Data was then collected and entered into a database for analysis. Conclusion The Rapid Assessment Protocol for Insulin Access was developed to provide a situational analysis of Type 1 diabetes, in order to make recommendations to the national Ministries of Health and Diabetes Associations. It provided valuable information on patients' access to insulin, syringes, monitoring and care. It was thus able to sketch a picture of the health care system with regards to its ability to

  9. Open versus Controlled-Access Data | Office of Cancer Genomics

    Science.gov (United States)

    OCG employs stringent human subjects’ protection and data access policies to protect the privacy and confidentiality of the research participants. Depending on the risk of patient identification, OCG programs data are available to the scientific community in two tiers: open or controlled access. Both types of data can be accessed through its corresponding OCG program-specific data matrix or portal. Open-access Data

  10. Practical Physiological Monitoring Protocol for Heat Strain Control

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R B; Johnson, J S; Burastero, S R; Gilmore, O

    2003-07-01

    This protocol is indicated when employees are: (1) Exposed to Heat Stress above the TLV; (2) Performing low to moderate work rates with rare excursions to heavy rates; NOT for heavy and very heavy work rates or requiring peak outputs for extended periods; and, (3) Determined to need physiological heat strain monitoring by the cognizant Industrial Hygienist. The requirements are: (1) A work/rest regimen must be established at outset and adjusted as needed during operations (see Appendix A); (2) On-going data collection and review; (3) Rest times must be increased if indicated; (4) Intended for normal, healthy adults. Seasonal medical screening is recommended; and (5) Training for affected employees regarding this protocol, hydration, self-limitation, lifestyle effects and signs, symptoms and treatment of heat related illnesses. This protocol is to aid industrial hygienists in assessing individual physiological response to employee heat exposures, and provides guidance to identify and reduce heat strain as needed. Physiological monitoring is recommended when heat exposure exceeds the TLV by {ge} 2 C and/or when evaporative cooling is limited or eliminated. Typically, this occurs when the use of personal protective equipment includes impermeable or water vapor restrictive outer garments. This protocol is used to identify when heat strain may be excessive. This is determined through measurements taken during each rest period. If decision criteria are exceeded, changes in work practices shall be implemented immediately to reduce employee heat strain and prevent heat related illnesses up to and including heat stroke, a life threatening condition. This protocol may not be appropriate under all conditions. Sound Industrial Hygiene professional judgment is required. Because the measurements for this protocol occur during the rest phase of the work/rest regimen, the conditions affecting employee heat strain during the work phase must be carefully weighed. Work rate

  11. Accession of Pakistan to the 1951 Convention and 1967 Protocol relating to the Status of Refugees: 'Signing on could make all the difference’

    NARCIS (Netherlands)

    Zieck, M.Y.A.

    2010-01-01

    One of the means UNHCR uses to attract accessions is a brochure entitled: "The 1951 Convention relating to the Status of Refugees and its 1967 Protocol. Signing on Could Make All the Difference". Accession to the 1951 Convention and its 1967 Protocol would indeed make a difference, but not just the

  12. Medium Access Control for Wireless Sensor Networks based on Impulse Radio Ultra Wideband

    CERN Document Server

    Berthe, Abdoulaye; Dragomirescu, Daniela; Plana, Robert

    2010-01-01

    This paper describes a detailed performance evaluation of distributed Medium Access Control (MAC) protocols for Wireless Sensor Networks based on Impulse Radio Ultra Wideband (IR-UWB) Physical layer (PHY). Two main classes of Medium Access Control protocol have been considered: Slotted and UnSlotted with reliability. The reliability is based on Automatic Repeat ReQuest (ARQ). The performance evaluation is performed using a complete Wireless Sensor Networks (WSN) simulator built on the Global Mobile Information System Simulator (GloMoSim). The optimal operating parameters are first discussed for IR-UWB in terms of slot size, retransmission delay and the number of retransmission, then a comparison between IR-UWB and other transmission techniques in terms of reliability latency and power efficiency.

  13. Impact of Transport Layer Protocols on Reliable Information Access in Smart Grids

    DEFF Research Database (Denmark)

    Shahid, Kamal; Saeed, Aamir; Kristensen, Thomas le Fevre

    2017-01-01

    Time is critical for certain types of dynamic information (e.g. frequency control) in a smart grid scenario. The usefulness of such information depends upon the arrival within a specific frame of time, which in other case may not serve the purpose and effect controller’s performance......-to-end delays at the cost of unreliable, best-effort data transportation service. The research question raised in this paper is thus, which is preferred for the delay-critical applications of smart grids, and to what degree of packet losses and round trip times, TCP is preferable to UDP and vice versa...... of events at grid assets as well as the information update strategy in one single metric which otherwise is not very intuitive and difficult to allow a similar useful comparison. Further, the analysis is concluded by providing a clear guide on the selection of the transport protocol to meet application...

  14. Law-Aware Access Control and its Information Model

    CERN Document Server

    Stieghahn, Michael

    2010-01-01

    Cross-border access to a variety of data such as market information, strategic information, or customer-related information defines the daily business of many global companies, including financial institutions. These companies are obliged by law to keep a data processing legal for all offered services. They need to fulfill different security objectives specified by the legislation. Therefore, they control access to prevent unauthorized users from using data. Those security objectives, for example confidentiality or secrecy, are often defined in the eXtensible Access Control Markup Language that promotes interoperability between different systems. In this paper, we show the necessity of incorporating the requirements of legislation into access control. Based on the work flow in a banking scenario we describe a variety of available contextual information and their interrelations. Different from other access control systems our main focus is on law-compliant cross-border data access. By including legislation dir...

  15. Distributed Role-based Access Control for Coaliagion Application

    Institute of Scientific and Technical Information of China (English)

    HONG Fan; ZHU Xian; XING Guanglin

    2005-01-01

    Access control in multi-domain environments is one of the important questions of building coalition between domains.On the basis of RBAC access control model, the concepts of role delegation and role mapping are proposed, which support the third-party authorization.Then, a distributed RBAC model is presented.Finally the implementation issues are discussed.

  16. 49 CFR 1542.207 - Access control systems.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Access control systems. 1542.207 Section 1542.207..., DEPARTMENT OF HOMELAND SECURITY CIVIL AVIATION SECURITY AIRPORT SECURITY Operations § 1542.207 Access control systems. (a) Secured area. Except as provided in paragraph (b) of this section, the measures...

  17. Privacy Enhanced Access Control by Means of Policy Blinding

    NARCIS (Netherlands)

    Sedghi, Saeed; Hartel, Pieter; Jonker, Willem; Nikova, Svetla; Bao, Feng; Weng, Jian

    2011-01-01

    Traditional techniques of enforcing an access control policy rely on an honest reference monitor to enforce the policy. However, for applications where the resources are sensitive, the access control policy might also be sensitive. As a result, an honest-but-curious reference monitor would glean som

  18. Dynamic User Role Assignment in Remote Access Control

    NARCIS (Netherlands)

    Saffarian, Mohsen; Tang, Qiang; Jonker, Willem; Hartel, Pieter

    2009-01-01

    The Role-Based Access Control (RBAC) model has been widely applied to a single domain in which users are known to the administrative unit of that domain, beforehand. However, the application of the conventional RBAC model for remote access control scenarios is not straightforward. In such scenarios,

  19. Analysis of Access Control Policies in Operating Systems

    Science.gov (United States)

    Chen, Hong

    2009-01-01

    Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the…

  20. Dynamic User Role Assignment in Remote Access Control

    NARCIS (Netherlands)

    Saffarian, M.; Tang, Qiang; Jonker, Willem; Hartel, Pieter H.

    2009-01-01

    The Role-Based Access Control (RBAC) model has been widely applied to a single domain in which users are known to the administrative unit of that domain, beforehand. However, the application of the conventional RBAC model for remote access control scenarios is not straightforward. In such scenarios,

  1. Analysis of Access Control Policies in Operating Systems

    Science.gov (United States)

    Chen, Hong

    2009-01-01

    Operating systems rely heavily on access control mechanisms to achieve security goals and defend against remote and local attacks. The complexities of modern access control mechanisms and the scale of policy configurations are often overwhelming to system administrators and software developers. Therefore, mis-configurations are common, and the…

  2. Cognitive radio networks medium access control for coexistence of wireless systems

    CERN Document Server

    Bian, Kaigui; Gao, Bo

    2014-01-01

    This book gives a comprehensive overview of the medium access control (MAC) principles in cognitive radio networks, with a specific focus on how such MAC principles enable different wireless systems to coexist in the same spectrum band and carry out spectrum sharing.  From algorithm design to the latest developments in the standards and spectrum policy, readers will benefit from leading-edge knowledge of how cognitive radio systems coexist and share spectrum resources.  Coverage includes cognitive radio rendezvous, spectrum sharing, channel allocation, coexistence in TV white space, and coexistence of heterogeneous wireless systems.   • Provides a comprehensive reference on medium access control (MAC)-related problems in the design of cognitive radio systems and networks; • Includes detailed analysis of various coexistence problems related to medium access control in cognitive radio networks; • Reveals novel techniques for addressing the challenges of coexistence protocol design at a higher level ...

  3. An improved arbitrated quantum signature protocol based on the key-controlled chained CNOT encryption

    Science.gov (United States)

    Zhang, Long; Sun, Hong-Wei; Zhang, Ke-Jia; Jia, Heng-Yue

    2017-03-01

    In this paper, a new quantum encryption based on the key-controlled chained CNOT operations, which is named KCCC encryption, is proposed. With the KCCC encryption, an improved arbitrated quantum signature (AQS) protocol is presented. Compared with the existing protocols, our protocol can effectively prevent forgery attacks and disavowal attacks. Moreover, only single state is required in the protocol. We hope it is helpful to further research in the design of AQS protocols in future.

  4. A Model of Workflow-oriented Attributed Based Access Control

    Directory of Open Access Journals (Sweden)

    Guoping Zhang

    2011-02-01

    Full Text Available the emergence of “Internet of Things” breaks previous traditional thinking, which integrates physical infrastructure and network infrastructure into unified infrastructure. There will be a lot of resources or information in IoT, so computing and processing of information is the core supporting of IoT. In this paper, we introduce “Service-Oriented Computing” to solve the problem where each device can offer its functionality as standard services. Here we mainly discuss the access control issue of service-oriented computing in Internet of Things. This paper puts forward a model of Workflow-oriented Attributed Based Access Control (WABAC, and design an access control framework based on WABAC model. The model grants permissions to subjects according to subject atttribute, resource attribute, environment attribute and current task, meeting access control request of SOC. Using the approach presented can effectively enhance the access control security for SOC applications, and prevent the abuse of subject permissions.

  5. A novel and efficient user access control scheme for wireless body area sensor networks

    Directory of Open Access Journals (Sweden)

    Santanu Chatterjee

    2014-07-01

    Full Text Available Wireless body area networks (WBANs can be applied to provide healthcare and patient monitoring. However, patient privacy can be vulnerable in a WBAN unless security is considered. Access to authorized users for the correct information and resources for different services can be provided with the help of efficient user access control mechanisms. This paper proposes a new user access control scheme for a WBAN. The proposed scheme makes use of a group-based user access ID, an access privilege mask, and a password. An elliptic curve cryptography-based public key cryptosystem is used to ensure that a particular legitimate user can only access the information for which he/she is authorized. We show that our scheme performs better than previously existing user access control schemes. Through a security analysis, we show that our scheme is secure against possible known attacks. Furthermore, through a formal security verification using the AVISPA (Automated Validation of Internet Security Protocols and Applications tool, we show that our scheme is also secure against passive and active attacks.

  6. ADNP-CSMA Random Multiple Access protocol application with the function of monitoring in Ad Hoc network

    Directory of Open Access Journals (Sweden)

    Zhan Gang

    2016-01-01

    Full Text Available In Ad Hoc networks,the net work of mobile nodes exchange information with their wireless transceiver equipment,the network throughput is in increased,compared to other such multiple hops network.Moreover along with the rapid development of modern information,communication business also will be increase.However,the access and adaptive of previous CSMA protocol are insufficient.According to these properties,this paper presents a kind of adaptive dual clock with monitoring function P-CSMA random multiple access protocol(ADNP-CSMA,and discusses two kinds of P-CSMA.ACK with monitoring function is introduced to maintain the stability of the whole system,and the introduction of dual clock mechanism reduces the channel of idle period.It calculate the system throughput expression through the method of average period,and the simulation results show that the system is constant in the case of high load throughput.

  7. Telemonitoring and Protocolized Case Management for Hypertensive Community-Dwelling Seniors With Diabetes: Protocol of the TECHNOMED Randomized Controlled Trial.

    Science.gov (United States)

    Padwal, Raj; McAlister, Finlay Aleck; Wood, Peter William; Boulanger, Pierre; Fradette, Miriam; Klarenbach, Scott; Edwards, Alun L; Holroyd-Leduc, Jayna M; Alagiakrishnan, Kannayiram; Rabi, Doreen; Majumdar, Sumit Ranjan

    2016-06-24

    Diabetes and hypertension are devastating, deadly, and costly conditions that are very common in seniors. Controlling hypertension in seniors with diabetes dramatically reduces hypertension-related complications. However, blood pressure (BP) must be lowered carefully because seniors are also susceptible to low BP and attendant harms. Achieving "optimal BP control" (ie, avoiding both undertreatment and overtreatment) is the ultimate therapeutic goal in such patients. Regular BP monitoring is required to achieve this goal. BP monitoring at home is cheap, convenient, widely used, and guideline endorsed. However, major barriers prevent proper use. These may be overcome through use of BP telemonitoring-the secure teletransmission of BP readings to a health portal, where BP data are summarized for provider and patient use, with or without protocolized case management. To examine the incremental effectiveness, safety, cost-effectiveness, usability, and acceptability of home BP telemonitoring, used with or without protocolized case management, compared with "enhanced usual care" in community-dwelling seniors with diabetes and hypertension. A 300-patient, 3-arm, pragmatic randomized controlled trial with blinded outcome ascertainment will be performed in seniors with diabetes and hypertension living independently in seniors' residences in greater Edmonton. Consenting patients will be randomized to usual care, home BP telemonitoring alone, or home BP telemonitoring plus protocolized pharmacist case management. Usual care subjects will receive a home BP monitor but neither they nor their providers will have access to teletransmitted data. In both telemonitored arms, providers will receive telemonitored BP data summaries. In the case management arm, pharmacist case managers will be responsible for reviewing teletransmitted data and initiating guideline-concordant and protocolized changes in BP management. Outcomes will be ascertained at 6 and 12 months. Within-study-arm change

  8. Session Initiation Protocol (SIP) Server Overload Control: Design and Evaluation

    CERN Document Server

    Shen, Charles; Nahum, Erich

    2008-01-01

    A Session Initiation Protocol (SIP) server may be overloaded by emergency-induced call volume, ``American Idol'' style flash crowd effects or denial of service attacks. The SIP server overload problem is interesting especially because the costs of serving or rejecting a SIP session can be similar. For this reason, the built-in SIP overload control mechanism based on generating rejection messages cannot prevent the server from entering congestion collapse under heavy load. The SIP overload problem calls for a pushback control solution in which the potentially overloaded receiving server may notify its upstream sending servers to have them send only the amount of load within the receiving server's processing capacity. The pushback framework can be achieved by either a rate-based feedback or a window-based feedback. The centerpiece of the feedback mechanism is the algorithm used to generate load regulation information. We propose three new window-based feedback algorithms and evaluate them together with two exis...

  9. On the performance of shared access control strategy for femtocells

    KAUST Repository

    Magableh, Amer M.

    2013-02-18

    Femtocells can be employed in cellular systems to enhance the indoor coverage, especially in the areas with high capacity growing demands and high traffic rates. In this paper, we propose an efficient resource utilization protocol, named as shared access protocol (SAP), to enable the unauthorized macrocell user equipment to communicate with partially closed-access femtocell base station to improve and enhance the system performance. The system model considers a femtocell that is equipped with a total of N separated antennas or channels to multiplex independent traffic. Then, a set of N1 channels is used for closed access only by the authorized users, and the remaining set of channel resources can be used for open access by either authorized or unauthorized users upon their demands and spatial locations. For this system model, we obtain the signal-to-interference ratio characteristics, such as the distribution and the moment generating function, in closed forms for two fading models of indoor and outdoor environments. The signal-tointerference ratio statistics are then used to derive some important performance measures of the proposed SAP in closed form, such as the average bit error rate, outage probability, and average channel capacity for the two fading models under consideration. Numerical results for the obtained expressions are provided and supported by Monte Carlo simulations to validate the analytical development and study the effectiveness of the proposed SAP under different conditions. Copyright © 2012 John Wiley and Sons, Ltd.

  10. An Arbitrary 2D Structured Replica Control Protocol

    OpenAIRE

    Basmadjian, Robert; Meer, Hermann,

    2011-01-01

    Traditional replication protocols that logically arrange the replicas into a specific structure have reasonable availability, lower communication cost as well as system load than those that do not require any logical organisation of replicas. We propose in this paper the A2DS protocol: a single protocol that, unlike the existing proposed protocols, can be adapted to any 2D structure. Its read operation is carried out on any replica of every level of the structure whereas write operations are ...

  11. A Fine-Grained Data Access Control System in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Boniface K. Alese

    2015-12-01

    Full Text Available The evolving realities of Wireless Sensor Network (WSN deployed to various terrain of life require serving multiple applications. As large amount of sensed data are distributed and stored in individual sensors nodes, the illegal access to these sensitive data can be devastating. Consequently, data insecurity becomes a big concern. This study, therefore, proposes a fine-grained access control system which only requires the right set of users to access a particular data, based on their access privileges in the sensor networks. It is designed using Priccess Protocol with Access policy formulation adopting the principle of Bell Lapadula model as well as Attribute-Based Encryption (ABE to control access to sensor data. The functionality of the proposed system is simulated using Netbeans. The performance analysis of the proposed system using execution time and size of the key show that the higher the key size, the harder it becomes for the attacker to hack the system. Additionally, the time taken for the proposed work is lesser which makes the work faster than the existing work. Consequently, a well secure interactive web-based application that could facilitates the field officers access to stored data in safe and secure manner is developed.

  12. The U.S. Culture Collection Network Responding to the Requirements of the Nagoya Protocol on Access and Benefit Sharing

    Directory of Open Access Journals (Sweden)

    Kevin McCluskey

    2017-08-01

    Full Text Available The U.S. Culture Collection Network held a meeting to share information about how culture collections are responding to the requirements of the recently enacted Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization to the Convention on Biological Diversity (CBD. The meeting included representatives of many culture collections and other biological collections, the U.S. Department of State, U.S. Department of Agriculture, Secretariat of the CBD, interested scientific societies, and collection groups, including Scientific Collections International and the Global Genome Biodiversity Network. The participants learned about the policies of the United States and other countries regarding access to genetic resources, the definition of genetic resources, and the status of historical materials and genetic sequence information. Key topics included what constitutes access and how the CBD Access and Benefit-Sharing Clearing-House can help guide researchers through the process of obtaining Prior Informed Consent on Mutually Agreed Terms. U.S. scientists and their international collaborators are required to follow the regulations of other countries when working with microbes originally isolated outside the United States, and the local regulations required by the Nagoya Protocol vary by the country of origin of the genetic resource. Managers of diverse living collections in the United States described their holdings and their efforts to provide access to genetic resources. This meeting laid the foundation for cooperation in establishing a set of standard operating procedures for U.S. and international culture collections in response to the Nagoya Protocol.

  13. Permission to Speak: A Novel Formal Foundation for Access Control

    Science.gov (United States)

    2016-06-21

    Permission to Speak: A Novel Formal Foundation for Access Control Oleg Sokolsky Nikhil Dinesh, Insup Lee, Aravind Joshi Report Documentation Page...comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE 04 NOV 2009 2. REPORT TYPE 3...DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Permission to Speak: A Novel Formal Foundation for Access Control 5a. CONTRACT

  14. A Power-Efficient Access Point Operation for Infrastructure Basic Service Set in IEEE 802.11 MAC Protocol

    Directory of Open Access Journals (Sweden)

    Hua Ye Ming

    2006-01-01

    Full Text Available Infrastructure-based wireless LAN technology has been widely used in today's personal communication environment. Power efficiency and battery management have been the center of attention in the design of handheld devices with wireless LAN capability. In this paper, a hybrid protocol named improved PCF operation is proposed, which intelligently chooses the access point- (AP- assisted DCF (distributed coordinator function and enhanced PCF (point coordinator function transmission mechanism of IEEE 802.11 protocol in an infrastructure-based wireless LAN environment. Received signal strength indicator (RSSI is used to determine the tradeoff between direct mobile-to-mobile transmission and transmission routed by AP. Based on the estimation, mobile stations can efficiently communicate directly instead of being routed through AP if they are in the vicinity of each other. Furthermore, a smart AP protocol is proposed as extension to the improved PCF operation by utilizing the historical end-to-end delay information to decide the waking up time of mobile stations. Simulation results show that using the proposed protocol, energy consumption of mobile devices can be reduced at the cost of slightly longer end-to-end packet delay compared to traditional IEEE 802.11 PCF protocol. However, in a non-time-critical environment, this option can significantly prolong the operation time of mobile devices.

  15. An Extended Role Based Access Control Method for XML Documents

    Institute of Scientific and Technical Information of China (English)

    MENG Xiao-feng; LUO Dao-feng; OU Jian-bo

    2004-01-01

    As XML has been increasingly important as the Data-change format of Internet and Intranet, access-control-on-XML-properties rises as a new issue.Role-based access control (RBAC) is an access control method that has been widely used in Internet, Operation System and Relation Data Base these 10 years.Though RBAC is already relatively mature in the above fields, new problems occur when it is used in XML properties.This paper proposes an integrated model to resolve these problems, after the fully analysis on the features of XML and RBAC.

  16. A new access control system by fingerprint for radioisotope facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Hiroko; Hirata, Yasuki [Kyushu Univ., Fukuoka (Japan). Radioisotope Center; Kondo, Takahiro; Takatsuki, Katsuhiro

    1998-04-01

    We applied a new fingerprint checker for complete access control to the radiation controlled area and to the radioisotope storage room, and prepared softwares for the best use of this checker. This system consists of a personal computer, access controllers, a fingerprint register, fingerprint checkers, a tenkey and mat sensors, permits ten thousand users to register their fingerprints and its hard disk to keep more than a million records of user`s access. Only 1% of users could not register their fingerprints worn-out, registered four numbers for a fingerprint. The softwares automatically provide varieties of reports, caused a large reduction in manual works. (author)

  17. Access control management for e-Healthcare in cloud environment

    Directory of Open Access Journals (Sweden)

    Lili Sun

    2014-03-01

    Full Text Available Data outsourcing is a major component for cloud computing that allows data owners to distribute resources to external services for users and organizations who can apply the resources. A crucial problem for owners is how to make sure their sensitive information accessed by legitimate users only using the trusted services but not authorized to read the actual information. With the increased development of cloud computing, it brings challenges for data security and access control when outsourcing users’ data and sharing sensitive data in cloud environment since it is not within the same trusted domain as data owners’. Access control policies have become an important issue in the security filed in cloud computing. Semantic web technologies represent much richer forms of relationships among users, resources and actions among different web applications such as clouding computing. However, Semantic web applications pose new requirements for security mechanisms especially in the access control models. This paper addresses existing access control methods and presents a semantic based access control model which considers semantic relations among different entities in cloud computing environment. We have enriched the research for semantic web technology with role-based access control that is able to be applied in the field of medical information system or e-Healthcare system. This work shows how the semantic web technology provides efficient solutions for the management of complex and distributed data in heterogeneous systems, and it can be used in the medical information systems as well.

  18. Urban Studies: A Study of Bibliographic Access and Control.

    Science.gov (United States)

    Anderson, Barbara E.

    This paper analyzes: (1) the bibliographic access to publications in urban studies via printed secondary sources; (2) development and scope of classification systems and of vocabulary control for urban studies; and (3) currently accessible automated collections of bibliographic citations. Urban studies is defined as "an agglomeration of…

  19. Geospacial information utilized under the access control strategy

    Institute of Scientific and Technical Information of China (English)

    TIAN Jie; ZHANG Xin-fang; WANG Tong-yang; XIANG Wei; Cheng Ming

    2007-01-01

    This paper introduces a solution to the secure requirement for digital rights management (DRM) by the way of geospacial access control named geospacial access control (GeoAC) in geospacial field. The issues of authorization for geospacial DRM are concentrated on. To geospacial DRM, one aspect is the declaration and enforcement of access rights, based on geographic aspects. To the approbation of digital geographic content, it is important to adopt online access to geodata through a spacial data infrastructure (SDI). This results in the interoperability requirements on three different levels: data model level, service level and access control level. The interaction between the data model and service level can be obtained by criterions of the open geospacial consortium (OGC), and the interaction of the access control level may be reached by declaring and enforcing access restrictions in GeoAC. Then an archetype enforcement based on GeoAC is elucidated. As one aspect of performing usage rights, the execution of access restrictions as an extension to a regular SDI is illuminated.

  20. PANATIKI: a network access control implementation based on PANA for IoT devices.

    Science.gov (United States)

    Moreno Sanchez, Pedro; Marin Lopez, Rafa; Gomez Skarmeta, Antonio F

    2013-11-01

    Internet of Things (IoT) networks are the pillar of recent novel scenarios, such as smart cities or e-healthcare applications. Among other challenges, these networks cover the deployment and interaction of small devices with constrained capabilities and Internet protocol (IP)-based networking connectivity. These constrained devices usually require connection to the Internet to exchange information (e.g., management or sensing data) or access network services. However, only authenticated and authorized devices can, in general, establish this connection. The so-called authentication, authorization and accounting (AAA) services are in charge of performing these tasks on the Internet. Thus, it is necessary to deploy protocols that allow constrained devices to verify their credentials against AAA infrastructures. The Protocol for Carrying Authentication for Network Access (PANA) has been standardized by the Internet engineering task force (IETF) to carry the Extensible Authentication Protocol (EAP), which provides flexible authentication upon the presence of AAA. To the best of our knowledge, this paper is the first deep study of the feasibility of EAP/PANA for network access control in constrained devices. We provide light-weight versions and implementations of these protocols to fit them into constrained devices. These versions have been designed to reduce the impact in standard specifications. The goal of this work is two-fold: (1) to demonstrate the feasibility of EAP/PANA in IoT devices; (2) to provide the scientific community with the first light-weight interoperable implementation of EAP/PANA for constrained devices in the Contiki operating system (Contiki OS), called PANATIKI. The paper also shows a testbed, simulations and experimental results obtained from real and simulated constrained devices.

  1. Access Control of Web- and Java-Based Applications

    Science.gov (United States)

    Tso, Kam S.; Pajevski, Michael J.

    2013-01-01

    Cybersecurity has become a great concern as threats of service interruption, unauthorized access, stealing and altering of information, and spreading of viruses have become more prevalent and serious. Application layer access control of applications is a critical component in the overall security solution that also includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. An access control solution, based on an open-source access manager augmented with custom software components, was developed to provide protection to both Web-based and Javabased client and server applications. The DISA Security Service (DISA-SS) provides common access control capabilities for AMMOS software applications through a set of application programming interfaces (APIs) and network- accessible security services for authentication, single sign-on, authorization checking, and authorization policy management. The OpenAM access management technology designed for Web applications can be extended to meet the needs of Java thick clients and stand alone servers that are commonly used in the JPL AMMOS environment. The DISA-SS reusable components have greatly reduced the effort for each AMMOS subsystem to develop its own access control strategy. The novelty of this work is that it leverages an open-source access management product that was designed for Webbased applications to provide access control for Java thick clients and Java standalone servers. Thick clients and standalone servers are still commonly used in businesses and government, especially for applications that require rich graphical user interfaces and high-performance visualization that cannot be met by thin clients running on Web browsers

  2. Modeling Access Control Policy of a Social Network

    Directory of Open Access Journals (Sweden)

    Chaimaa Belbergui

    2016-06-01

    Full Text Available Social networks bring together users in a virtual platform and offer them the ability to share -within the Community- personal and professional information’s, photos, etc. which are sometimes sensitive. Although, the majority of these networks provide access control mechanisms to their users (to manage who accesses to which information, privacy settings are limited and do not respond to all users' needs. Hence, the published information remain all vulnerable to illegal access. In this paper, the access control policy of the social network "Facebook" is analyzed in a profound way by starting with its modeling with "Organization Role Based Access Control" model, and moving to the simulation of the policy with an appropriate simulator to test the coherence aspect, and ending with a discussion of analysis results which shows the gap between access control management options offered by Facebook and the real requirements of users in the same context. Extracted conclusions prove the need of developing a new access control model that meets most of these requirements, which will be the subject of a forthcoming work.

  3. State of the Art Authentication, Access Control, and Secure Integration in Smart Grid

    Directory of Open Access Journals (Sweden)

    Neetesh Saxena

    2015-10-01

    Full Text Available The smart grid (SG is a promising platform for providing more reliable, efficient, and cost effective electricity to the consumers in a secure manner. Numerous initiatives across the globe are taken by both industry and academia in order to compile various security issues in the smart grid network. Unfortunately, there is no impactful survey paper available in the literature on authentications in the smart grid network. Therefore, this paper addresses the required objectives of an authentication protocol in the smart grid network along with the focus on mutual authentication, access control, and secure integration among different SG components. We review the existing authentication protocols, and analyze mutual authentication, privacy, trust, integrity, and confidentiality of communicating information in the smart grid network. We review authentications between the communicated entities in the smart grid, such as smart appliance, smart meter, energy provider, control center (CC, and home/building/neighborhood area network gateways (GW. We also review the existing authentication schemes for the vehicle-to-grid (V2G communication network along with various available secure integration and access control schemes. We also discuss the importance of the mutual authentication among SG entities while providing confidentiality and privacy preservation, seamless integration, and required access control with lower overhead, cost, and delay. This paper will help to provide a better understanding of current authentication, authorization, and secure integration issues in the smart grid network and directions to create interest among researchers to further explore these promising areas.

  4. Personnel Access Control System Evaluation for National Ignition Facility Operations

    Energy Technology Data Exchange (ETDEWEB)

    Altenbach, T; Brereton, S.; Hermes, G.; Singh, M.

    2001-06-01

    The purpose of this document is to analyze the baseline Access Control System for the National Ignition Facility (NIF), and to assess its effectiveness at controlling access to hazardous locations during full NIF operations. It reviews the various hazards present during a NIF shot sequence, and evaluates the effectiveness of the applicable set of controls at preventing access while the hazards are present. It considers only those hazards that could potentially be lethal. In addition, various types of technologies that might be applicable at NIF are reviewed, as are systems currently in use at other facilities requiring access control for safety reasons. Recommendations on how this system might be modified to reduce risk are made.

  5. CANbus protocol and applications for STAR TOF Control

    Science.gov (United States)

    Schambach, J.; Bridges, L.; Burton, W.; Eppley, G.; Kajimoto, K.; Nussbaum, T.

    2011-12-01

    A large-area Time-of-Flight (TOF) system based on Multi-gap Resistive Plate Chambers (MRPCs) has recently been installed in the STAR experiment at RHIC. The approximately 23000 detector channels are read out and digitized using custom electronics based on the CERN NINO and HPTDC chips. The data are sent to the experimental data acquisition system (DAQ) using the ALICE fiber optics based Detector Data Link (DDL). The readout system consists of a total of approximately 2100 custom electronics boards mounted directly on 120 TOF trays, as well as four DAQ and trigger interface boards outside the detector that collect data from 30 trays each and send it to DAQ. Control and monitoring of these electronics boards is done using a tiered network of CANbus connections to a control PC. We describe the physical implementation and topology of the CANbus connections and the custom protocol developed for this project. Several command-line tools as well as a Qt4-based graphical tool developed on the host side to facilitate configuration, control, and monitoring of the TOF system are also described.

  6. Experience with ActiveX control for simple channel access

    Energy Technology Data Exchange (ETDEWEB)

    Timossi, C.; Nishimura, H.; McDonald, J.

    2003-05-15

    Accelerator control system applications at Berkeley Lab's Advanced Light Source (ALS) are typically deployed on operator consoles running Microsoft Windows 2000 and utilize EPICS[2]channel access for data access. In an effort to accommodate the wide variety of Windows based development tools and developers with little experience in network programming, ActiveX controls have been deployed on the operator stations. Use of ActiveX controls for use in the accelerator control environment has been presented previously[1]. Here we report on some of our experiences with the use and development of these controls.

  7. Enhancing Data Security and Access Control in Cloud Environment using Modified Attribute Based Encryption Mechanism

    Directory of Open Access Journals (Sweden)

    Apurva R. Naik

    2016-10-01

    Full Text Available Social networking and growing popularity of cloud services have made everyone to communicate each other in an easiest way. File sharing and distribution are the frequently used services provided by cloud service providers, although these facilities reduce cost of data sharing but at the same time data security and access control is the major problem. Many renowned service providers have faced the challenges to secure data and provide better access control, and we know once the data is leaked we cannot recover the data loss. Thus in order to ensure better security we need for focus on the two major problems, and those are access control and encryption policy. Cipher text policy attribute based encryption is the most effective solution for access control in real time scenarios where owner can actually decide the access rights for the end-user, but it comes with key escrow problem. We are proposing our modified escrow-free key issuing protocol to solve the problem of key escrow and our Modified Attribute Based Encryption scheme to achieve all security requirements to get a robust and secure system. Further we evaluate our model on the basis of results and lastly we conclude the paper.

  8. Testing Efficiency Improved by Addition of Remote Access Control Room

    Science.gov (United States)

    1996-01-01

    The NASA Lewis Research Center's Remote Access Control Room (RACR) uses off-the-shelf video conferencing software integrated with existing facility data systems to provide access to the test data by networking from virtually anywhere in the country. The system allows research engineers in remote locations to participate in tests and monitor data in real time just as if they were present in the control room.

  9. Ensuring quality of service for multimedia services in two-step reservation MAC protocol for PLC access networks

    Science.gov (United States)

    Hrasnica, Halid; Lehnert, Ralf

    2004-09-01

    Recent and future communications networks have to provide QoS guarantees for a rapidly growing number of various telecommunication services, which can be ensured by application of an efficient MAC layer. Various communication technologies, such as cellular networks and PLC (PowerLine Communications) access networks, apply reservation MAC protocols, providing a good network utilization and realization of different QoS guarantees. In this investigation, we analyze possibilities for provision of QoS guarantees for various telecommunications services with a two-step reservation MAC protocol using per-packet reservation principle, which is proposed for application in broadband PLC access networks. Particularly, performance of the reservation procedure is analyzed to provide priority mechanisms which are necessary for realization of various telecommunications services ensuring the required QoS guarantees. Since the telephony, realized by the packet voice service, has the strongest QoS requirements among various telecommunications services, we analyze possibility for its realization within the two-step MAC protocol. It can be concluded that the packet voice can be efficiently implemented. However, with application of a combined reservation domains for various service classes, network performance could be further improved.

  10. Dynamically Authorized Role-Based Access Control for Grid Applications

    Institute of Scientific and Technical Information of China (English)

    YAO Hanbing; HU Heping; LU Zhengding; LI Ruixuan

    2006-01-01

    Grid computing is concerned with the sharing and coordinated use of diverse resources in distributed "virtual organizations". The heterogeneous, dynamic and multi-domain nature of these environments makes challenging security issues that demand new technical approaches. Despite the recent advances in access control approaches applicable to Grid computing, there remain issues that impede the development of effective access control models for Grid applications. Among them there are the lack of context-based models for access control, and reliance on identity or capability-based access control schemes. An access control scheme that resolve these issues is presented, and a dynamically authorized role-based access control (D-RBAC) model extending the RBAC with context constraints is proposed. The D-RABC mechanisms dynamically grant permissions to users based on a set of contextual information collected from the system and user's environments, while retaining the advantages of RBAC model. The implementation architecture of D-RBAC for the Grid application is also described.

  11. A mobile console for local access to accelerator control systems.

    CERN Multimedia

    1981-01-01

    Microprocessors were installed as auxiliary crate controllers (ACCs) in the CAMAC interface of control systems for various accelerators. The same ACC was also at the hearth of a stand-alone system in the form of a mobile console. This was also used for local access to the control systems for tests and development work (Annual Report 1981, p. 80, Fig. 10).

  12. Remote device access in the new accelerator controls middleware

    CERN Document Server

    Baggiolini, V; Jensen, S; Kostro, K; Risso, A; Trofimov, N N; SL

    2001-01-01

    This paper presents the Remote Device Access (RDA) package developed at CERN in the framework of the joint PS/SL Controls Middleware project. The package design reflects the Accelerator Device Model in which devices, named entities in the control system, can be controlled via properties. RDA implements this model in a distributed environment with devices residing in servers that can run anywhere in the controls network. It provides a location-independent and reliable access to the devices from control programs. By invoking the device access methods, clients can read, write and subscribe to device property values. We describe the architecture and design of RDA its API, and CORBA-based implementations in Java and C++. First applications of RDA in the CERN accelerator control systems are described as well.

  13. Security Analysis and Improvements of Authentication and Access Control in the Internet of Things

    Directory of Open Access Journals (Sweden)

    Bruce Ndibanje

    2014-08-01

    Full Text Available Internet of Things is a ubiquitous concept where physical objects are connected over the internet and are provided with unique identifiers to enable their self-identification to other devices and the ability to continuously generate data and transmit it over a network. Hence, the security of the network, data and sensor devices is a paramount concern in the IoT network as it grows very fast in terms of exchanged data and interconnected sensor nodes. This paper analyses the authentication and access control method using in the Internet of Things presented by Jing et al. According to our analysis, Jing et al.’s protocol is costly in the message exchange and the security assessment is not strong enough for such a protocol. Therefore, we propose improvements to the protocol to fill the discovered weakness gaps. The protocol enhancements facilitate many services to the users such as user anonymity, mutual authentication, and secure session key establishment. Finally, the performance and security analysis show that the improved protocol possesses many advantages against popular attacks, and achieves better efficiency at low communication cost.

  14. Optimal Medium Access Control in Cognitive Radios: A Sequential Design Approach

    CERN Document Server

    Lai, Lifeng; Jiang, Hai; Poor, H Vincent

    2008-01-01

    The design of medium access control protocols for a cognitive user wishing to opportunistically exploit frequency bands within parts of the radio spectrum having multiple bands is considered. In the scenario under consideration, the availability probability of each channel is unknown a priori to the cognitive user. Hence efficient medium access strategies must strike a balance between exploring the availability of channels and exploiting the opportunities identified thus far. Using a sequential design approach, an optimal medium access strategy is derived. To avoid the prohibitive computational complexity of this optimal strategy, a low complexity asymptotically optimal strategy is also developed. The proposed strategy does not require any prior statistical knowledge about the traffic pattern on the different channels.

  15. The Economics of Information, Studiously Ignored in the Nagoya Protocol on Access to Genetic Resources and Benefit Sharing

    Directory of Open Access Journals (Sweden)

    Joseph Henry Vogel et. al.

    2011-06-01

    Full Text Available The economics of information has been studiously ignored in the ten Conferences of the Parties to the Convention on Biological Diversity. Nevertheless, an academic literature exists which recognises genetic resources and associated traditional knowledge as natural and artificial information. Its unambiguous prescriptions would widen the scope of the Nagoya Protocol on Access to Genetic Resources and Benefit Sharing (ABS and resolve almost all of the contentious issues identified by Kamau et al. One begins with retroactivity: because biological resources exhibit tangible and intangible aspects, the latter can be conceptualised as a set of natural information where value currently added in a patent is access to a subset not previously accessed. The economics quickly leads to a justification for a biodiversity cartel among countries of origin, wholly analogous to monopoly intellectual property rights. To achieve such a sea change in policymaking, the justification must be accompanied by a narrative that can penetrate the social sphere, much as Trade Related Intellectual Property Rights achieved through the World Intellectual Property Organisation. Several examples of bio-discoveries drawn from a popular medium are analysed in terms of the contentious issues of the Protocol and the distinct ABS that would eventuate under cartelisation. History also offers an analogy. The Parties’ eighteen years of resistance (1993-2011 to applying the economics of information to genetic resources is reminiscent to the twenty-seven years that the British Parliament rebuffed David Ricardo’s economic analysis of the Corn Laws (1815-1842.

  16. Design and Implementation of Embedded Transmission Control Protocol/Internet Protocol Network Based on System-on-programmable Chip

    Institute of Scientific and Technical Information of China (English)

    LUO Yong; HAN Xiao-jun

    2008-01-01

    A scheme of transmission control protocol/Internet protocol(TCP/IP) network system based on system-on-programmable chip(SOPC) is proposed for the embedded network communication. In this system, Nios processor, Ethernet controller and other peripheral logic circuits are all integrated on a Stratix Ⅱ field programmable gate array(FPGA) chip by using SOPC builder design software. And the network communication is realized by transplanting MicroC/OS Ⅱ(μC/OS Ⅱ) operation system and light weight Internet protocol(LwIP). The design idea, key points and the structures of both software and hardware of the system are presented and ran with a telecommunication example. The experiment shows that the embedded TCP/IP network system has high reliability and real-time performance.

  17. Improving accessibility of trust guidelines and protocols at the Great Western Hospital, Swindon.

    Science.gov (United States)

    Robertson, Ian; Smith, Abigail; Tucker, Jennifer; Cilia, Erica; Chen, Kangni; Marion, Rose; Nesbitt, Julian; Ramcharitar, Steve; Cathiavadi Greamspet, Mala

    2014-01-01

    Trust guidelines and policies outline recommendations for the management of common clinical and non-clinical situations, serving to standardise best practice. Prior to this project, there was no consolidated location for these documents. Lack of organisational structure and inadequate search functionality within the trust intranet led to time wasted locating information, acting outside of recognised best practice, and ultimately potentially compromising patient safety. We surveyed 55 junior doctors, 95% of respondents were dependent on guidelines on a daily basis. 20% spending greater than 5 minutes to locate protocols and 38% unable to locate some relevant documents at all. We analysed the time taken for junior doctors to locate six randomly selected protocols. Pre-intervention mean time was 133 seconds (on six occasions doctors were unable to locate the guideline). All trust guidelines and protocols currently available on the intranet were collated, consolidated, and renamed according to content. These were then re-alphabetised and new search terms linked to each document. Existing links were then uploaded and a single web page made available via the trust intranet homepage. The new page was publicised by email, posters and interdepartmental presentations. In our post intervention survey, 97% of respondents were aware of the project and had made use of the page. All protocols were located during re-testing with 90% of those resurveyed stating it was easier to locate protocols. Overall, a reduction in the time and number of clicks required to locate protocols was demonstrated: mean time 16 seconds vs 133 seconds pre-intervention (n=60). 53% of guidelines located in <30s and 86% <2 minutes.

  18. Secure Remote Access Issues in a Control Center Environment

    Science.gov (United States)

    Pitts, Lee; McNair, Ann R. (Technical Monitor)

    2002-01-01

    The ISS finally reached an operational state and exists for local and remote users. Onboard payload systems are managed by the Huntsville Operations Support Center (HOSC). Users access HOSC systems by internet protocols in support of daily operations, preflight simulation, and test. In support of this diverse user community, a modem security architecture has been implemented. The architecture has evolved over time from an isolated but open system to a system which supports local and remote access to the ISS over broad geographic regions. This has been accomplished through the use of an evolved security strategy, PKI, and custom design. Through this paper, descriptions of the migration process and the lessons learned are presented. This will include product decision criteria, rationale, and the use of commodity products in the end architecture. This paper will also stress the need for interoperability of various products and the effects of seemingly insignificant details.

  19. Access to finance for community forest management under the UNFCCC and Kyoto Protocol

    NARCIS (Netherlands)

    Skutsch, Margaret

    2002-01-01

    A previous article in ETFRN News reviewed the potential for funding for forestry under international climate agreements, particularly under the Kyoto Protocol (Skutsch, 2000). Since then, further negotiations have taken place and this article aims at giving an overview of the current situation.

  20. CSchema: A Downgrading Policy Language for XML Access Control

    Institute of Scientific and Technical Information of China (English)

    Dong-Xi Liu

    2007-01-01

    The problem of regulating access to XML documents has attracted much attention from both academic and industry communities.In existing approaches, the XML elements specified by access policies are either accessible or inac-cessible according to their sensitivity.However, in some cases, the original XML elements are sensitive and inaccessible, but after being processed in some appropriate ways, the results become insensitive and thus accessible.This paper proposes a policy language to accommodate such cases, which can express the downgrading operations on sensitive data in XML documents through explicit calculations on them.The proposed policy language is called calculation-embedded schema (CSchema), which extends the ordinary schema languages with protection type for protecting sensitive data and specifying downgrading operations.CSchema language has a type system to guarantee the type correctness of the embedded calcula-tion expressions and moreover this type system also generates a security view after type checking a CSchema policy.Access policies specified by CSchema are enforced by a validation procedure, which produces the released documents containing only the accessible data by validating the protected documents against CSchema policies.These released documents are then ready tobe accessed by, for instance, XML query engines.By incorporating this validation procedure, other XML processing technologies can use CSchema as the access control module.

  1. Distributed Medium Access Control with SDMA Support for WLANs

    Science.gov (United States)

    Zhou, Sheng; Niu, Zhisheng

    With simultaneous multi-user transmissions, spatial division multiple access (SDMA) provides substantial throughput gain over the single user transmission. However, its implementation in WLANs with contention-based IEEE 802.11 MAC remains challenging. Problems such as coordinating and synchronizing the multiple users need to be solved in a distributed way. In this paper, we propose a distributed MAC protocol for WLANs with SDMA support. A dual-mode CTS responding mechanism is designed to accomplish the channel estimation and user synchronization required for SDMA. We analytically study the throughput performance of the proposed MAC, and dynamic parameter adjustment is designed to enhance the protocol efficiency. In addition, the proposed MAC protocol does not rely on specific physical layer realizations, and can work on legacy IEEE 802.11 equipment with slight software updates. Simulation results show that the proposed MAC outperforms IEEE 802.11 significantly, and that the dynamic parameter adjustment can effectively track the load variation in the network.

  2. A MODEL FOR CONGESTION CONTROL OF TRANSMISSION CONTROL PROTOCOL IN MOBILE WIRELESS AD HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    Adib M. Monzer Habbal

    2013-01-01

    Full Text Available Transmission Control Protocol (TCP is a fundamental protocol in the TCP/IP Protocol Suite.TCP was well designed and optimized to work over wired networks where most packet loss occurs due to network congestion. In theory, TCP should not care whether it is running over wired networks, WLANs, or Mobile Ad hoc Networks (MANETs. In practice, it does matter because most TCP deployments have been carefully designed based on the assumption that congestion is the main factor of network instability. However, MANETs have other dominating factors that cause network instability. Forgetting the impact of these factors violates some design principles of TCP congestion control and open questions for future research to address. This study aims to introduce a model that shows the impact of MANET factors on TCP congestion control. To achieve this aim, Design Research Methodology (DRM proposed by BLESSING was used as a guide to present this model. The proposed model describes the existing situation of TCP congestion control. Furthermore, it points to the factors that are most suitable to be addressed by researchers in order to improve TCP performance. This research proposes a novel model to present the impact of MANET factors on TCP congestion control. The model is expected to serve as a benchmark for any intended improvement and enhancement of TCP congestion control over MANET.

  3. Implementing context and team based access control in healthcare intranets.

    Science.gov (United States)

    Georgiadis, Christos K; Mavridis, Ioannis K; Nikolakopoulou, Georgia; Pangalos, George I

    2002-09-01

    The establishment of an efficient access control system in healthcare intranets is a critical security issue directly related to the protection of patients' privacy. Our C-TMAC (Context and Team-based Access Control) model is an active security access control model that layers dynamic access control concepts on top of RBAC (Role-based) and TMAC (Team-based) access control models. It also extends them in the sense that contextual information concerning collaborative activities is associated with teams of users and user permissions are dynamically filtered during runtime. These features of C-TMAC meet the specific security requirements of healthcare applications. In this paper, an experimental implementation of the C-TMAC model is described. More specifically, we present the operational architecture of the system that is used to implement C-TMAC security components in a healthcare intranet. Based on the technological platform of an Oracle Data Base Management System and Application Server, the application logic is coded with stored PL/SQL procedures that include Dynamic SQL routines for runtime value binding purposes. The resulting active security system adapts to current need-to-know requirements of users during runtime and provides fine-grained permission granularity. Apart from identity certificates for authentication, it uses attribute certificates for communicating critical security metadata, such as role membership and team participation of users.

  4. A RAMP CODE FOR FINE-GRAINED ACCESS CONTROL

    Directory of Open Access Journals (Sweden)

    Kannan Karthik

    2013-02-01

    Full Text Available Threshold ramp secret sharing schemes are designed so that (i certain subsets of shares have no information about the secret, (ii some subsets have partial information about the secret and (iii some subsets have complete information to recover the secret. However most of the ramp schemes in present literature do not control the leakage of information in partial access sets, due to which the information acquired by these sets is devoid of structure and not useful for fine-grained access control. Through a non-perfect secret sharing scheme called MIX-SPLIT, an encoding methodology for controlling the leakage in partial access sets is proposed and this is used for fine-grained access to binary strings. The ramp code generated using MIX-SPLIT requires a much smaller share size of O(n, as compared to Shamir's ramp adaptation which incurs a share size of atleast O(n2 for the same multi-access structure. The proposed ramp code is finally applied towards the protection and fine-grained access of industrial design drawings.

  5. Identity Authentication and Capability Based Access Control (IACAC) for the Internet of Things

    DEFF Research Database (Denmark)

    Mahalle, Parikshit N.; Anggorojati, Bayu; Prasad, Neeli R.

    2013-01-01

    and weak physical security of low power devices in IoT networks are possible sources for security vulnerabilities. It is promising to make an authentication and access control attack resistant and lightweight in a resource constrained and distributed IoT environment. This paper presents the Identity...... is secure against aforementioned attacks. This paper also discusses performance analysis of the protocol in terms of computational time compared to other existing solutions. Furthermore, this paper addresses challenges in IoT and security attacks are modelled with the use cases to give an actual view of IoT......In the last few years the Internet of Things (IoT) has seen widespread application and can be found in each field. Authentication and access control are important and critical functionalities in the context of IoT to enable secure communication between devices. Mobility, dynamic network topology...

  6. C-LOAD POWER CONTROL PROTOCOL-CROSS-LAYER DESIGN OF A NETWORK LAYER LOAD POWER CONTROL PROTOCOL IN WIRELESS AD HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    A. Arivoli

    2014-01-01

    Full Text Available In wireless ad hoc network scenario, Cross-layer design is emerging, important in wireless ad hoc network and the power control methods. Power control is the intelligent selection of transmit power in a communication to achieve the better performance within the system. Cross-layer is used to sharing the information between the layers. Physical to Transport layer information are shared in this protocol, due to this cross-layering is designed to optimize the power control. CLD using LOADPOWER (LOADPOW control protocol is reduce the overall end-end delay and the energy consumption using transmission power. The novelty of this work deals with both low and high transmission power control methodologies. So many power control schemes are dealt in MAC layer but this work, Power control protocol was done in network layer and it plays a vital role. A MAC approach to power control only does a local optimization whereas network layer is capable of global optimization. Simulation was done in NS-2 simulator with the performance metrics as improved throughput, energy consumption and end-end delay. The key concept is to improve the throughput, saves energy by sending all the packets with optimal transmission power according to the network load. A comparison of few protocols with Load Power Control Protocol (LPCP was implemented and got the better performances using NS-2 simulator.

  7. Analysis of Multi-Channel and Slotted Random Multi-Access Protocol with Two-Dimensional Probability for Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ningyu; ZHAO Dongfeng; DING Hongwei

    2008-01-01

    A higher quality of service (QoS) is provided for ad hoc networks through a multi-channel and slotted random multi-access (MSRM) protocol with two-dimensional probability. For this protocol, the system time is slotted into a time slot with high channel utilization realized by the choice of two parameters p1 and p2, and the channel load equilibrium. The protocol analyzes the throughput of the MSRM protocol for a load equilibrium state and the throughput based on priority. Simulations agree with the theoretical analysis. The simulations also show that the slotted-time system is better than the continuous-time system.

  8. Delay analysis of an integrated voice and data access protocol with collision detection for multimedia satellite networks

    Science.gov (United States)

    Poon, Charles C. K.; Suda, Tatsuya

    1992-03-01

    The novel multiple-access scheme for multimedia satellite networks presented is based on a combination of FDMA and TDMA, integrating both circuit and packet-switching techniques. While the circuit-switching method is used to transmit such stream-type traffic as real-time voice communications, packet-switching is used to transmit such 'bursty' traffic as interactive data. A ground radio network is assumed for control signaling; the tone sense multiple access/partial collision detection scheme is implemented on this network to enhance the integrated access scheme's performance.

  9. Modified Distributed Medium Access Control Algorithm Based on Multi-Packets Reception in Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    ZHENG Qing; YANG Zhen

    2005-01-01

    Based on the Multi-Packet Reception(MPR)capability at the physical layer and the Distributed Coordination Function(DCF)of the IEEE 802.11 MAC protocol,we propose a modified new solution about WAITING mechanism to make full use of the MPR capability in this paper,which is named as modified distributed medium access control algorithm.We describe the details of each step of the algorithm after introducing the WAITING mechanism.Then,we also analyze how the waiting-time affects the throughput performance of the network.The network simulator NS-2 is used to evaluate the throughput performance of the new WAITING algorithm and we compare it with IEEE 802.11 MAC protocol and the old WAITING algorithm.The experimental results show that our new algorithm has the best performance.

  10. Session Types for Access and Information Flow Control

    OpenAIRE

    Capecchi, Sara; Castellani, Ilaria; Dezani-Ciancaglini, Mariangiola; Rezk, Tamara

    2010-01-01

    We consider a calculus for multiparty sessions with delegation, enriched with security levels for session participants and data. We propose a type system that guarantees both session safety and a form of access control. Moreover, this type system ensures secure information flow, including controlled forms of declassification. In particular, it prevents leaks due to the specific control constructs of the calculus, such as session opening, selection, branching and delegation. We illustrate the ...

  11. Controlling user access to electronic resources without password

    Science.gov (United States)

    Smith, Fred Hewitt

    2015-06-16

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes pre-determining an association of the restricted computer resource and computer-resource-proximal environmental information. Indicia of user-proximal environmental information are received from a user requesting access to the restricted computer resource. Received indicia of user-proximal environmental information are compared to associated computer-resource-proximal environmental information. User access to the restricted computer resource is selectively granted responsive to a favorable comparison in which the user-proximal environmental information is sufficiently similar to the computer-resource proximal environmental information. In at least some embodiments, the process further includes comparing user-supplied biometric measure and comparing it with a predetermined association of at least one biometric measure of an authorized user. Access to the restricted computer resource is granted in response to a favorable comparison.

  12. Privacy Preservation in Role-based Access Control Model

    Directory of Open Access Journals (Sweden)

    Zuo Chen

    2011-08-01

    Full Text Available Privacy preservation is a crucial problem in resource sharing and collaborating among multi-domains. Based on this problem, we propose a role-based access control model for privacy preservation. This scheme avoided the privacy leakage of resources while implementing access control, and it has the advantage of lower communication overhead. We demonstrate this scheme meets the IND-CCA2 semantic security by using random oracle. The simulation result shows this scheme has better execution efficiency and application effects.

  13. Improvement The Transmission Efficiency For Wireless Packet Communication Systems Using Automatic Control for power And Time Slot Width Of Slotted Non persistent ISMA Protocol

    Directory of Open Access Journals (Sweden)

    Saad M. Hardan

    2013-05-01

    Full Text Available In packed communication systems which use a protocol, the protocol should perform the allocation of channels such that the transmission channel is used efficiently. Efficiency is usually measured in terms of channel throughput and the average transmission  delay. The Slotted Nonpersistent ISMA protocol is one of random access protocols used in packed communication systems. In this research a Slotted Nonpersistent ISMA protocol Model with automatic control for power and time slot is proposed. the suggested algorithm enable the base station(access point to control  the protocol time slot length and  transmission power in a dynamic way to control the normalized propagation delay d and to maintain all the uplink signals in the limit of captured power threshold (capture ratio in order to control the  throughput and the average transmission delay of the communication system by an automatic method. the computer simulation results  confirm the activity of the  proposed algorithm for increasing the  throughput and decreasing the average transmission delay by an accepted ratios.

  14. Code-expanded radio access protocol for machine-to-machine communications

    DEFF Research Database (Denmark)

    Thomsen, Henning; Kiilerich Pratas, Nuno; Stefanovic, Cedomir

    2013-01-01

    The random access methods used for support of machine-to-machine, also referred to as Machine-Type Communications, in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. We propose an approach that is motivated b...

  15. Multiple wireless protocol advertising system, enabling automatic access selection and local services

    NARCIS (Netherlands)

    Houben, S.A.; Baken, N.; Herve, P.; Smets, R.

    2006-01-01

    We examined efficiency within wireless access options for mobile devices and discovered that a classic pitfall is revisited. As with the proliferation of services in incumbents’ portfolios, leading to a number of coexisting so-called ‘stove-pipes’, we see an isomorphic phenomenon evolving in multimo

  16. Navy Commercial Access Control System Did Not Effectively Mitigate Access Control Risks

    Science.gov (United States)

    2013-09-16

    the capability to perform NCIC checks to vet contractor employees, and not all Navy installations nave the ability to access NCIC, NCACS is not...Management Corp 10,017 REA to contract N40085-06-D-1260 Goodwill Industries 199,148 Overhead charge to contract N00189-09- C-Z003 DynCorp international

  17. Database design for Physical Access Control System for nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Sathishkumar, T., E-mail: satishkumart@igcar.gov.in; Rao, G. Prabhakara, E-mail: prg@igcar.gov.in; Arumugam, P., E-mail: aarmu@igcar.gov.in

    2016-08-15

    Highlights: • Database design needs to be optimized and highly efficient for real time operation. • It requires a many-to-many mapping between Employee table and Doors table. • This mapping typically contain thousands of records and redundant data. • Proposed novel database design reduces the redundancy and provides abstraction. • This design is incorporated with the access control system developed in-house. - Abstract: A (Radio Frequency IDentification) RFID cum Biometric based two level Access Control System (ACS) was designed and developed for providing access to vital areas of nuclear facilities. The system has got both hardware [Access controller] and software components [server application, the database and the web client software]. The database design proposed, enables grouping of the employees based on the hierarchy of the organization and the grouping of the doors based on Access Zones (AZ). This design also illustrates the mapping between the Employee Groups (EG) and AZ. By following this approach in database design, a higher level view can be presented to the system administrator abstracting the inner details of the individual entities and doors. This paper describes the novel approach carried out in designing the database of the ACS.

  18. Review of Access Control Models for Cloud Computing

    Directory of Open Access Journals (Sweden)

    Natarajan Meghanathan

    2013-05-01

    Full Text Available The relationship between users and resources is dyn amic in the cloud, and service providers and users are typically not in the same security do main. Identity-based security (e.g., discretionary or mandatory access control models c annot be used in an open cloud computing environment, where each resource node may not be fa miliar, or even do not know each other. Users are normally identified by their attributes o r characteristics and not by predefined identities. There is often a need for a dynamic acc ess control mechanism to achieve cross- domain authentication. In this paper, we will focus on the following three broad categories of access control models for cloud computing: (1 Role -based models; (2 Attribute-based encryption models and (3 Multi-tenancy models. We will review the existing literature on each of the above access control models and their varian ts (technical approaches, characteristics, applicability, pros and cons, and identify future research directions for developing access control models for cloud computing environments .

  19. Testing the activitystat hypothesis: a randomised controlled trial protocol

    Directory of Open Access Journals (Sweden)

    Gomersall Sjaan

    2012-10-01

    Full Text Available Abstract Background The activitystat hypothesis proposes that when physical activity or energy expenditure is increased or decreased in one domain, there will be a compensatory change in another domain to maintain an overall, stable level of physical activity or energy expenditure. To date, there has been no experimental study primarily designed to test the activitystat hypothesis in adults. The aim of this trial is to determine the effect of two different imposed exercise loads on total daily energy expenditure and physical activity levels. Methods This study will be a randomised, multi-arm, parallel controlled trial. Insufficiently active adults (as determined by the Active Australia survey aged 18–60 years old will be recruited for this study (n=146. Participants must also satisfy the Sports Medicine Australia Pre-Exercise Screening System and must weigh less than 150 kg. Participants will be randomly assigned to one of three groups using a computer-generated allocation sequence. Participants in the Moderate exercise group will receive an additional 150 minutes of moderate to vigorous physical activity per week for six weeks, and those in the Extensive exercise group will receive an additional 300 minutes of moderate to vigorous physical activity per week for six weeks. Exercise targets will be accumulated through both group and individual exercise sessions monitored by heart rate telemetry. Control participants will not be given any instructions regarding lifestyle. The primary outcome measures are activity energy expenditure (doubly labeled water and physical activity (accelerometry. Secondary measures will include resting metabolic rate via indirect calorimetry, use of time, maximal oxygen consumption and several anthropometric and physiological measures. Outcome measures will be conducted at baseline (zero weeks, mid- and end-intervention (three and six weeks with three (12 weeks and six month (24 week follow-up. All assessors will be

  20. Regulatory Accessibility and Social Influences on State Self-Control

    OpenAIRE

    vanDellen, Michelle R.; Hoyle, Rick H.

    2009-01-01

    The current work examined how social factors influence self-control. Current conceptions of state self-control treat it largely as a function of regulatory capacity. The authors propose that state self-control might also be influenced by social factors because of regulatory accessibility. Studies 1 through 4 provide evidence that individuals’ state self-control is influenced by the trait and state self-control of salient others such that thinking of others with good trait or state self-contro...

  1. Access Control of Web and Java Based Applications

    Science.gov (United States)

    Tso, Kam S.; Pajevski, Michael J.; Johnson, Bryan

    2011-01-01

    Cyber security has gained national and international attention as a result of near continuous headlines from financial institutions, retail stores, government offices and universities reporting compromised systems and stolen data. Concerns continue to rise as threats of service interruption, and spreading of viruses become ever more prevalent and serious. Controlling access to application layer resources is a critical component in a layered security solution that includes encryption, firewalls, virtual private networks, antivirus, and intrusion detection. In this paper we discuss the development of an application-level access control solution, based on an open-source access manager augmented with custom software components, to provide protection to both Web-based and Java-based client and server applications.

  2. Accessible protocol for practice classroom about physical and chemical factors that affect the biomembranes integrity

    Directory of Open Access Journals (Sweden)

    Thiago Barros Galvão

    2012-12-01

    Full Text Available The aim of the current work is to review a protocol used in practical classes to demonstrate some factors that affect biomembrane integrity. Sugar-beet fragments were utilized as the experimental model as membrane damage could be visualized by leakage of betacyanins, hydrophilic pigments accumulated in the cell vacuoles. The tests were carried out as discrete experiments utilizing physical agents and chemical products present in the student daily routine. To test the effect of temperature, sugar-beet fragments were submitted to heat, cold or both at different times of exposition. When chemical products were tested, sugar-beet fragments were exposed to organic solvents (common alcohol and acetone or polar and amphipathic substances (disinfectant, detergent, hydrogen peroxide, and sodium hypochlorite. The obtained results were discussed in terms of the capacity of the physical and chemical factors to cause membrane damage. The review of this protocol using reagents that are present in the student daily routine were able to demonstrate clearly the effect of the different tested factors, allowing the utilization of this practical class under limited conditions.

  3. Comparison Study of Transmission Control Protocol and User Datagram Protocol Behavior over Multi-Protocol Label Switching Networks in Case of Failures

    Directory of Open Access Journals (Sweden)

    Taha A.A Radaei

    2009-01-01

    Full Text Available Problem statement: In only a few years, Multi-Protocol Label Switching (MPLS has evolved from an exotic technology to a mainstream tool used by service providers to create revenue-generating services. MPLS provides a high reliable Label Switched Path (LSP. MPLS failures may degrade the reliability of the MPLS networks. Approach: For that reason, many studies have been conducted to keep the high reliability and survivability of the MPLS networks. Unlike User Datagram Protocol (UDP, Transmission Control Protocol does not perform well in case of like-failure of MPLS networks because of its inability to distinguish packet loss due to link-failure. After the recovery time, TCP takes longer time than UDP to continue as it was before the failure. Results: In terms of packet loss, TCP performs better than UDP. However, the receiving rate of the TCP traffic is much worse than UDP traffic. A need for a mechanism to improve the behavior of TCP after a link failure is needed. This study focused on comparing the behavior of different types TCP as well as UDP traffic over MPLS networks in case of link, node or congestion failures. Conclusion: Although extensions of RSVP-TE protocol support fast recovery mechanism of MPLS networks, the behavior of TCP will be affected during recovery time much more than with UDP.

  4. Enhanced reliable transmission control protocol for spatial information networks

    Science.gov (United States)

    Qin, Zhihong; Zhang, Juan; Wang, Junfeng

    2009-12-01

    Satellites channels are generally featured by high bit error rate (BER), long propagation delay, large bandwidth-delay product (BDP) and so on. This tends to make the traditional TCP suffer from serious performance degradation in satellite networks. Therefore, a TCP-compatible reliable transmission protocol (i.e., TCP-AX) for spatial information networks is proposed in this paper. And a bandwidth probing mechanism is designed to distinguish network congestion and link error. Simulation results show that TCP-AX has better performance than some popular enhanced TCP protocols.

  5. Barriers and facilitators of access to maternal services for women with disabilities: scoping review protocol.

    Science.gov (United States)

    Mheta, Doreen; Mashamba-Thompson, Tivani P

    2017-05-16

    The Sustainable Development Goals (SDGs) emphasises the increasing equitable coverage of quality health care and provision of integrated services as means of reducing maternal mortality. Despite so much effort being placed on improved access to maternity health care, studies show that women with disabilities are being systemically excluded from the mainstream maternal health services. The proposed scoping review aims to map literature on the barriers and facilitators of access to maternal services for women with disabilities. The search strategy for this scoping review study will involve electronic databases including Pubmed, MEDLINE via EBSCOhost, CINAHL Plus with full text via EBSCOhost, Africa-Wide Info via EBSCOhost, JSTOR and Proquest Health and Medical Complete. Articles will also be searched through the "Cited by" search as well as citations included in the reference lists of included articles. A two-stage mapping strategy would be conducted. Stage 1 would be to screen studies through examining their titles. Furthermore, we will screen abstracts of the identified studies descriptively and by focus and method as stipulated by the inclusion and exclusion criteria. In stage 2, we will extract data from the included studies. A parallel screening and data extraction will be undertaken by two reviewers. We will access the quality of the included studies using the mixed methods appraisal tool (MMAT). We will use NVIVO version 10 to extract the relevant outcomes and thematic analysis of the studies. We anticipate to find relevant studies reporting evidence on the barriers and facilitators of access to maternal health services in Sub-Saharan Africa. The evidence obtained from the included studies when summarised will help guide future research. The study findings will be disseminated electronically and in print. In addition, it will be presented at conferences related to sexual reproductive health, maternal health care and reproductive health.

  6. Code-expanded radio access protocol for machine-to-machine communications

    DEFF Research Database (Denmark)

    Thomsen, Henning; Kiilerich Pratas, Nuno; Stefanovic, Cedomir

    2013-01-01

    The random access methods used for support of machine-to-machine, also referred to as Machine-Type Communications, in current cellular standards are derivatives of traditional framed slotted ALOHA and therefore do not support high user loads efficiently. We propose an approach that is motivated...... subframes and orthogonal preambles, the amount of available contention resources is drastically increased, enabling the massive support of Machine-Type Communication users that is beyond the reach of current systems....

  7. Pilot studies for the North American Soil Geochemical Landscapes Project - Site selection, sampling protocols, analytical methods, and quality control protocols

    Science.gov (United States)

    Smith, D.B.; Woodruff, L.G.; O'Leary, R. M.; Cannon, W.F.; Garrett, R.G.; Kilburn, J.E.; Goldhaber, M.B.

    2009-01-01

    In 2004, the US Geological Survey (USGS) and the Geological Survey of Canada sampled and chemically analyzed soils along two transects across Canada and the USA in preparation for a planned soil geochemical survey of North America. This effort was a pilot study to test and refine sampling protocols, analytical methods, quality control protocols, and field logistics for the continental survey. A total of 220 sample sites were selected at approximately 40-km intervals along the two transects. The ideal sampling protocol at each site called for a sample from a depth of 0-5 cm and a composite of each of the O, A, and C horizons. The acid digestion. A separate sample of 0-5-cm material was collected at each site for determination of organic compounds. A subset of 73 of these samples was analyzed for a suite of 19 organochlorine pesticides by gas chromatography. Only three of these samples had detectable pesticide concentrations. A separate sample of A-horizon soil was collected for microbial characterization by phospholipid fatty acid analysis (PLFA), soil enzyme assays, and determination of selected human and agricultural pathogens. Collection, preservation and analysis of samples for both organic compounds and microbial characterization add a great degree of complication to the sampling and preservation protocols and a significant increase to the cost for a continental-scale survey. Both these issues must be considered carefully prior to adopting these parameters as part of the soil geochemical survey of North America.

  8. Ubiquitous access control and policy management in personal networks

    DEFF Research Database (Denmark)

    Kyriazanos, Dimitris M.; Stassinopoulos, George I.; Prasad, Neeli R.

    2006-01-01

    In this paper the authors present the challenges for enabling Security Policies Management and subsequent Ubiquitous Access Control on the Personal Network (PN) environment. A solution based on Security Profiles is proposed, supporting both partially distributed architectures-having in this case...

  9. Fine-Grained Access Control for Electronic Health Record Systems

    Science.gov (United States)

    Hue, Pham Thi Bach; Wohlgemuth, Sven; Echizen, Isao; Thuy, Dong Thi Bich; Thuc, Nguyen Dinh

    There needs to be a strategy for securing the privacy of patients when exchanging health records between various entities over the Internet. Despite the fact that health care providers such as Google Health and Microsoft Corp.'s Health Vault comply with the U.S Health Insurance Portability and Accountability Act (HIPAA), the privacy of patients is still at risk. Several encryption schemes and access control mechanisms have been suggested to protect the disclosure of a patient's health record especially from unauthorized entities. However, by implementing these approaches, data owners are not capable of controlling and protecting the disclosure of the individual sensitive attributes of their health records. This raises the need to adopt a secure mechanism to protect personal information against unauthorized disclosure. Therefore, we propose a new Fine-grained Access Control (FGAC) mechanism that is based on subkeys, which would allow a data owner to further control the access to his data at the column-level. We also propose a new mechanism to efficiently reduce the number of keys maintained by a data owner in cases when the users have different access privileges to different columns of the data being shared.

  10. Audit-Based Access Control for Electronic Health Records

    NARCIS (Netherlands)

    Dekker, M.A.C.; Etalle, Sandro

    2006-01-01

    Traditional access control mechanisms aim to prevent illegal actions a-priori occurrence, i.e. before granting a request for a document. There are scenarios however where the security decision can not be made on the fly. For these settings we developed a language and a framework for a-posteriori

  11. Access Control for Agent-based Computing: A Distributed Approach.

    Science.gov (United States)

    Antonopoulos, Nick; Koukoumpetsos, Kyriakos; Shafarenko, Alex

    2001-01-01

    Discusses the mobile software agent paradigm that provides a foundation for the development of high performance distributed applications and presents a simple, distributed access control architecture based on the concept of distributed, active authorization entities (lock cells), any combination of which can be referenced by an agent to provide…

  12. Secure Dynamic access control scheme of PHR in cloud computing.

    Science.gov (United States)

    Chen, Tzer-Shyong; Liu, Chia-Hui; Chen, Tzer-Long; Chen, Chin-Sheng; Bau, Jian-Guo; Lin, Tzu-Ching

    2012-12-01

    With the development of information technology and medical technology, medical information has been developed from traditional paper records into electronic medical records, which have now been widely applied. The new-style medical information exchange system "personal health records (PHR)" is gradually developed. PHR is a kind of health records maintained and recorded by individuals. An ideal personal health record could integrate personal medical information from different sources and provide complete and correct personal health and medical summary through the Internet or portable media under the requirements of security and privacy. A lot of personal health records are being utilized. The patient-centered PHR information exchange system allows the public autonomously maintain and manage personal health records. Such management is convenient for storing, accessing, and sharing personal medical records. With the emergence of Cloud computing, PHR service has been transferred to storing data into Cloud servers that the resources could be flexibly utilized and the operation cost can be reduced. Nevertheless, patients would face privacy problem when storing PHR data into Cloud. Besides, it requires a secure protection scheme to encrypt the medical records of each patient for storing PHR into Cloud server. In the encryption process, it would be a challenge to achieve accurately accessing to medical records and corresponding to flexibility and efficiency. A new PHR access control scheme under Cloud computing environments is proposed in this study. With Lagrange interpolation polynomial to establish a secure and effective PHR information access scheme, it allows to accurately access to PHR with security and is suitable for enormous multi-users. Moreover, this scheme also dynamically supports multi-users in Cloud computing environments with personal privacy and offers legal authorities to access to PHR. From security and effectiveness analyses, the proposed PHR access

  13. Protocol for ACCESS: a qualitative study exploring barriers and facilitators to accessing the emergency contraceptive pill from community pharmacies in Australia

    Science.gov (United States)

    Hussainy, Safeera Yasmeen; Ghosh, Ayesha; Taft, Angela; Mazza, Danielle; Black, Kirsten Isla; Clifford, Rhonda; Mc Namara, Kevin Peter; Ryan, Kath; Jackson, John Keith

    2015-01-01

    Introduction The rate of unplanned pregnancy in Australia remains high, which has contributed to Australia having one of the highest abortion rates of developed countries with an estimated 1 in 5 women having an abortion. The emergency contraceptive pill (ECP) offers a safe way of preventing unintended pregnancy after unprotected sex has occurred. While the ECP has been available over-the-counter in Australian pharmacies for over a decade, its use has not significantly increased. This paper presents a protocol for a qualitative study that aims to identify the barriers and facilitators to accessing the ECP from community pharmacies in Australia. Methods and analysis Data will be collected through one-on-one interviews that are semistructured and in-depth. Partnerships have been established with 2 pharmacy groups and 2 women's health organisations to aid with the recruitment of women and pharmacists for data collection purposes. Interview questions explore domains from the Theoretical Domains Framework in order to assess the factors aiding and/or hindering access to ECP from community pharmacies. Data collected will be analysed using deductive content analysis. The expected benefits of this study are that it will help develop evidence-based workforce interventions to strengthen the capacity and performance of community pharmacists as key ECP providers. Ethics and dissemination The findings will be disseminated to the research team and study partners, who will brainstorm ideas for interventions that would address barriers and facilitators to access identified from the interviews. Dissemination will also occur through presentations and peer-reviewed publications and the study participants will receive an executive summary of the findings. The study has been evaluated and approved by the Monash Human Research Ethics Committee. PMID:26656987

  14. Medium Access Control in Energy Harvesting - Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Fafoutis, Xenofon

    Control (MAC) protocols that are following the receiver-initiated paradigm of asynchronous communication. According to the receiver-initiated paradigm the communication is initiated by the receiver that states its availability to receive data through beacons. The sender is passively listening...... to the channel until it receives the beacon of interest. In this context, the dissertation begins with an in-depth survey of all the receiverinitiated MAC protocols and presents their unique optimization features, which deal with several challenges of the link layer such as mitigation of the energy consumption......-efficient features that aim to adapt the consumed energy to match the harvested energy, distribute the load with respect to the harvested energy, decrease the overhead of the communication, address the requirements for collision avoidance, prioritize urgent traffic and secure the system against beacon replay attacks...

  15. Compulsory licensing, price controls, and access to patented foreign products

    OpenAIRE

    Eric Bond; Kamal Saggi

    2012-01-01

    Motivated by existing multilateral rules regarding intellectual property, we develop a North-South model to highlight the dual roles price controls and compulsory licensing play in determining Southern access to a patented Northern product. The Northern patent-holder chooses whether and how to work its patent in the South (either via entry or voluntarily licensing) while the South determines the price control and whether to issue a compulsory license. The threat of compulsory licensing benefi...

  16. Modemless Multiple Access Communications over Powerlines for DC Microgrid Control

    OpenAIRE

    Angjelichinoski, Marko; Stefanovic, Cedomir; Popovski, Petar

    2016-01-01

    We present a communication solution tailored specifically for DC microgrids (MGs) that exploits: (i) the communication potential residing in power electronic converters interfacing distributed generators to powerlines and (ii) the multiple access nature of the communication channel presented by powerlines. The communication is achieved by modulating the parameters of the primary control loop implemented by the converters, fostering execution of the upper layer control applications. We present...

  17. Integrity Based Access Control Model for Multilevel XML Document

    Institute of Scientific and Technical Information of China (English)

    HONG Fan; FENG Xue-bin; HUANO Zhi; ZHENG Ming-hui

    2008-01-01

    XML's increasing popularity highlights the security demand for XML documents. A mandatory access control model for XML document is presented on the basis of investigation of the function dependency of XML documents and discussion of the integrity properties of multilevel XML document. Then, the algorithms for decomposition/recovery multilevel XML document into/from single level document are given, and the manipulation rules for typical operations of XQuery and XUpdate: QUERY, INSERT,UPDATE, and REMOVE, are elaborated. The multilevel XML document access model can meet the requirement of sensitive information processing application.

  18. Controlling user access to electronic resources without password

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Fred Hewitt

    2017-08-22

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes obtaining an image from a communication device of a user. An individual and a landmark are identified within the image. Determinations are made that the individual is the user and that the landmark is a predetermined landmark. Access to a restricted computing resource is granted based on the determining that the individual is the user and that the landmark is the predetermined landmark. Other embodiments are disclosed.

  19. Conflict resolution protocols for random multiple-access channels with binary feedback

    Science.gov (United States)

    Berger, T.; Mehravari, N.

    The problem of conflict resolution in a random multiple-access, time-slotted, packet-switched channel with binary feedback is considered. Conflict resolution algorithms (CRA) for two different types of binary feedback which informs the users only about whether or not there was a collision in the previous slot achieves a throughput of 0.442. The CRA proposed for the case in which the feedback informs the users about whether or not the previous slot was empty achieves a throughput of 0.279.

  20. Two new Controlled not Gate Based Quantum Secret Sharing Protocols without Entanglement Attenuation

    Science.gov (United States)

    Zhu, Zhen-Chao; Hu, Ai-Qun; Fu, An-Min

    2016-05-01

    In this paper, we propose two new controlled not gate based quantum secret sharing protocols. In these two protocols, each photon only travels once, which guarantees the agents located in long distance can be able to derive the dealer's secret without suffering entanglement attenuation problem. The protocols are secure against trojan horse attack, intercept-resend attack, entangle-measure attack and entanglement-swapping attack. The theoretical efficiency for qubits of these two protocols can approach 100 %, except those used for eavesdropping checking, all entangled states can be used for final secret sharing.

  1. Comparison of an intermittent and continuous forearm muscles fatigue protocol with motorcycle riders and control group.

    Science.gov (United States)

    Marina, M; Torrado, P; Busquets, A; Ríos, J G; Angulo-Barroso, R

    2013-02-01

    Motorcycle races' long duration justify the study of forearm muscles fatigue, especially knowing the frequently associated forearm discomfort pathology. Moreover, while continuous fatigue protocols yield unequivocal results, EMG outcomes from an intermittent protocol are quite controversial. This study examined the forearm muscle fatigue patterns produced during these two protocols, comparing riders with a control group, and relating maximal voluntary contraction with EMG parameters (amplitude - NRMS and median frequency - NMF) of both protocols to the forearm discomfort among motorcycle riders. Twenty riders and 39 controls performed in separate days both protocols simulating the braking gesture and posture of a rider. EMG of flexor digitorum superficialis (FS) and carpi radialis (CR) were monitored. CR revealed more differences among protocols and groups compared to FS. The greater CR activation in riders could be interpreted as a neuromotor strategy to improve braking precision. When FS fatigue increased, the control group progressively shift toward a bigger CR activation, adopting an intermuscular activation pattern closer to riders. Despite the absence of NMF decrement throughout the intermittent protocol, which suggest that we should have shorten the recovery times from the actual 1 min, the superior number of rounds performed by the riders proved that this protocol discriminates better riders against controls and is more related to forearm discomfort.

  2. Overriding follicle selection in controlled ovarian stimulation protocols: Quality vs quantity

    Directory of Open Access Journals (Sweden)

    Zelinski-Wooten Mary B

    2004-06-01

    Full Text Available Abstract Selection of the species-specific number of follicles that will develop and ovulate during the ovarian cycle can be overridden by increasing the levels of pituitary gonadotropin hormones, FSH and LH. During controlled ovarian stimulation (COS in nonhuman primates for assisted reproductive technology (ART protocols, the method of choice (but not the only method has been the administration of exogenous gonadotropins, either of nonprimate or primate origin. Due to species-specificity of the primate LH (but not FSH receptor, COS with nonprimate (e.g., PMSG hormones can be attributed to their FSH activity. Elevated levels of FSH alone will produce large antral follicles containing oocytes capable of fertilization in vitro (IVF. However, there is evidence that LH, probably in lesser amounts, increases the rate of follicular development, reduces heterogeneity of the antral follicle pool, and improves the viability and rate of pre-implantation development of IVF-produced embryos. Since an endogenous LH surge typically does not occur during COS cycles (especially when a GnRH antagonist is added, a large dose of an LH-like hormone (i.e., hCG may be given to reinitiate meiosis and produce fertilizable oocytes. Alternate approaches using exogenous LH (or FSH, or GnRH agonist to induce an endogenous LH surge, have received lesser attention. Current protocols will routinely yield dozens of large follicles with fertilizable eggs. However, limitations include non/poor-responding animals, heterogeneity of follicles (and presumably oocytes and subsequent short luteal phases (limiting embryo transfer in COS cycles. However, the most serious limitation to further improvements and expanded use of COS protocols for ART is the lack of availability of nonhuman primate gonadotropins. Human, and even more so, nonprimate gonadotropins are antigenic in monkeys, which limits the number of COS cycles to as few as 1 (PMSG or 3 (recombinant hCG protocols in macaques

  3. Quantum control without access to the controlling interaction

    CERN Document Server

    Janzing, D; Zeier, R; Beth, T; Janzing, Dominik; Armknecht, Frederik; Zeier, Robert; Beth, Thomas

    2001-01-01

    In our model a fixed Hamiltonian acts on the joint Hilbert space of a quantum system and its controller. We show under which conditions measurements, state preparations, and unitary implementations on the system can be performed by quantum operations on the controller only. It turns out that a measurement of the observable A and an implementation of the one-parameter group exp(iAr) can be performed by almost the same sequence of control operations. Furthermore measurement procedures for A+B, for (AB+BA), and for i[A,B] can be constructed from measurements of A and B. This shows that the algebraic structure of the set of observables can be explained by the Lie group structure of the unitary evolutions on the joint Hilbert space of the measuring device and the measured system. A spin chain model with nearest neighborhood coupling shows that the border line between controller and system can be shifted consistently.

  4. A Self-Learning MAC Protocol for Energy Harvesting and Spectrum Access in Cognitive Radio Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mohammed Hawa

    2016-01-01

    Full Text Available The fusion of Wireless Sensor Networks (WSNs and Cognitive Radio Networks (CRNs into Cognitive Radio Sensor Networks (CRSNs is quite an attractive proposal, because it allows a distributed set of low-powered sensor nodes to opportunistically access spectrum bands that are underutilized by their licensed owners (called primary users (PUs. In addition, when the PUs are actively transmitting in their own bands, sensor nodes can switch to energy harvesting mode to obtain their energy needs (for free, to achieve almost perpetual life. In this work, we present a novel and fully distributed MAC protocol, called S-LEARN, that allows sensor nodes in a CRSN to entwine their RF energy harvesting and data transmission activities, while intelligently addressing the issue of disproportionate difference between the high power necessary for the node to transmit data packets and the small amount of power it can harvest wirelessly from the environment. The presented MAC protocol can improve both the network throughput and total harvested energy, while being robust to changes in the network configuration. Moreover, S-LEARN can keep the cost of the system low, and it avoids the pitfalls from which centralized systems suffer.

  5. Application of Attribute Based Access Control Model for Industrial Control Systems

    Directory of Open Access Journals (Sweden)

    Erkan Yalcinkaya

    2017-02-01

    Full Text Available The number of reported security vulnerabilities and incidents related to the industrial control systems (ICS has increased recent years. As argued by several researchers, authorization issues and poor access control are key incident vectors. The majority of ICS are not designed security in mind and they usually lack strong and granular access control mechanisms. The attribute based access control (ABAC model offers high authorization granularity, central administration of access policies with centrally consolidated and monitored logging properties. This research proposes to harness the ABAC model to address the present and future ICS access control challenges. The proposed solution is also implemented and rigorously tested to demonstrate the feasibility and viability of ABAC model for ICS.

  6. Vulnerability Analysis of the Player Command and Control Protocol

    Science.gov (United States)

    2012-06-14

    following sections outline a design recovery of the Pl~:wer protocol uf.led in va.0.2. 2. /1.3.1 XDH. PJayor usos dw IETF !’Lnnda.rd: ExtH’IHl.J Da\\.;1...1\\Jcss<Jgc <Hl tlwn tic <J tion codes (MAC) work similarly to cryptographic hash functions except that rather than using public-key cryptography

  7. Draft Protocol for Controlling Contaminated Groundwater by Phytostabilization

    Science.gov (United States)

    1999-11-05

    Phytoextraction is usually associated with metal contaminants. Plants called hyperaccumulators absorb large amounts of metals in comparison to other... hyperaccumulation of metals have not been included. Applied Natural Sciences 4129 Tonya Trail Fairfield, OH 45011 Phone: 513-895-6061 Fax: 513-895-6062 Ecolotree...with or, in some cases, in place of mechanical cleanup methods. Phytoremediation can be used to clean up metals , pesticides, Draft Protocol for

  8. Unsynchronized Energy-Efficient Medium Access Control and Routing in Wireless Sensor Networks

    Science.gov (United States)

    Hurni, Philipp

    This master thesis investigates optimizations on recently proposed fully unsynchronized power saving sensor MAC protocols. In contrast to many other sensor MAC protocols, unsynchronized sensor MAC protocols renounce on any kind of network- or cluster-wide synchronization for channel access coordination and maintenance of a common wake-sleep pattern, because in wireless sensor networks with low traffic requirements, the overhead for maintaining synchronization is likely to exceed the energy spent for the actual data traffic.

  9. Global system data bus using the Digital Autonomous Terminal Access Communication protocol

    Science.gov (United States)

    Holmes, David C. E.

    1986-01-01

    Modern digital avionic systems with distributed processing require networking to connect the many elements. Digital Autonomous Terminal Access Communication (DATAC) is one of many such networks. DATAC has been implemented on the Transport Systems Research Vehicle (TSRV), a Boeing 737 aircraft operated by the National Aeronautics and Space Administration's Advanced Transport Operating Systems Program Office (ATOPS). This paper presents the TSRV implementation of the DATAC bus, a description of the DATAC system, a synchronization mechanism, details of data flow throughout the system, and a discussion of the modes available with DATAC. Numerous flight tests have been conducted using DATAC as the only means of communication between systems with outstanding results. DATAC is now an integral part of the TSRV and is expected to satisfy near term as well as future requirements for growth and flexibility.

  10. An Energy Efficient Protocol for Gateway-Centric Federated Residential Access Networks

    CERN Document Server

    Rossi, Claudio; Chiasserini, Carla-Fabiana

    2011-01-01

    The proliferation of overlapping, always-on IEEE 802.11 Access Points (APs) in urban areas can cause spectrum sharing conflicts, inefficient bandwidth usage and power waste. Cooperation among APs could address these problems (i) by allowing under-used devices to hand over their clients to nearby APs and temporarily switch off, (ii) by balancing the load of clients among APs and thus offloading congested APs. The federated houses model provides an appealing backdrop to implement cooperation among APs. In this paper, we outline a framework that, assuming the presence of a multipurpose gateway with AP capabilities in every household, allows such cooperation through the monitoring of local wireless resources and the triggering of offloading requests toward other federated gateways. We then present simulation results in realistic settings that provide some insight on the capabilities of our framework.

  11. A formal model for access control with supporting spatial context

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong; HE YePing; SHI ZhiGuo

    2007-01-01

    There is an emerging recognition of the importance of utilizing contextual information in authorization decisions. Controlling access to resources in the field of wireless and mobile networking require the definition of a formal model for access control with supporting spatial context. However, traditional RBAC model does not specify these spatial requirements. In this paper, we extend the existing RBAC model and propose the SC-RBAC model that utilizes spatial and location-based information in security policy definitions. The concept of spatial role is presented,and the role is assigned a logical location domain to specify the spatial boundary.Roles are activated based on the current physical position of the user which obtained from a specific mobile terminal. We then extend SC-RBAC to deal with hierarchies, modeling permission, user and activation inheritance, and prove that the hierarchical spatial roles are capable of constructing a lattice which is a means for articulate multi-level security policy and more suitable to control the information flow security for safety-critical location-aware information systems. Next, constrained SC-RBAC allows express various spatial separations of duty constraints,location-based cardinality and temporal constraints for specify fine-grained spatial semantics that are typical in location-aware systems. Finally, we introduce 9 invariants for the constrained SC-RBAC and its basic security theorem is proven. The constrained SC-RBAC provides the foundation for applications in need of the constrained spatial context aware access control.

  12. Generalized access control strategies for integrated services token passing systems

    Science.gov (United States)

    Pang, Joseph W. M.; Tobagi, Fouad A.; Boyd, Stephen

    1994-08-01

    The demand for integrated services local area networks is increasing at a rapid pace with the advent of many new and exciting applications: office and factory automation, distributed computing, and multimedia communications. To support these new applications, it is imperative to integrate traffic with diverse statistical characteristics and differing delay requirements on the same network. An attractive approach for integrating traffic has been adopted in two token passing local area network standards, the IEEE 802.4 token bus standard and FDDI. The idea is to control the transmissions of each station based on a distributed timing algorithm, so as to achieve the following goals: (1) to limit the token cycles so that time-critical traffic can be accommodated, and (2) to allocate pre-specified bandwidths to different stations when the network is overloaded. We have investigated the analysis and design of this protocol. In this paper, we generalize the transmission control algorithm used previously. The major advantages of the generalization over the original protocol are: (1) it provides a much expanded design space, (2) it guarantees convergent behavior, and (3) it gives meaningful insights into the dynamics of the basic control algorithm.

  13. Secure Communication and Access Control for Mobile Web Service Provisioning

    CERN Document Server

    Srirama, Satish Narayana

    2010-01-01

    It is now feasible to host basic web services on a smart phone due to the advances in wireless devices and mobile communication technologies. While the applications are quite welcoming, the ability to provide secure and reliable communication in the vulnerable and volatile mobile ad-hoc topologies is vastly becoming necessary. The paper mainly addresses the details and issues in providing secured communication and access control for the mobile web service provisioning domain. While the basic message-level security can be provided, providing proper access control mechanisms for the Mobile Host still poses a great challenge. This paper discusses details of secure communication and proposes the distributed semantics-based authorization mechanism.

  14. NCSA: A New Protocol for Random Multiple Access Based on Physical Layer Network Coding

    CERN Document Server

    Bui, Huyen Chi; Boucheret, Marie-Laure

    2010-01-01

    This paper introduces a random multiple access method for satellite communications, named Network Coding-based Slotted Aloha (NCSA). The goal is to improve diversity of data bursts on a slotted-ALOHA-like channel thanks to error correcting codes and Physical-layer Network Coding (PNC). This scheme can be considered as a generalization of the Contention Resolution Diversity Slotted Aloha (CRDSA) where the different replicas of this system are replaced by the different parts of a single word of an error correcting code. The performance of this scheme is first studied through a density evolution approach. Then, simulations confirm the CRDSA results by showing that, for a time frame of $400$ slots, the achievable total throughput is greater than $0.7\\times C$, where $C$ is the maximal throughput achieved by a centralized scheme. This paper is a first analysis of the proposed scheme which open several perspectives. The most promising approach is to integrate collided bursts into the decoding process in order to im...

  15. Implementation of anomaly detection algorithms for detecting transmission control protocol synchronized flooding attacks

    CSIR Research Space (South Africa)

    Mkuzangwe, NNP

    2015-08-01

    Full Text Available This work implements two anomaly detection algorithms for detecting Transmission Control Protocol Synchronized (TCP SYN) flooding attack. The two algorithms are an adaptive threshold algorithm and a cumulative sum (CUSUM) based algorithm...

  16. An approach to access control in electronic health record.

    Science.gov (United States)

    Sucurovic, Snezana

    2010-08-01

    OASIS is a non-for-profit consortium that drives the development convergence and adoption of open standards for the global information society. It involves more than 600 organizations and individuals as well as IT leaders Sun, Microsoft, IBM and Oracle. One of its standards is XACML which appeared a few years ago and now there are about 150,000 hits on Google. XACML (eXtensible Access Control Markup Language) is not technology related. Sun published in 2004 open source Sun XACML which is in compliance with XACML 1.0. specification and now works to make it comply with XACML 2.0. The heart of XACML are attributes values of defined type and name that is to be attached to a subject, a resource, an action and an environment in which a subject request action on resource. In that way XACML is to replace Role Based Access Control which dominated for years. The paper examines performances in CEN 13 606 and ISO 22 600 based healthcare system which uses XACML for access control.

  17. Authorisation and access control for electronic health record systems.

    Science.gov (United States)

    Blobel, Bernd

    2004-03-31

    Enabling the shared care paradigm, centralised or even decentralised electronic health record (EHR) systems increasingly become core applications in hospital information systems and health networks. For realising multipurpose use and reuse as well as inter-operability at knowledge level, EHR have to meet special architectural requirements. The component-oriented and model-based architecture should meet international standards. Especially in extended health networks realising inter-organisational communication and co-operation, authorisation cannot be organised at user level anymore. Therefore, models, methods and tools must be established to allow formal and structured policy definition, policy agreements, role definition, authorisation and access control. Based on the author's international engagement in EHR architecture and security standards referring to the revision of CEN ENV 13606, the GEHR/open EHR approach, HL7 and CORBA, models for health-specific and EHR-related roles, for authorisation management and access control have been developed. The basic concept is the separation of structural roles defining organisational entity-to-entity relationships and enabling specific acts on the one hand, and functional roles bound to specific activities and realising rights and duties on the other hand. Aggregation of organisational, functional, informational and technological components follows specific rules. Using UML and XML, the principles as well as some examples for analysis, design, implementation and maintenance of policy and authorisation management as well as access control have been practically implemented.

  18. Channel Access in Erlang

    Energy Technology Data Exchange (ETDEWEB)

    Nicklaus, Dennis J. [Fermilab

    2013-10-13

    We have developed an Erlang language implementation of the Channel Access protocol. Included are low-level functions for encoding and decoding Channel Access protocol network packets as well as higher level functions for monitoring or setting EPICS process variables. This provides access to EPICS process variables for the Fermilab Acnet control system via our Erlang-based front-end architecture without having to interface to C/C++ programs and libraries. Erlang is a functional programming language originally developed for real-time telecommunications applications. Its network programming features and list management functions make it particularly well-suited for the task of managing multiple Channel Access circuits and PV monitors.

  19. Development of a Web-Accessible Population Pharmacokinetic Service—Hemophilia (WAPPS-Hemo): Study Protocol

    Science.gov (United States)

    Foster, Gary; Navarro-Ruan, Tamara; McEneny-King, Alanna; Edginton, Andrea N; Thabane, Lehana

    2016-01-01

    Background Individual pharmacokinetic assessment is a critical component of tailored prophylaxis for hemophilia patients. Population pharmacokinetics allows using individual sparse data, thus simplifying individual pharmacokinetic studies. Implementing population pharmacokinetics capacity for the hemophilia community is beyond individual reach and requires a system effort. Objective The Web-Accessible Population Pharmacokinetic Service—Hemophilia (WAPPS-Hemo) project aims to assemble a database of patient pharmacokinetic data for all existing factor concentrates, develop and validate population pharmacokinetics models, and integrate these models within a Web-based calculator for individualized pharmacokinetic estimation in patients at participating treatment centers. Methods Individual pharmacokinetic studies on factor VIII and IX concentrates will be sourced from pharmaceutical companies and independent investigators. All factor concentrate manufacturers, hemophilia treatment centers (HTCs), and independent investigators (identified via a systematic review of the literature) having on file pharmacokinetic data and willing to contribute full or sparse pharmacokinetic data will be eligible for participation. Multicompartmental modeling will be performed using a mixed-model approach for derivation and Bayesian forecasting for estimation of individual sparse data. NONMEM (ICON Development Solutions) will be used as modeling software. Results The WAPPS-Hemo research network has been launched and is currently joined by 30 HTCs from across the world. We have gathered dense individual pharmacokinetic data on 878 subjects, including several replicates, on 21 different molecules from 17 different sources. We have collected sparse individual pharmacokinetic data on 289 subjects from the participating centers through the testing phase of the WAPPS-Hemo Web interface. We have developed prototypal population pharmacokinetics models for 11 molecules. The WAPPS-Hemo website

  20. A COMBINED ADMISSION CONTROL ALGORITHM WITH DA PROTOCOL FOR SATELLITE ATM NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Lu Rong; Cao Zhigang

    2006-01-01

    Admission control is an important strategy for Quality of Service (QoS) provisioning in Asynchronous Transfer Mode (ATM) networks. Based on a control-theory model of resources on-Demand Allocation (DA) protocol, the paper studies the effect of the protocol on the statistical characteristics of network traffic,and proposes a combined connection admission control algorithm with the DA protocol to achieve full utilization of link resources in satellite communication systems. The proposed algorithm is based on the cross-layer-design approach. Theoretical analysis and system simulation results show that the proposed algorithm can admit more connections within certain admission thresholds than one that does not take into account the DA protocol. Thus, the proposed algorithm can increase admission ratio of traffic sources for satellite ATM networks and improve satellite link utilization.

  1. OJADEAC: An Ontology Based Access Control Model for JADE Platform

    Directory of Open Access Journals (Sweden)

    Ban Sharief Mustafa

    2014-06-01

    Full Text Available Java Agent Development Framework (JADE is a software framework to make easy the development of Multi-Agent applications in compliance with the Foundation for Intelligent Physical Agents (FIPA specifications. JADE propose new infrastructure solutions to support the development of useful and convenient distributed applications. Security is one of the most important issues in implementing and deploying such applications. JADE-S security add-ons are one of the most popular security solutions in JADE platform. It provides several security services including authentication, authorization, signature and encryption services. Authorization service will give authorities to perform an action based on a set of permission objects attached to every authenticated user. This service has several drawbacks when implemented in a scalable distributed context aware applications. In this paper, an ontology-based access control model called (OJADEAC is proposed to be applied in JADE platform by combining Semantic Web technologies with context-aware policy mechanism to overcome the shortcoming of this service. The access control model is represented by a semantic ontology, and a set of two level semantic rules representing platform and application specific policy rules. OJADEAC model is distributed, intelligent, dynamic, context-aware and use reasoning engine to infer access decisions based on ontology knowledge.

  2. A study of multiple access schemes in satellite control network

    Science.gov (United States)

    Mo, Zijian; Wang, Zhonghai; Xiang, Xingyu; Wang, Gang; Chen, Genshe; Nguyen, Tien; Pham, Khanh; Blasch, Erik

    2016-05-01

    Satellite Control Networks (SCN) have provided launch control for space lift vehicles; tracking, telemetry and commanding (TTC) for on-orbit satellites; and, test support for space experiments since the 1960s. Currently, SCNs encounter a new challenge: how to maintain the high reliability of services when sharing the spectrum with emerging commercial services. To achieve this goal, the capability of multiple satellites reception is deserved as an update/modernization of SCN in the future. In this paper, we conducts an investigation of multiple access techniques in SCN scenario, e.g., frequency division multiple access (FDMA) and coded division multiple access (CDMA). First, we introduce two upgrade options of SCN based on FDMA and CDMA techniques. Correspondingly, we also provide their performance analysis, especially the system improvement in spectrum efficiency and interference mitigation. Finally, to determine the optimum upgrade option, this work uses CRISP, i.e., Cost, Risk, Installation, Supportability and Performance, as the baseline approach for a comprehensive trade study of these two options. Extensive numerical and simulation results are presented to illustrate the theoretical development.

  3. In silico evaluation of glucose control protocols for critically ill patients.

    Science.gov (United States)

    Lee, Jung Chan; Kim, Myeungseon; Choi, Ka Ram; Oh, Tae Jung; Kim, Min Young; Cho, Young Min; Kim, Kyuseok; Kim, Hee Chan; Kim, Sungwan

    2012-01-01

    This letter presents an in silico evaluation method of glucose control protocols for critically ill patients with hyperglycemia. Although various glucose control protocols were introduced and investigated in clinical trials, development and validation of a novel glucose control protocol for critically ill patients require too much time and resources in clinical evaluation. We employed a virtual patient model of the critically ill patient with hyperglycemia and evaluated the clinically investigated glucose control protocols in a computational environment. The three-day simulation results presented the time profiles of glucose and insulin concentrations, the amount of enteral feed and intravenous bolus of glucose, and the intravenous insulin infusion rate. The hyperglycemia and hypoglycemia index, blood glucose concentrations, insulin doses, intravenous glucose infusion rates, and glucose feed rates were compared between different protocols. It is shown that a similar hypoglycemia incidence exists in simulation and clinical results. We concluded that this in silico simulation method using a virtual patient model could be useful for predicting hypoglycemic incidence of novel glucose control protocols for critically ill patients, prior to clinical trials. © 2011 IEEE

  4. Validation concurrency control protocol in parallel real-time database systems

    Institute of Scientific and Technical Information of China (English)

    雷向东; 袁晓莉

    2002-01-01

    In parallel real-time database systems, concurrency control protocols must satisfy time constraints as well as the integrity constraints. The authors present a validation concurrency control(VCC) protocol, which can enhance the performance of real-time concurrency control mechanism by reducing the number of transactions that might miss their deadlines, and compare the performance of validation concurrency control protocol with that of HP2PL(High priority two phase locking) protocol and OCC-TI-WAIT-50(Optimistic concurrency control-time interval-wait-50) protocol under shared-disk architecture by simulation. The simulation results reveal that the protocol the author presented can effectively reduce the number of transactions restarting which might miss their deadlines and performs better than HP2PL and OCC-TI-WAIT-50. It works well when arrival rate of transaction is lesser than threshold. However, due to resource contention the percentage of missing deadline increases sharply when arrival rate is greater than the threshold.

  5. Access Control Model for Sharing Composite Electronic Health Records

    Science.gov (United States)

    Jin, Jing; Ahn, Gail-Joon; Covington, Michael J.; Zhang, Xinwen

    The adoption of electronically formatted medical records, so called Electronic Health Records (EHRs), has become extremely important in healthcare systems to enable the exchange of medical information among stakeholders. An EHR generally consists of data with different types and sensitivity degrees which must be selectively shared based on the need-to-know principle. Security mechanisms are required to guarantee that only authorized users have access to specific portions of such critical record for legitimate purposes. In this paper, we propose a novel approach for modelling access control scheme for composite EHRs. Our model formulates the semantics and structural composition of an EHR document, from which we introduce a notion of authorized zones of the composite EHR at different granularity levels, taking into consideration of several important criteria such as data types, intended purposes and information sensitivities.

  6. Multi-channel Dual Clocks three-dimensional probability Random Multiple Access protocol for Wireless Public Bus Networks based on RTS/CTS mechanism

    Directory of Open Access Journals (Sweden)

    Zhou Sheng Jie

    2016-01-01

    Full Text Available A MAC protocol for public bus networks, called Bus MAC protocol, designed to provide high quality Internet service for bus passengers. The paper proposed a multi-channel dual clocks three-demission probability random multiple access protocol based on RTS/CTS mechanism, decreasing collisions caused by multiple access from multiple passengers. Use the RTS/CTS mechanism increases the reliability and stability of the system, reducing the collision possibility of the information packets to a certain extent, improves the channel utilization; use the multi-channel mechanism, not only enables the channel load balancing, but also solves the problem of the hidden terminal and exposed terminal. Use the dual clocks mechanism, reducing the system idle time. At last, the different selection of the three-dimensional probabilities can make the system throughput adapt to the network load which could realize the maximum of the system throughput.

  7. Protocol for economic evaluation alongside the IMPLEMENT cluster randomised controlled trial

    Directory of Open Access Journals (Sweden)

    McKenzie Joanne E

    2008-02-01

    Full Text Available Abstract Background The recent development and publication of evidence-based clinical practice guidelines (CPGs for acute low back pain (LBP has resulted in evidence-based recommendations that, if implemented, have the potential to improve the quality and safety of care for acute LBP. While a strategy has been specified for dissemination of the CPG for acute LBP in Australia, there is no accompanying plan for active implementation. Evidence regarding the cost-effectiveness of active implementation of CPGs for acute LBP is sparse. The IMPLEMENT study will consider the incremental benefits and costs of progressing beyond development and dissemination to implementation. Methods/design Cost-effectiveness and cost-utility analyses alongside the IMPLEMENT cluster randomised controlled trial (CRCT from a societal perspective to quantify the additional costs (savings and health gains associated with a targeted implementation strategy as compared with access to the CPG via dissemination only. Discussion The protocol provided here registers our intent to conduct an economic evaluation alongside the IMPLEMENT study, facilitates peer-review of proposed methods and provides a transparent statement of planned analyses. Trial registration Australian New Zealand Clinical Trials Registry ACTRN012606000098538

  8. Dissemination Protocols to Support Cooperative Adaptive Cruise Control (CACC) Merging

    NARCIS (Netherlands)

    Klein Wolterink, W.; Heijenk, Geert; Karagiannis, Georgios

    2011-01-01

    Cooperative adaptive cruise control (CACC) is a form of cruise control in which vehicles cooperatively control their speed using wireless communication. Previously we have implemented CACC using beaconing: the regular broadcasting of status information using 802.11p. Currently we are concerned with

  9. Protocol converter for serial communication between digital rectifier controllers and a power plant SCADA system

    Directory of Open Access Journals (Sweden)

    Vukić Vladimir Đ.

    2016-01-01

    Full Text Available The paper describes the protocol converter INT-485-MBRTU, developed for serial communication between the thyristor rectifier (based on the proprietary protocol "INT-CPD-05", according to standard RS-485 and the SCADA system (based on protocol "Modbus RTU", of the same standard in the thermal power plant "Nikola Tesla B1". Elementary data on industrial communication protocols and communication gateways were provided. The basic technical characteristics of the "Omron" programmable logic controller CJ series were described, as well as the developed device INT-485-MBRTU. Protocol converters with two versions of communication software were tested, differing only in one control word, intended for a forced successive change of communication sequences, in opposite to automatic sequence relieve. The device iNT-485-MBRTU, with the program for forced successive change of communication sequences, demonstrated the reliability of data transfer of 100 %, in a sample of approximately 480 messages. For nearly the same sample, the same protocol converter, with a version of the program without any type of message identifiers, transferred less than 60 % of the foreseen data. During multiple sixty-hour tests, the reliability of data transfer of at least 99.9979% was recorded, in 100% of the analysed cases, and for a sample of nearly 96,000 pairs of the send and receive messages. We analysed the results and estimated the additional possibilities for application of the INT-485-MBRTU protocol converter.

  10. Evaluation of secure capability-based access control in the M2M local cloud platform

    DEFF Research Database (Denmark)

    Anggorojati, Bayu; Prasad, Neeli R.; Prasad, Ramjee

    2016-01-01

    of multiple distributed M2M gateways, creating new challenges in the access control. Some existing access control systems lack in scalability and flexibility to manage access from users or entity that belong to different authorization domains, or fails to provide fine grained and flexible access right...... delegation. Recently, the capability based access control has been considered as method to manage access in the Internet of Things (IoT) or M2M domain. In this paper, the implementation and evaluation of a proposed secure capability based access control in the M2M local cloud platform is presented...

  11. Design and Analysis on Error Handing and Controlling Protocol in Mobile Payment

    Directory of Open Access Journals (Sweden)

    Yong Xu

    2012-02-01

    Full Text Available On purpose to study and solve the mobile payment problems based on MPTP in China, this paper proposed to put forward Error Handling and Controlling Protocol (EHCP and describe this protocol and the execution process. EHCP is aimed to perfect mobile payment communication mechanism and further solve mobile payment security issues in order to make mobile payment becomes more widely accepted. Messages sending and receiving among three parties in the payment system is described. Finally, the analysis illustrates that our protocol achieves the goals of high security, fairness and efficiency.

  12. Analysis and Application of Covert Channels of Internet Control Message Protocol

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xueguang; ZHANG Huanguo

    2006-01-01

    Based on the analysis of the covert channel's working mechanism of the internet control message protocol (ICMP) in internet protocol version 4 (IPv4) and Internet Protocol version 6 (IPv6), the ICMP covert channel's algorithms of the IPv4 and IPv6 are presented, which enable automatic channeling upon IPv4/v6 nodes with non-IPv4-compatible address, and the key transmission is achieved by using this channel in the embedded Internet terminal. The result shows that the covert channel's algorithm, which we implemented if, set correct, the messages of this covert channel might go through the gateway and enter the local area network.

  13. Admission Control and Interference Management in Dynamic Spectrum Access Networks

    Directory of Open Access Journals (Sweden)

    Jorge Martinez-Bauset

    2010-01-01

    Full Text Available We study two important aspects to make dynamic spectrum access work in practice: the admission policy of secondary users (SUs to achieve a certain degree of quality of service and the management of the interference caused by SUs to primary users (PUs. In order to limit the forced termination probability of SUs, we evaluate the Fractional Guard Channel reservation scheme to give priority to spectrum handovers over new arrivals. We show that, contrary to what has been proposed, the throughput of SUs cannot be maximized by configuring the reservation parameter. We also study the interference caused by SUs to PUs. We propose and evaluate different mechanisms to reduce the interference, which are based on simple spectrum access algorithms for both PUs and SUs and channel repacking algorithms for SUs. Numerical results show that the reduction can be of one order of magnitude or more with respect to the random access case. Finally, we propose an adaptive admission control scheme that is able to limit simultaneously the forced termination probability of SUs and what we define as the probability of interference. Our scheme does not require any configuration parameters beyond the probability objectives. Besides, it is simple to implement and it can operate with any arrival process and distribution of the session duration.

  14. GSR-TDMA: A Geometric Spatial Reuse-Time Division Multiple Access MAC Protocol for Multihop Underwater Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Changho Yun

    2016-01-01

    Full Text Available The nonnegligible propagation delay of acoustic signals causes spatiotemporal uncertainty that occasionally enables simultaneous, collision-free packet transmission among underwater nodes (UNs. These transmissions can be handled by efficiently managing the channel access of the UNs in the data-link layer. To this end, Geometric Spatial Reuse-TDMA (GSR-TDMA, a new TDMA-based MAC protocol, is designed for use in centralized, multihop underwater acoustic sensor networks (UASNs, and in this case all UNs are periodically scheduled after determining a geometric map according to the information on their location. The scheduling strategy increases the number of UNs that send packets coincidentally via two subscheduling configurations (i.e., interhop and intrahop scheduling. Extensive simulations are used to investigate the reception success rate (RSR and the multihop delay (MHD of GSR-TDMA, and the results are compared to those of previous approaches, including C-MAC and HSR-TDMA. GSR-TDMA outperforms C-MAC; the RSR of GSR-TDMA is 15% higher than that of C-MAC, and the MHD of GSR-TDMA is 30% lower than that of C-MAC at the most. In addition, GSR-TDMA provides even better performance improvements over HSR-TDMA; the RSR of GSR-TDMA is 50% higher than that of HSR-TDMA, and the MHD of GSR-TDMA is an order of 102 lower than that of HSR-TDMA at the most.

  15. An Access Control Model of Virtual Machine Security

    Directory of Open Access Journals (Sweden)

    QIN Zhong-yuan

    2013-07-01

    Full Text Available Virtualization technology becomes a hot IT technolo gy with the popu-larity of Cloud Computing. However, new security issues arise with it. Specifically, the resources sharing and data communication in virtual machines are most con cerned. In this paper an access control model is proposed which combines the Chinese Wall a nd BLP model. BLP multi-level security model is introduced with corresponding improvement based on PCW (Prioritized Chinese Wall security model. This model can be used to safely co ntrol the resources and event behaviors in virtual machines. Experimental results show its eff ectiveness and safety.

  16. Privacy and Access Control for IHE-Based Systems

    Science.gov (United States)

    Katt, Basel; Breu, Ruth; Hafner, Micahel; Schabetsberger, Thomas; Mair, Richard; Wozak, Florian

    Electronic Health Record (EHR) is the heart element of any e-health system, which aims at improving the quality and efficiency of healthcare through the use of information and communication technologies. The sensitivity of the data contained in the health record poses a great challenge to security. In this paper we propose a security architecture for EHR systems that are conform with IHE profiles. In this architecture we are tackling the problems of access control and privacy. Furthermore, a prototypical implementation of the proposed model is presented.

  17. Efficient identity management and access control in cloud environment

    Science.gov (United States)

    Gloster, Jonathan

    2013-05-01

    As more enterprises are enticed to move data to a cloud environment to enhance data sharing and reduce operating costs by exploiting shared resources, concerns have risen over the ability to secure information within the cloud. This paper examines how a traditional Identity and Access Control (IDAM) architecture can be adapted to address security concerns of a cloud environment. We propose changing the paradigm of IDAM form a pure trust model to a risk based model will enable information to be protected securely in a cloud environment without impacting efficiencies of cloud environments.

  18. Coded Splitting Tree Protocols

    DEFF Research Database (Denmark)

    Sørensen, Jesper Hemming; Stefanovic, Cedomir; Popovski, Petar

    2013-01-01

    This paper presents a novel approach to multiple access control called coded splitting tree protocol. The approach builds on the known tree splitting protocols, code structure and successive interference cancellation (SIC). Several instances of the tree splitting protocol are initiated, each...... instance is terminated prematurely and subsequently iterated. The combined set of leaves from all the tree instances can then be viewed as a graph code, which is decodable using belief propagation. The main design problem is determining the order of splitting, which enables successful decoding as early...... as possible. Evaluations show that the proposed protocol provides considerable gains over the standard tree splitting protocol applying SIC. The improvement comes at the expense of an increased feedback and receiver complexity....

  19. (dtltt) protocol

    African Journals Online (AJOL)

    2013-03-01

    Mar 1, 2013 ... Keywords: multi-access, multiservice, network, synchronous, asynchronous, traffic, timed-token. 1. ... 12, 13 ] SAFENET [14], Manufacturing Automation. Protocol (MAP) ...... ken circulation on mobile Ad Hoc Networks. 21th In-.

  20. Advent of Biometric Sensors in Field of Access Control

    Directory of Open Access Journals (Sweden)

    Ali Anas

    2015-09-01

    Full Text Available Biometrics is the science of measuring and analyzing biological data. It is used to uniquely identify individuals by their physical characteristics or personal behavior traits.The results from scrutiny of various themes including unimodal, multimodal, physiological, behavioural bio-metrics. Bio-metrics, Physiological and behavioural are compared in the review. The article addresses a particular aspect of utilizing biometrics for authentication, identification and access control. The use of systems like fingerprint, face recognition, hand geometry, Palm print, DNA analysis, iris recognition, retina and odour/scent will be dealt with herewith. This study deals with various applications of this technology, like surveillance, employee identification, device access etc with mentions respective of hardware used. The influence of such features is yet to be documented properly, but it is safe to say that it has been a huge step towards better information security and identification control.Over the course of this text, we will try to bring to light our analysis of the subject and provide an in-depth examination of contemporary and futuristic technologies pertaining to this field.

  1. Performance Evaluation of a SLA Negotiation Control Protocol for Grid Networks

    Science.gov (United States)

    Cergol, Igor; Mirchandani, Vinod; Verchere, Dominique

    A framework for an autonomous negotiation control protocol for service delivery is crucial to enable the support of heterogeneous service level agreements (SLAs) that will exist in distributed environments. We have first given a gist of our augmented service negotiation protocol to support distinct service elements. The augmentations also encompass related composition of the services and negotiation with several service providers simultaneously. All the incorporated augmentations will enable to consolidate the service negotiation operations for telecom networks, which are evolving towards Grid networks. Furthermore, our autonomous negotiation protocol is based on a distributed multi-agent framework to create an open market for Grid services. Second, we have concisely presented key simulation results of our work in progress. The results exhibit the usefulness of our negotiation protocol for realistic scenarios that involves different background traffic loading, message sizes and traffic flow asymmetry between background and negotiation traffics.

  2. Design of a Distributed Personal Information Access Control Scheme for Secure Integrated Payment in NFC

    Directory of Open Access Journals (Sweden)

    Jungho Kang

    2015-06-01

    Full Text Available At the center of core technologies for a future cyber world, such as Internet of Things (IoT or big data, is a context-rich system that offers services by using situational information. The field where context-rich systems were first introduced is near-field communication (NFC-based electronic payments. Near-field Communication (NFC integrated payment services collect the payment information of the credit card and the location information to generate patterns in the user’s consumption or movement through big data technology. Based on such pattern information, tailored services, such as advertisement, are offered to users. However, there is difficulty in controlling access to personal information, as there is a collaborative relationship focused on the trusted service manager (TSM that is close knit to shared personal information. Moreover, in the case of Hadoop, among the many big data analytical technologies, it offers access control functions, but not a way to authorize the processing of personal information, making it impossible to grant authority between service providers to process information. As such, this paper proposes a key generation and distribution method, as well as a secure communication protocol. The analysis has shown that the efficiency was greater for security and performance compared to relation works.

  3. Stability of multiple access network control schemes with carrier sensing and exponential backoff

    Science.gov (United States)

    Barany, Ernest; Krupa, Maciej

    2006-05-01

    A new approach to determine the stability of multiple access network control schemes is presented. A “busy” network (the precise meaning of the term “busy” will be presented in the text) is modelled as a switched single-server hybrid dynamical system whose switching laws are stochastic and are based on typical multiple access network control protocols such as ALOHA and ethernet. The techniques are used to compute the critical ratio of traffic production per network node to total available bandwidth that ensures that data packets will not accumulate unboundedly in waiting queues at each node. This is a measure of stability of the network and is an emergent, global, property determined by decentralized, autonomous behavior of each node. The behavior of each individual node is regarded as “microscopic” and the collective behavior of the network as a whole are emergent consequences of such microscopic laws. The results follow from the stationary distribution property of ergodic Markov chains.

  4. Reducing depressive symptomatology with a smartphone app: study protocol for a randomized, placebo-controlled trial.

    Science.gov (United States)

    Giosan, Cezar; Cobeanu, Oana; Mogoaşe, Cristina; Szentagotai, Aurora; Mureşan, Vlad; Boian, Rareș

    2017-05-12

    weeks. A short therapist check-in via phone will take place every week. Participants in the delayed-intervention condition will be given access to the app after 6 weeks from randomization. The primary outcome is the level of depressive symptomatology. The intervention delivered through the app to the active condition includes psychoeducational materials and exercises based on CBT for depression, while the placebo intervention uses a sham version of the app (i.e., similar structure of courses and exercises). To our knowledge, this study protocol is the first to test the efficacy of a smartphone app for depressive symptomatology in the form of a randomized controlled trial (RCT) that includes an active placebo condition. As such, this can substantially add to the body of evidence supporting the use of apps designed to decrease depression. ClinicalTrials.gov, identifier: NCT03060200 . Registered on 1 February 2017. The first participant was enrolled on 17 February 2017.

  5. 78 FR 51810 - Twenty-Fourth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-08-21

    ... Security Access Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control... RTCA Special Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held...

  6. 76 FR 50811 - Eighth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-08-16

    ... Access Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 224: Airport Security Access Control...

  7. 77 FR 25525 - Thirteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems.

    Science.gov (United States)

    2012-04-30

    ... Access Control Systems. AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems... Committee 224, Airport Security Access Control Systems DATES: The meeting will be held May 30, 2012, from...

  8. Energy-efficient MAC protocols for Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    Li De-liang; Peng Fei

    2009-01-01

    Designing energy-efficient Medium Access Control (MAC) protocols has a significant influence on the energy performance of wireless sensor network (WSN). In this paper we present a survey of the recent typical MAC protocols regarding energy efficiency for WSN. According to channel access policies, we classify these protocols into four categories: contention-based, TDMA-based, hybrid, and cross layer protocols, in which the advantages and disadvantages in each class of MAC protocols are discussed. Finally, we point out open research issues that need to carry on to achieve high energy efficiency for the design of MAC protocols in WSN.

  9. Analisis Performansi VOIP (Voice Over Internet Protocol Pada Jaringan Wimax (Worldwide Interoperability For Microwave Access Di Wilayah DKI Jakarta

    Directory of Open Access Journals (Sweden)

    Widhiatmoko Widhiatmoko

    2011-05-01

    Full Text Available VoIP is a system that uses the Internet network to transmit voice packets from one place to another using IP protocols intermediaries. With VoIP technology can be much cheaper call charges, especially for communicating overseas because of voice and data using the same network ie the Internet network. VoIP is a service that is very susceptible to delay while the existing access network is currently providing a significant delay for VoIP. One alternative network that can be used to overcome these problems is to use WiMAX technology because WiMAX can provide speed data services up to 70 Mbps.From the research,  results of one way delay, jitter and packet loss still at the value recommended by ITU-T, which is the maximum value of one way delay measurement is 159.87 ms, for jitter 7.52 ms and for packet loss is 3.175%. The one way delay and packet loss from the measurement used to find the MOS score which is the value for quality of VoIP. MOS value range obtained from the calculation of 3.6 to 4.2, which means VoIP feasible to apply to the WiMAX network. The maximum value can reach 2.8 Mbps throughput to 0.575 Mbps for downlink and uplink. From the research also found that the SQI values that are above the standard value of the device will provide a high SNR value, and the higher SQI values then its RSSI value is also bigger.

  10. Task-role-based Access Control Model in Smart Health-care System

    Directory of Open Access Journals (Sweden)

    Wang Peng

    2015-01-01

    Full Text Available As the development of computer science and smart health-care technology, there is a trend for patients to enjoy medical care at home. Taking enormous users in the Smart Health-care System into consideration, access control is an important issue. Traditional access control models, discretionary access control, mandatory access control, and role-based access control, do not properly reflect the characteristics of Smart Health-care System. This paper proposes an advanced access control model for the medical health-care environment, task-role-based access control model, which overcomes the disadvantages of traditional access control models. The task-role-based access control (T-RBAC model introduces a task concept, dividing tasks into four categories. It also supports supervision role hierarchy. T-RBAC is a proper access control model for Smart Health-care System, and it improves the management of access rights. This paper also proposes an implementation of T-RBAC, a binary two-key-lock pair access control scheme using prime factorization.

  11. Studying the Noise Control Engineering Protocols in Industry

    Directory of Open Access Journals (Sweden)

    Hamid Golshah

    1999-03-01

    Full Text Available Today, sound is one of the detrimental factors in the workplace and its harmful impact has been so important that scientists have named it “Noise Pollutions”. Hearing is one of the five senses of human being which is also a medium for communicating with other s and enjoying the pleasant feeling of listening to a piece of music. In spite of this, changes in the intensity and frequency of sound can make it annoying. Using Sound Level Meter to measure the dB of noise in the workplace and noise control principles will be discussed here.

  12. APC-MAC/TA: Adaptive Power Controlled MAC Protocol with Traffic Awareness for Wireless Sensor Networks

    Science.gov (United States)

    Woo, Seok; Kim, Kiseon

    In this paper, we propose an adaptive power controlled MAC protocol with a traffic-aware scheme specifically designed to reduce both energy and latency in wireless sensor networks. Typically, existing MAC protocols for sensor networks sacrifice latency performance for node energy efficiency. However, some sensor applications for emergencies require rather fast transmissions of sensed data, where we need to consider both energy and latency together. The proposed MAC protocol includes two novel ideas: one is a transmission power control scheme for improving latency in high traffic loads, and the other is a traffic-aware scheme to save more energy in low traffic loads. The transmission power control scheme increases channel utilization by mitigating interference between nodes, and the traffic-aware scheme allows nodes to sleep to reduce idle energy consumption when there are no traffic loads in a network. Simulation results show that the proposed protocol significantly reduces the latency as well as the energy consumption compared to the S-MAC protocol specifically for a large transmission power of nodes and low network traffic.

  13. A new communication protocol family for a distributed spacecraft control system

    Science.gov (United States)

    Baldi, Andrea; Pace, Marco

    1994-01-01

    In this paper we describe the concepts behind and architecture of a communication protocol family, which was designed to fulfill the communication requirements of ESOC's new distributed spacecraft control system SCOS 2. A distributed spacecraft control system needs a data delivery subsystem to be used for telemetry (TLM) distribution, telecommand (TLC) dispatch and inter-application communication, characterized by the following properties: reliability, so that any operational workstation is guaranteed to receive the data it needs to accomplish its role; efficiency, so that the telemetry distribution, even for missions with high telemetry rates, does not cause a degradation of the overall control system performance; scalability, so that the network is not the bottleneck both in terms of bandwidth and reconfiguration; flexibility, so that it can be efficiently used in many different situations. The new protocol family which satisfies the above requirements is built on top of widely used communication protocols (UDP and TCP), provides reliable point-to-point and broadcast communication (UDP+) and is implemented in C++. Reliability is achieved using a retransmission mechanism based on a sequence numbering scheme. Such a scheme allows to have cost-effective performances compared to the traditional protocols, because retransmission is only triggered by applications which explicitly need reliability. This flexibility enables applications with different profiles to take advantage of the available protocols, so that the best rate between sped and reliability can be achieved case by case.

  14. Implementation of ON/OFF and PID controller using TCP Protocol Based on Virtual Instrumentation

    Directory of Open Access Journals (Sweden)

    Abhyarthana Bisoyi , Umesh Chandra Pati

    2013-03-01

    Full Text Available LabVIEW(Laboratory Virtual InstrumentEngineering Workbenchisthe softwarewhichgives virtual existence ofhardware, reduces its costand hencetermed as Virtual Instrumentation.Thispaper deals with the implementation ofON/OFFand PID controller for controlling the temperatureof a heating element inside a wooden box with thehelp of LabVIEW. In this software,TransmissionControl Protocol (TCPis used for developing anonline transmission processbetween client andserver. Client has control overthe set point andServer has control over the temperature. Inhardware section, a DataAcquisition (DAQ cardreads temperature from sensor and delivers toServer. With the help of internet protocol,clientprovides the value ofset point according to whichthe control actions aretaken by the server.Thepaper also includes discussions regarding theadvantages and disadvantages of TCP/IP.

  15. Access Control in Decentralised Publish/Subscribe Systems

    Directory of Open Access Journals (Sweden)

    Lauri I.W. Pesonen

    2007-04-01

    Full Text Available Publish/subscribe has emerged as an attractive communication paradigm for building Internet-wide distributed systems by decoupling message senders from receivers. Large scale publish/subscribe systems are likely to employ components of the event transport network owned by cooperating, but independent organisations. As the number of participants in the network increases, security becomes an increasing concern. So far most of the research on publish/subscribe has focused on efficient event routing, event filtering, and composite event detection. Very little research has been published regarding securing publish/subscribe systems. This paper extends our previous work to present and evaluate a secure multi-domain publish/subscribe infrastructure that supports and enforces fine-grained access control over the individual attributes of event types.

  16. Database Security System for Applying Sophisticated Access Control via Database Firewall Server

    OpenAIRE

    Eun-Ae Cho; Chang-Joo Moon; Dae-Ha Park; Kang-Bin Yim

    2014-01-01

    Database security, privacy, access control, database firewall, data break masking Recently, information leakage incidents have occurred due to database security vulnerabilities. The administrators in the traditional database access control methods grant simple permissions to users for accessing database objects. Even though they tried to apply more strict permissions in recent database systems, it was difficult to properly adopt sophisticated access control policies to commercial databases...

  17. Streamlining tasks and roles to expand treatment and care for HIV: randomised controlled trial protocol

    Directory of Open Access Journals (Sweden)

    van Vuuren Cloete

    2008-04-01

    Full Text Available Abstract Background A major barrier to accessing free government-provided antiretroviral treatment (ART in South Africa is the shortage of suitably skilled health professionals. Current South African guidelines recommend that only doctors should prescribe ART, even though most primary care is provided by nurses. We have developed an effective method of educational outreach to primary care nurses in South Africa. Evidence is needed as to whether primary care nurses, with suitable training and managerial support, can initiate and continue to prescribe and monitor ART in the majority of ART-eligible adults. Methods/design This is a protocol for a pragmatic cluster randomised trial to evaluate the effectiveness of a complex intervention based on and supporting nurse-led antiretroviral treatment (ART for South African patients with HIV/AIDS, compared to current practice in which doctors are responsible for initiating ART and continuing prescribing. We will randomly allocate 31 primary care clinics in the Free State province to nurse-led or doctor-led ART. Two groups of patients aged 16 years and over will be included: a 7400 registering with the programme with CD4 counts of ≤ 350 cells/mL (mainly to evaluate treatment initiation and b 4900 already receiving ART (to evaluate ongoing treatment and monitoring. The primary outcomes will be time to death (in the first group and viral suppression (in the second group. Patients' survival, viral load and health status indicators will be measured at least 6-monthly for at least one year and up to 2 years, using an existing province-wide clinical database linked to the national death register. Trial registration Controlled Clinical Trials ISRCTN46836853

  18. Congestion Control Protocol for Wireless Sensor Networks Handling Prioritized Heterogeneous Traffic

    CERN Document Server

    Monowar, Muhammad Mostafa; Pathan, Al-Sakib Khan; Hong, Choong Seon

    2008-01-01

    Heterogeneous applications could be assimilated within the same wireless sensor network with the aid of modern motes that have multiple sensor boards on a single radio board. Different types of data generated from such types of motes might have different transmission characteristics in terms of priority, transmission rate, required bandwidth, tolerable packet loss, delay demands etc. Considering a sensor network consisting of such multi-purpose nodes, in this paper we propose Prioritized Heterogeneous Traffic-oriented Congestion Control Protocol (PHTCCP) which ensures efficient rate control for prioritized heterogeneous traffic. Our protocol uses intra-queue and inter-queue priorities for ensuring feasible transmission rates of heterogeneous data. It also guarantees efficient link utilization by using dynamic transmission rate adjustment. Detailed analysis and simulation results are presented along with the description of our protocol to demonstrate its effectiveness in handling prioritized heterogeneous traf...

  19. Case-control study on analgesics and nephropathy (SAN: protocol

    Directory of Open Access Journals (Sweden)

    van der Woude Fokko

    2005-08-01

    Full Text Available Abstract Background The association between intake of non-phenacetin-containing analgesics and the occurrence of chronic renal failure is still controversially discussed. A new epidemiologic study was planned and conducted in Germany and Austria. Methods/design The objective of the international, multicenter case-control study was to evaluate the association between end-stage renal disease (ESRD and use of non-phenacetin-containing analgesics with particular emphasis on combined formulations. A targeted sample of 1000 new (incident dialysis patients, aged less than 50 years, was planned to recruit between January 1, 2001 and December 31, 2004. The age limit was chosen to avoid contamination of the study population with phenacetin-containing analgesics to the extent possible. Four control subjects per ESRD case, matched by age, sex, and region were selected from the population living in the region the case came from. Lifetime exposure to analgesics and potential renal risk factors were recorded in a single face-to-face interview. A set of aids was introduced to reinforce the memory of study participants. A standardized, pre-tested interview questionnaire (participants, a medical documentation sheet (physicians in dialysis centres, a logbook for all activities (dialysis centres were used to collect the necessary data. Quality management consisted of the standardized procedures, (re- training and supervision of interviewers, regular checks of all incoming data for completeness and plausibility. The study is scientifically independent and governed by a international Scientific Advisory Committee that bridged the gap between the sponsoring companies and the investigators. Also other advisory groups assisted the managing committee of the study. All relevant German and Austrian nephrological associations supported the study, and the study design was carefully reviewed and approved by the Kidney Foundation of Germany. Discussion The study is expected to

  20. Safety systems and access control in the National Ignition Facility.

    Science.gov (United States)

    Reed, Robert K; Bell, Jayce C

    2013-06-01

    The National Ignition Facility (NIF) is the world's largest and most energetic laser system. The facility has the potential to generate ionizing radiation due to the interaction between the laser beams and target material, with neutrons and gamma rays being produced during deuterium-tritium fusion reactions. To perform these experiments, several types of hazards must be mitigated and controlled to ensure personnel safety. NIF uses a real-time safety system to monitor and mitigate the hazards presented by the facility. The NIF facility Safety Interlock System (SIS) monitors for oxygen deficiency and controls access to the facility preventing exposure to laser light and radiation from the Radiation Generating Devices. It also interfaces to radiation monitoring and other radiological monitoring and alarm systems. The SIS controls permissives to the hazard-generating equipment and annunciates hazard levels in the facility. To do this reliably and safely, the SIS has been designed as a fail-safe system with a proven performance record now spanning over 10 y. This paper discusses the SIS, its design, implementation, operator interfaces, validation/verification, and the hazard mitigation approaches employed in the NIF. A brief discussion of the Failure Modes and Effect Analysis supporting the SIS will also be presented. The paper ends with a general discussion of SIS do's and don'ts and common design flaws that should be avoided in SIS design.

  1. Dynamic Postural Control in Female Athletes and Nonathletes After a Whole-Body Fatigue Protocol.

    Science.gov (United States)

    Baghbani, Fatemeh; Woodhouse, Linda J; Gaeini, Abbas A

    2016-07-01

    Baghbani, F, Woodhouse, LJ, and Gaeini, AA. Dynamic postural control in female athletes and nonathletes after a whole-body fatigue protocol. J Strength Cond Res 30(7): 1942-1947, 2016-Postural control is a crucial element in regular training of athletes, development of complex technical movement, and injury prevention; however, distributing factor of the postural control such as fatigue has been neglected by athletic trainers in novice and inexperienced athletes. The objective of this study was to compare changes in dynamic postural control of young female athletes and nonathletes after a fatigue protocol. Thirty females (15 athletes and 15 nonathletes) with no orthopedic problems were recruited to participate in this study. All participants completed the pre-SEBT (star excursion balance test) in 8 directions at baseline; then, they performed a 20-minute fatigue protocol after which post-SEBT was measured. Rating of perceived exertion was measured using the Borg scale immediately before, mid-way through (i.e., after the third station), and after performing the fatigue protocol (i.e., immediately before the post-SEBT). Female nonathlete groups had significant differences in dynamic balance performance after fatigue in the medial, posteromedial, and posterior directions (p postural control of the novice with progressing the exercise time. Our findings could also help coaches to develop trainings focused on the 3 directions of medial, posteromedial, and posterior directions and aimed at exercises increasing fatigue resistance.

  2. User Driven Feedback Control System driven using CAN Protocol

    Directory of Open Access Journals (Sweden)

    Ankita Goyal

    2013-09-01

    Full Text Available -Industrial automation is a sector having vast possibilities for major improvements. The system described in this paper consists of a console master computer (CMC which will monitor various physical nodes usually found in a large industry. The proposed work analyzes the capability of CAN networking which includes data traffic management. The CMC is designed using MATLAB 7.12; the CAN networking is supported using the Vehicular Network Toolbox. The proposed system using CAN has the advantages of being simple in its design which contributes to the overall low cost. The novelty of the work lies in the low cost approach, and fails safe methodology of CAN communication. The proposed system is capable of sending and receiving signals with the additional benefit of feedback mechanism .The proposed work is implementable in any industry with the cost advantage of CAN interface. The proposed work can be used as a cheaper and robust alternative to native technologies like PLC (Programmable Logic Controller. Moreover, the CAN network system is immune from the electrical interferences.

  3. Genomic Control of Retinal Cell Number: Challenges, Protocol, and Results.

    Science.gov (United States)

    Keeley, Patrick W; Whitney, Irene E; Reese, Benjamin E

    2017-01-01

    This chapter considers some of the challenges in obtaining accurate and consistent estimates of neuronal population size in the mouse retina, in order to identify the genetic control of cell number through QTL mapping and candidate gene analysis. We first discuss a variety of best practices for analyzing large numbers of recombinant inbred strains of mice over the course of a year in order to amass a satisfactory dataset for QTL mapping. We then consider the relative merits of using average cell density versus estimated total cell number as the target trait to be assessed, and why estimates of heritability may differ for these two traits when studying the retina in whole-mount preparations. Using our dataset on cell number for 12 different retinal cell types across the AXB/BXA recombinant inbred strain set as an example, we briefly review the QTL identified and their relationship to one another. Finally, we discuss our strategies for parsing QTL in order to identify prospective candidate genes, and how those candidates may in turn be dissected to identify causal regulatory or coding variants. By identifying the genetic determinants of nerve cell number in this fashion, we can then explore their roles in modulating developmental processes that underlie the formation of the retinal architecture.

  4. Precision Time Protocol support hardware for ATCA control and data acquisition system

    Energy Technology Data Exchange (ETDEWEB)

    Correia, Miguel, E-mail: miguelfc@ipfn.ist.utl.pt [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Sousa, Jorge; Carvalho, Bernardo B.; Santos, Bruno; Carvalho, Paulo F.; Rodrigues, António P.; Combo, Álvaro M.; Pereira, Rita C. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Correia, Carlos M.B.A. [Centro de Instrumentação, Departamento de Física, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Gonçalves, Bruno [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal)

    2015-10-15

    Highlights: • ATCA based control and data acquisition subsystem has been developed at IPFN. • PTP and time stamping were implemented with VHDL and PTP daemon (PTPd) codes. • The RTM (…) provides PTP synchronization with an external GMC. • The main advantage is that timestamps are generated closer to the Physical Layer at the GMII. • IPFN's upgrade consistently exhibited jitter values below 25 ns RMS. - Abstract: An in-house, Advanced Telecom Computing Architecture (ATCA) based control and data acquisition (C&DAQ) subsystem has been developed at Instituto de Plasmas e Fusão Nuclear (IPFN), aiming for compliance with the ITER Fast Plant System Controller (FPSC). Timing and synchronization for the ATCA modules connects to ITER Control, Data Access and Communication (CODAC) through the Timing Communication Network (TCN), which uses IEEE 1588-2008 Precision Time Protocol (PTP) to synchronize devices to a Grand Master Clock (GMC). The TCN infrastructure was tested for an RMS jitter under the limit of 50 ns. Therefore, IPFN's hardware, namely the ATCA-PTSW-AMC4 hub-module, which is in charge of timing and synchronization distribution for all subsystem endpoints, shall also perform within this jitter limit. This paper describes a relevant upgrade, applied to the ATCA-PTSW-AMC4 hardware, to comply with these requirements – in particular, the integration of an add-on module “RMC-TMG-1588” on its Rear Transition Module (RTM). This add-on is based on a commercial FPGA-based module from Trenz Electronic, using the ZHAW “PTP VHDL code for timestamping unit and clock”, which features clock offset and drift correction and hardware-assisted time stamping. The main advantage is that timestamps are generated closer to the Physical Layer, at the Gigabit Ethernet Media Independent Interface (GMII), avoiding the timing uncertainties accumulated through the upper layers. PTP code and user software run in a MicroBlaze™ soft-core CPU with Linux in the

  5. Acupuncture for dry eye: a randomised controlled trial protocol

    Directory of Open Access Journals (Sweden)

    Kim Ae-Ran

    2009-12-01

    Full Text Available Abstract Background Dry eye is usually managed by conventional medical interventions such as artificial tears, anti-inflammatory drugs and surgical treatment. However, since dry eye is one of the most frequent ophthalmologic disorders, safer and more effective methods for its treatment are necessary, especially for vulnerable patients. Acupuncture has been widely used to treat patients with dry eye. Our aim is to evaluate the effectiveness and safety of acupuncture for this condition. Methods/Design A randomised, patient-assessor blinded, sham (non-acupuncture point, shallow acupuncture controlled study was established. Participants allocated to verum acupuncture and sham acupuncture groups will be treated three times weekly for three weeks for a total of nine sessions per participant. Seventeen points (GV23; bilateral BL2, GB4, TE23, Ex1 (Taiyang, ST1 and GB20; and left SP3, LU9, LU10 and HT8 for men, right for women have been selected for the verum acupuncture; for the sham acupuncture, points have been selected that do not coincide with a classical acupuncture point and that are located close to the verum points, except in the case of the rim of the eye. Ocular surface disease index, tear film breakup time, the Schirmer I test, medication quantification scale and general assessment of improvement will be used as outcome variables for evaluating the effectiveness of acupuncture. Safety will also be assessed at every visit. Primary and secondary outcomes will be assessed four weeks after screening. All statistical analyses will be performed using analysis of covariance. Discussion The results of this trial will be used as a basis for clarifying the efficacy of acupuncture for dry eye. Trial registration ClinicalTrials.gov NCT00969280.

  6. A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems.

    Science.gov (United States)

    Choi, Donghee; Kim, Dohoon; Park, Seog

    2015-01-01

    Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment.

  7. Glycemic control in cardiac surgery: implementing an evidence-based insulin infusion protocol.

    Science.gov (United States)

    Hargraves, Joelle D

    2014-05-01

    Acute hyperglycemia following cardiac surgery increases the risk of deep sternal wound infection, significant early morbidity, and mortality. Insulin infusion protocols that target tight glycemic control to treat hyperglycemia have been linked to hypoglycemia and increased mortality. Recently published studies examining glycemic control in critical illness and clinical practice guidelines from professional organizations support moderate glycemic control. To measure critical care nurses' knowledge of glycemic control in cardiac surgery before and after education. To evaluate the safety and effectiveness of an evidence-based insulin infusion protocol targeting moderate glycemic control in cardiac surgery patients. This evidence-based practice change was implemented in the cardiovascular unit in a community teaching hospital. Nurses completed a self-developed questionnaire to measure knowledge of glycemic control. Blood glucose data, collected (retrospectively) from anesthesia end time through 11:59 PM on postoperative day 2, were compared from 2 months before to 2 months after the practice change. Nurses' knowledge (test scores) increased significantly after education (pretest mean = 53.10, SD = 11.75; posttest mean = 79.10, SD = 12.02; t54 = -8.18, P nurses' knowledge of glycemic control and implementing an insulin infusion protocol targeting moderate glycemic control were effective for treating acute hyperglycemia following cardiac surgery with decreased incidence of hypoglycemia.

  8. 78 FR 31627 - Twenty-Second Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-05-24

    ...: RTCA Special Committee 224, Airport Security Access Control Systems AGENCY: Federal Aviation... 224, Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of the twenty-second meeting of the RTCA Special Committee 224, Airport Security Access...

  9. 76 FR 9632 - Fifth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-02-18

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Access Control Systems (Update to DO-230B): Agenda March 10, 2011 Welcome/Introductions/Administrative... Federal Aviation Administration Fifth Meeting: RTCA Special Committee 224: Airport Security Access...

  10. Telerehabilitation Versus Traditional Care Following Total Hip Replacement: A Randomized Controlled Trial Protocol

    Science.gov (United States)

    Bourke, Michael; Crossley, Kay; Russell, Trevor

    2017-01-01

    Background Total hip replacement (THR) is the gold standard treatment for severe hip osteoarthritis. Effectiveness of physical rehabilitation for THR patients following discharge from hospital is supported by evidence; however, barriers such as geographical location and transport can limit access to appropriate health care. One solution to this issue is using an alternative model of care using telerehabilitation technology to deliver rehabilitation programs directly into patients’ homes. A telerehabilitation model may also have potential health care cost savings for health care providers. Objective This study aims to determine if a telerehabilitation model of care delivered remotely is as effective as face-to-face rehabilitation in the THR population and cost effective for health care providers and patients. Methods A total of 70 people undergoing THR will be recruited to participate in a randomized, single-blind, controlled noninferiority clinical trial. The trial will compare a technology-based THR rehabilitation program to in-person care. On discharge from hospital, participants randomized to the in-person group will receive usual care, defined as a paper home exercise program (HEP) targeting strengthening exercises for quadriceps, hip abductors, extensors, and flexors; they will be advised to perform their HEP 3 times per day. At 2, 4, and 6 weeks postoperatively, they will receive a 30-minute in-person physiotherapy session with a focus on gait retraining and reviewing and progressing their HEP. The telerehabilitation protocol will involve a program similar in content to the in-person rehabilitation program, except delivery will be directly into the homes of the participants via telerehabilitation technology on an iPad. Outcomes will be evaluated preoperatively, day of discharge from in-patient physiotherapy, 6 weeks and 6 months postoperatively. The primary outcome will be the quality of life subscale of the hip disability and osteoarthritis outcome score

  11. Multi-tag content access control in RFID system

    OpenAIRE

    2010-01-01

    Radio Frequency Identification (RFID) makes great flexibility and high efficiency for data acquisition in industry and daily life. At the other side, it brings the privacy risks and multiple tags collision issue. Current research in RFID system focuses on the security and privacy issue which is based on authentication protocols between a tag and a Reader. There is a need to design a reasonable protocol which takes care of both multi-tag anti-collision and security issue. This thesis presen...

  12. Suction catheter for enhanced control and accuracy of transseptal access.

    Science.gov (United States)

    Sulkin, Matthew S; Berwick, Zachary C; Hermiller, James B; Navia, Jose A; Kassab, Ghassan S

    2016-12-20

    Percutaneous structural heart therapies, such as mitral value repair, require site-specific transseptal access (TSA). This can be challenging for interventional cardiologists. We describe a TSA catheter (TSAC) that utilises suction for enhanced control and puncture accuracy. Here, we aim to evaluate the safety and efficacy of the device. Ex vivo interatrial septum preparations were dissected from swine (n=8) and diseased human hearts (n=6) to quantify TSAC suction and needle puncture force. TSAC suction was 6.5-fold greater than the opposing needle puncture force, and thus provides sufficient stabilisation for punctures. The safety and efficacy of TSAC was evaluated in a chronic mitral regurgitation swine model (n=10) and compared to a conventional TSA device. MR was induced by disrupting one to three mitral chordae tendineae, and the progression of heart disease was followed for three weeks. During device testing, procedure time and fluoroscopy exposure were not statistically different between devices. TSAC reduced septal displacement from 8.7±0.30 mm to 3.60±0.19 mm (p<0.05) and improved puncture accuracy 1.75-fold. TSAC provides controlled TSA and improves puncture accuracy, while maintaining procedure time and workflow. These findings provide a strong rationale for a first-in-man study to demonstrate the clinical utility of the device.

  13. Brief intervention to reduce risky drinking in pregnancy: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Wilson Graeme B

    2012-09-01

    Full Text Available Abstract Background Risky drinking in pregnancy by UK women is likely to result in many alcohol-exposed pregnancies. Studies from the USA suggest that brief intervention has promise for alcohol risk reduction in antenatal care. However, further research is needed to establish whether this evidence from the USA is applicable to the UK. This pilot study aims to investigate whether pregnant women can be recruited and retained in a randomized controlled trial of brief intervention aimed at reducing risky drinking in women receiving antenatal care. Methods The trial will rehearse the parallel-group, non-blinded design and procedures of a subsequent definitive trial. Over 8 months, women aged 18 years and over (target number 2,742 attending their booking appointment with a community midwife (n = 31 in north-east England will be screened for alcohol consumption using the consumption questions of the Alcohol Use Disorders Identification Test (AUDIT-C. Those screening positive, without a history of substance use or alcohol dependence, with no pregnancy complication, and able to give informed consent, will be invited to participate in the trial (target number 120. Midwives will be randomized in a 1:1 ratio to deliver either treatment as usual (control or structured brief advice and referral for a 20-minute motivational interviewing session with an alcohol health worker (intervention. As well as demographic and health information, baseline measures will include two 7-day time line follow-back questionnaires and the EuroQoL EQ-5D-3 L questionnaire. Measures will be repeated in telephone follow-ups in the third trimester and at 6 months post-partum, when a questionnaire on use of National Health Service and social care resources will also be completed. Information on pregnancy outcomes and stillbirths will be accessed from central health service records before the follow-ups. Primary outcomes will be rates of eligibility, recruitment, intervention

  14. A Priority Protocol for Token-Ring Networks

    Science.gov (United States)

    Liu, H. T.

    1986-01-01

    New priority protocol controls access to token-ring local-area network (LAN) of digital-communication stations over widely ranging mix of low- and high-priority traffic. Protocol, called round-robin priority scheme (RRPS), introduces only small overhead and therefore degrades system performance only minimally. Key messages guaranteed access to local-area network during peak loads.

  15. Impact of Transport Control Protocol on Full Duplex Performance in 5G Networks

    DEFF Research Database (Denmark)

    Gatnau, Marta; Berardinelli, Gilberto; Mahmood, Nurul Huda

    2016-01-01

    Full duplex (FD) communication has attracted the attention of the industry and the academia as an important feature in the design of the future 5th generation (5G) wireless communication system. Such technology allows a device to simultaneously transmit and receive in the same frequency band......, with the potential of providing higher throughput and lower latency compared to traditional half duplex (HD) systems. In this paper, the interaction between Transport Control Protocol (TCP) and FD in 5G ultra-dense small cell networks is studied. TCP is a well-known transport layer protocol for providing reliability...

  16. The Active for Life Year 5 (AFLY5) school-based cluster randomised controlled trial protocol: detailed statistical analysis plan.

    Science.gov (United States)

    Lawlor, Debbie A; Peters, Tim J; Howe, Laura D; Noble, Sian M; Kipping, Ruth R; Jago, Russell

    2013-07-24

    The Active For Life Year 5 (AFLY5) randomised controlled trial protocol was published in this journal in 2011. It provided a summary analysis plan. This publication is an update of that protocol and provides a detailed analysis plan. This update provides a detailed analysis plan of the effectiveness and cost-effectiveness of the AFLY5 intervention. The plan includes details of how variables will be quality control checked and the criteria used to define derived variables. Details of four key analyses are provided: (a) effectiveness analysis 1 (the effect of the AFLY5 intervention on primary and secondary outcomes at the end of the school year in which the intervention is delivered); (b) mediation analyses (secondary analyses examining the extent to which any effects of the intervention are mediated via self-efficacy, parental support and knowledge, through which the intervention is theoretically believed to act); (c) effectiveness analysis 2 (the effect of the AFLY5 intervention on primary and secondary outcomes 12 months after the end of the intervention) and (d) cost effectiveness analysis (the cost-effectiveness of the AFLY5 intervention). The details include how the intention to treat and per-protocol analyses were defined and planned sensitivity analyses for dealing with missing data. A set of dummy tables are provided in Additional file 1. This detailed analysis plan was written prior to any analyst having access to any data and was approved by the AFLY5 Trial Steering Committee. Its publication will ensure that analyses are in accordance with an a priori plan related to the trial objectives and not driven by knowledge of the data. ISRCTN50133740.

  17. Efficacy of Acute Pain Control Protocol in Triage Department on Analgesics Administration Time and Patients' Satisfaction

    Directory of Open Access Journals (Sweden)

    Seyedhossein Seyyedhoseini Davaraani

    2014-07-01

    Full Text Available Objective: Current study was conducted to develop a pain control protocol by Morphine Sulfate (MS Suppository in triage ward with the main primary outcomes of first analgesic administration time, patients' satisfaction and also the changes in pain intensity. Methods: In this randomized clinical trial, 318 consecutive patients attending to an academic tertiary health care center in Tehran, Iran in 2011 and 2012 were enrolled. The patients were randomly assigned to receive either routine pain control by emergency medicine residents in emergency department (n=132 or pain control protocol in triage level by nurses (n=186. Those with pain in control group were treated with conventional pain control program and those in intervention group with pain intensities higher than four were treated with suppository stat 10 mg dose of MS administered by nurses in triage ward. Results: The mean change in pain intensity was significantly (P<0.0001 higher in intervention group (4.2 versus 0.2 and the first analgesic administration time was significantly different between groups (P<0.05 being less in the intervention group (43.1 versus 4.6. Also the patients' satisfaction was significantly higher in the intervention group (P<0.0001. No drug adverse effects were seen. Conclusions: Totally, according to the obtained results, it may be concluded that acute pain control protocol in triage department by suppository of MS would result in reduced analgesics administration time and higher patients' satisfaction.   Keywords: Analgesia; Emergency Department; Pain Control

  18. Stream Control Transmission Protocol as a Transport for SIP: a case study

    Directory of Open Access Journals (Sweden)

    Giuseppe De Marco

    2004-06-01

    Full Text Available The dominant signalling protocol both in future wireless and wired networks will be the Session Initiation Protocol (SIP, as pointed out in the 3G IP-based mobile networks specifications, entailing a fully Internet integrated network. The use of SIP in the IP Multimedia Subsytem (IMS of Release 5 involves the development of servers capable to handle a large number of call requests. The signaling traffic associated to such requests could explode, if an intelligent congestion control were not introduced. Stream Control Transmission Protocol (SCTP was born to support transport of SS7 signaling messages. However, many of the SCTP features are also useful for transport of SIP messages, as: congestion control mechanism, good separation among independent messages, multihoming. Indeed, adoption of SCTP as transport of SIP signaling might prove useful in some situations where usual transport protocols, like TCP and UDP, suffer performance degradation. In this paper, we analyse the general framework wherein SIP operates and we discuss the benefits of using SCTP as a transport for SIP, toward fair sharing of network resources. This study is carried on in the context of the implementation of an high-performance SIP Proxy Server. We also present some preliminar results of an implementation of SIP over SCTP/UDP in a real LAN environment.

  19. Data Access, Ownership, and Control: Toward Empirical Studies of Access Practices.

    Science.gov (United States)

    Hilgartner, Stephen; Brandt-Rauf, Sherry I.

    1994-01-01

    Examines how the new sociology of science can approach data access issues. A perspective is developed based on an analysis of the process of scientific production, data streams, and intellectual policy issues. (Contains 55 references.) (JLB)

  20. Protocol of an expertise based randomized trial comparing surgical Venae Sectio versus radiological Puncture of Vena Subclavia for insertion of Totally Implantable Access Port in oncological patients

    Directory of Open Access Journals (Sweden)

    Radeleff Boris

    2008-10-01

    Full Text Available Abstract Background Totally Implantable Access Ports (TIAP are being extensively used world-wide and can be expected to gain further importance with the introduction of new neoadjuvant and adjuvant treatments in oncology. Two different techniques for the implantation can be selected: A direct puncture of a central vein and the utilization of a Seldinger device or the surgical Venae sectio. It is still unclear which technique has the optimal benefit/risk ratio for the patient. Design A single-center, expertise based randomized, controlled superiority trial to compare two different TIAP implantation techniques. 100 patients will be included and randomized pre-operatively. All patients aged 18 years or older scheduled for primary elective implantation of a TIAP under local anesthesia who signed the informed consent will be included. The primary endpoint is the primary success rate of the randomized technique. Control Intervention: Venae Sectio will be employed to insert a TIAP by a surgeon; Experimental intervention: Punction of V. Subclavia will be used to place a TIAP by a radiologist. Duration of study: Approximately 10 months, follow up time: 90 days. Organisation/Responsibility The PORTAS 2 – Trial will be conducted in accordance with the protocol and in compliance with the moral, ethical, and scientific principles governing clinical research as set out in the Declaration of Helsinki (1989 and Good Clinical Practice (GCP. The Center of Clinical Trials at the Department of Surgery, University Hospital Heidelberg is responsible for design and conduct of the trial including randomization and documentation of patients' data. Data management and statistical analysis will be performed by the independent Institute for Medical Biometry and Informatics (IMBI, University of Heidelberg. Trial Registration The trial is registered at ClinicalTrials.gov (NCT00600444.

  1. A Message Exchange Protocol in Command and Control Systems Integration, using the JC3IEDM

    Science.gov (United States)

    2014-06-01

    19TH International Command and Control Research and Technology Symposium C2 Agility: Lessons Learned from Research and Operations. A Message...overhead during packets reading. The service-oriented architecture (SOA) with the use of Web Services technology was chosen because of ease of learning ... Enviroments . IEEE Communications Magazine (Feb. 1997), 46-55. A Message Exchange Protocol in Command and Control Systems Integration, using the

  2. [Donation protocol following controlled cardiac death (Maastricht type III donation). First experience].

    Science.gov (United States)

    Rubio-Muñoz, J J; Pérez-Redondo, M; Alcántara-Carmona, S; Lipperheide-Vallhonrat, I; Fernández-Simón, I; Valdivia-de la Fuente, M; Villanueva-Fernández, H; Balandín-Moreno, B; Ortega-López, A; Romera-Ortega, M A; Galdos-Anuncibay, P

    2014-03-01

    To present our experience with the implementation of a donation protocol following controlled cardiac death (Maastricht type III donation). A retrospective descriptive and observational study was made. Intensive Care Unit of a third-level university hospital. Eight patients in an irreversible state, in which withdrawal of all life support had been agreed, were evaluated as potential donors. Application of the adopted protocol. Clinical data of donors, evaluation of a donation protocol following cardiac death, warm ischemia times, and short-term outcome of the recipients. Eight patients were evaluated. In one case donation was not possible because no cardiac arrest developed in the 120 minutes after extubation. The 7 remaining patients were effective kidney donors. Warm ischemia times were less than 23 minutes in all cases. Although 7 of the 14 recipients suffered delayed graft function, all of them achieved good renal function. Donation after cardiac death in patients in an overwhelming and irreversible state represents a potential source of donors not previously considered in this country. The prior development of a consensus-based protocol can help increase the number of organs in combination with those obtained after brain death. In our experience, the results of kidney transplants obtained from donors after cardiac death are good, and the success of these types of protocols could be extended to other organs such as the liver and lungs. Copyright © 2012 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  3. Adaptation of mobile ad-hoc network protocols for sensor networks to vehicle control applications

    Science.gov (United States)

    Sato, Kenya; Matsui, Yosuke; Koita, Takahiro

    2005-12-01

    As sensor network applications to monitor and control the physical environment from remote locations, a mobile ad-hoc network (MANET) has been the focus of many recent research and development efforts. A MANET, autonomous system of mobile hosts, is characterized by multi-hop wireless links, absence of any cellular infrastructure, and frequent host mobility. Many kinds of routing protocols for ad-hoc network have been proposed and still actively updated, because each application has different characteristics and requirements. Since the current studies show it is almost impossible to design an efficient routing protocol to be adapted for all kinds of applications. We, therefore, have focused a certain application, inter-vehicle communication for ITS (Intelligent Transport Systems), to evaluate the routing protocols. In our experiment, we defined several traffic flow models for inter-vehicle communication applications. By using simulation, we evaluated end-to-end delay and throughput performance of data transmission for inter-vehicle communications with the existing routing protocols. The result confirms the feasibility of using some routing protocols for inter-vehicle communication services.

  4. The new biometric access control system resembles a big electronic eye. It will be used to control access to the LHC from 2007 onwards.

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The new LHC access control systems will soon be using the latest technology: optical recognition based on iris image data. In order to gain access to the tunnel it will be your eye, not your credentials that you'll be required to show! As of September, the entrance point at Point 8 should be the first to be fitted out with iris recognition equipment. The other access shafts will then gradually be equipped one by one.

  5. How Drug Control Policy and Practice Undermine Access to Controlled Medicines

    Science.gov (United States)

    Csete, Joanne; Wilson, Duncan; Fox, Edward; Wolfe, Daniel; Rasanathan, Jennifer J. K.

    2017-01-01

    Abstract Drug conventions serve as the cornerstone for domestic drug laws and impose a dual obligation upon states to prevent the misuse of controlled substances while ensuring their adequate availability for medical and scientific purposes. Despite the mandate that these obligations be enforced equally, the dominant paradigm enshrined in the drug conventions is an enforcement-heavy criminal justice response to controlled substances that prohibits and penalizes their misuse. Prioritizing restrictive control is to the detriment of ensuring adequate availability of and access to controlled medicines, thereby violating the rights of people who need them. This paper argues that the drug conventions’ prioritization of criminal justice measures—including efforts to prevent non-medical use of controlled substances—undermines access to medicines and infringes upon the right to health and the right to enjoy the benefits of scientific progress. While the effects of criminalization under drug policy limit the right to health in multiple ways, we draw on research and documented examples to highlight the impact of drug control and criminalization on access to medicines. The prioritization and protection of human rights—specifically the right to health and the right to enjoy the benefits of scientific progress—are critical to rebalancing drug policy. PMID:28630556

  6. Principles of Eliminating Access Control Lists within a Domain

    Directory of Open Access Journals (Sweden)

    Vic Grout

    2012-04-01

    Full Text Available The infrastructure of large networks is broken down into areas that have a common security policy called a domain. Security within a domain is commonly implemented at all nodes. However this can have a negative effect on performance since it introduces a delay associated with packet filtering. When Access Control Lists (ACLs are used within a router for this purpose then a significant overhead is introduced associated with this process. It is likely that identical checks are made at multiple points within a domain prior to a packet reaching its destination. Therefore by eliminating ACLs within a domain by modifying the ingress/egress points with equivalent functionality an improvement in the overall performance can be obtained. This paper considers the effect of the delays when using router operating systems offering different levels of functionality. It considers factors which contribute to the delay particularly due to ACLs and by using theoretical principles modified by practical calculation a model is created. Additionally this paper provides an example of an optimized solution which reduces the delay through network routers by distributing the security rules to the ingress/egress points of the domain without affecting the security policy.

  7. The Deployment of Routing Protocols in Distributed Control Plane of SDN

    Directory of Open Access Journals (Sweden)

    Zhou Jingjing

    2014-01-01

    Full Text Available Software defined network (SDN provides a programmable network through decoupling the data plane, control plane, and application plane from the original closed system, thus revolutionizing the existing network architecture to improve the performance and scalability. In this paper, we learned about the distributed characteristics of Kandoo architecture and, meanwhile, improved and optimized Kandoo’s two levels of controllers based on ideological inspiration of RCP (routing control platform. Finally, we analyzed the deployment strategies of BGP and OSPF protocol in a distributed control plane of SDN. The simulation results show that our deployment strategies are superior to the traditional routing strategies.

  8. Interaction Control Protocols for Distributed Multi-user Multi-camera Environments

    Directory of Open Access Journals (Sweden)

    Gareth W Daniel

    2003-10-01

    Full Text Available Video-centred communication (e.g., video conferencing, multimedia online learning, traffic monitoring, and surveillance is becoming a customary activity in our lives. The management of interactions in such an environment is a complicated HCI issue. In this paper, we present our study on a collection of interaction control protocols for distributed multiuser multi-camera environments. These protocols facilitate different approaches to managing a user's entitlement for controlling a particular camera. We describe a web-based system that allows multiple users to manipulate multiple cameras in varying remote locations. The system was developed using the Java framework, and all protocols discussed have been incorporated into the system. Experiments were designed and conducted to evaluate the effectiveness of these protocols, and to enable the identification of various human factors in a distributed multi-user and multi-camera environment. This work provides an insight into the complexity associated with the interaction management in video-centred communication. It can also serve as a conceptual and experimental framework for further research in this area.

  9. A survey of ring-building network protocols suitable for command and control group communications

    Science.gov (United States)

    Sobeih, Ahmed; Yurcik, William

    2005-05-01

    Multicasting is the enabling technology for group communication. However, network-layer multicasting (e.g., IP multicast) has not been widely adopted more than 10 years of its invention due to the concerns related to deployment, scalability and network management. Application-layer multicast (ALM) has been proposed as an alternative for IP multicast. In ALM, group communications take place on an overlay network in which each edge corresponds to a direct unicast path between two group members. ALM protocols differ in, among other aspects, the topology of the underlying overlay network (e.g., tree, mesh or ring). Ring-based ALM protocols have the advantages of providing a constant node degree, and enabling the implementation of reliable and totally-ordered message delivery through the use of a ring with a token that contains ordering and flow control information. In addition, a ring overlay network topology is inherently reliable to single node failures. In this paper, we provide a survey and a taxonomy of several ring-building group communication protocols. Investigating the major characteristics of ring-building network protocols is an important step towards understanding which of them are suitable for command and control group communications.

  10. Medium Access Control for Opportunistic Concurrent Transmissions under Shadowing Channels

    Directory of Open Access Journals (Sweden)

    Seung Min Hur

    2009-06-01

    Full Text Available We study the problem of how to alleviate the exposed terminal effect in multihop wireless networks in the presence of log-normal shadowing channels. Assuming node location information, we propose an extension of the IEEE 802.11 MAC protocol that schedules concurrent transmissions in the presence of log-normal shadowing, thus mitigating the exposed terminal problem and improving network throughput and delay performance. We observe considerable improvements in throughput and delay achieved over the IEEE 802.11 MAC under various network topologies and channel conditions in ns-2 simulations, which justify the importance of considering channel randomness in MAC protocol design for multihop wireless networks.

  11. An Internet-based treatment for flying phobia (NO-FEAR Airlines): study protocol for a randomized controlled trial.

    Science.gov (United States)

    Campos, Daniel; Bretón-López, Juana; Botella, Cristina; Mira, Adriana; Castilla, Diana; Baños, Rosa; Tortella-Feliu, Miquel; Quero, Soledad

    2016-08-20

    Flying phobia (FP) is a common and disabling mental disorder. Although in vivo exposure is the treatment of choice, it is linked to a number of limitations in its implementation. Particularly important, is the limited access to the feared stimulus (i.e., plane). Moreover, the economic cost of in vivo exposure should be specially considered as well as the difficulty of applying the exposure technique in an appropriate way; controlling important variables such as the duration of the exposure or the number of sessions. ICTs could help to reduce these limitations. Computer-assisted treatments have remarkable advantages in treating FP. Furthermore, they can be delivered through the Internet, increasing their advantages and reaching more people in need. The Internet has been established as an effective way to treat a wide range of mental disorders. However, as far as we know, no controlled studies exist on FP treatment via the Internet. This study aims to evaluate the efficacy of an Internet-based treatment for FP (NO-FEAR Airlines) versus a waiting list control group. Secondary objectives will be to explore two ways of delivering NO-FEAR Airlines, with or without therapist guidance, and study the patients' acceptance of the program. This paper presents the study protocol. The study is a randomized controlled trial. A minimum of 57 participants will be randomly assigned to three conditions: a) NO-FEAR Airlines totally self-applied, b) NO-FEAR Airlines with therapist guidance, or c) a waiting list control group (6 weeks). Primary outcomes measures will be the Fear of Flying Questionnaire-II and the Fear of Flying Scale. Secondary outcomes will be included to assess other relevant clinical measures, such as the Fear and Avoidance Scales, Clinician Severity Scale, and Patient's Improvement scale. Analyses of post-treatment flights will be conducted. Treatment acceptance and preference measures will also be included. Intention-to-treat and per protocol analyses will be

  12. Performance analysis and overload control of an open service access (OSA) architecture

    Science.gov (United States)

    Andersson, Jens K.; Nyberg, Christian; Kihl, Maria

    2003-08-01

    The trend of the service architectures developed in telecommunications today is that they should be open in the sense that they can communicate over the borders of different networks. Instead of each network having their own service architecture with their own applications, all networks should be able to use the same applications. 3GPP, the organization developing specifications for the 3G networks has specified the standard Open Service Access (OSA), as a part of the 3G specification. OSA offers different Application Protocol Interfaces that enable an application that resides outside a network to use the capabilities of the network. This paper analyses the performance of an OSA gateway. It is examined how the overload control can be dealt with in a way to best satisfy the operators and the 3'rd parties. There are some guiding principles in the specifications, but a lot of decisions have to be made by the implementors of application servers and OSA gateways. Proposals of different requirements for an OSA architecture exist such as, minimum amount of accepted calls per second and time constraint for the maximal total delay for an application. Maximal and fair throughput have to be prioritized from the 3'rd parties view, but profit is the main interest from the operators point of view. Therefore this paper examines a priority based proposal of an overload control mechanism taking these aspects and requirements into account.

  13. Whole Body Vibration Exercise Protocol versus a Standard Exercise Protocol after ACL Reconstruction: A Clinical Randomized Controlled Trial with Short Term Follow-Up

    Directory of Open Access Journals (Sweden)

    Gereon Berschin

    2014-09-01

    Full Text Available The suitability and effectiveness of whole body vibration (WBV exercise in rehabilitation after injury of the anterior cruciate ligament (ACL was studied using a specially designed WBV protocol. We wanted to test the hypothesis if WBV leads to superior short term results regarding neuromuscular performance (strength and coordination and would be less time consuming than a current standard muscle strengthening protocol. In this prospective randomized controlled clinical trial, forty patients who tore their ACL and underwent subsequent ligament reconstruction were enrolled. Patients were randomized to the whole body vibration (n=20 or standard rehabilitation exercise protocol (n=20. Both protocols started in the 2nd week after surgery. Isometric and isokinetic strength measurements, clinical assessment, Lysholm score, neuromuscular performance were conducted weeks 2, 5, 8 and 11 after surgery. Time spent for rehabilitation exercise was reduced to less than a half in the WBV group. There were no statistically significant differences in terms of clinical assessment, Lysholm score, isokinetic and isometric strength. The WBV group displayed significant better results in the stability test. In conclusion, preliminary data indicate that our whole body vibration muscle exercise protocol seems to be a good alternative to a standard exercise program in ACL-rehabilitation. Despite of its significant reduced time requirement it is at least equally effective compared to a standard rehabilitation protocol.

  14. HIERARCHICAL ACCESS CONTROL IN DYNAMIC PEER GROUPS USING SYMMETRIC POLYNOMIAL AND TREE BASED GROUP ELLIPTIC CURVE DIFFIE HELLMAN SCHEME

    Directory of Open Access Journals (Sweden)

    Nafeesa Begum Jeddy

    2014-01-01

    Full Text Available Hierarchical Access Control in group communication is an active area of research which is difficult to achieve it. Its primary objective is to allow users of a higher authority group to access information or resource held by lower group users and preventing the lower group users to access information held by higher class users. Large collection of collaborative applications in organizations inherently has hierarchical structures for functioning, where providing security by efficient group key management is a big challenging issue. While preserving centralized methods for hierarchical access control, it is difficult to achieve efficiency as a single membership change will result in lot of changes which are difficult to maintain. So, using distributed key agreement techniques is more appropriate for this scenario. This study explore on novel group key agreement approach, which combines both the symmetric polynomial scheme and Tree Based Group elliptic Curve key exchange. Also, it yields a secure protocol suite that is good in fault-tolerant and simple. The efficiency of SP-TGECDH is better than many other schemes. Using TGECDH makes the scheme suitable small Low powered devices.

  15. An Efficient Role and Object Based Access Control Model Implemented in a PDM System

    Institute of Scientific and Technical Information of China (English)

    HUANG Xiaowen; TAN Jian; HUANG Xiangguo

    2006-01-01

    An effective and reliable access control is crucial to a PDM system. This article has discussed the commonly used access control models, analyzed their advantages and disadvantages, and proposed a new Role and Object based access control model that suits the particular needs of a PDM system. The new model has been implemented in a commercial PDM system, which has demonstrated enhanced flexibility and convenience.

  16. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    OpenAIRE

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an active mobile device to enforce centralized ACL-based access control policies. Selective RFID Jamming also solves a Differential Signal Analysis attack to which the RFID Blocker Tag is susceptible.

  17. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    OpenAIRE

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an active mobile device to enforce centralized ACL-based access control policies. Selective RFID Jamming also solves a Differential Signal Analysis attack to which the RFID Blocker Tag is susceptible.

  18. 21 CFR 1311.125 - Requirements for establishing logical access control-Individual practitioner.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Requirements for establishing logical access... Prescriptions § 1311.125 Requirements for establishing logical access control—Individual practitioner. (a) At... his two-factor authentication credential to satisfy the logical access controls. The second...

  19. 21 CFR 1311.130 - Requirements for establishing logical access control-Institutional practitioner.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Requirements for establishing logical access...) Electronic Prescriptions § 1311.130 Requirements for establishing logical access control—Institutional... practitioner that enters permissions for logical access controls into the application. The...

  20. 78 FR 16757 - Twentieth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-03-18

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held April 4, 2013 from...

  1. 76 FR 59481 - Ninth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-09-26

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems. SUMMARY: The FAA is issuing this notice to advise the public of a meeting of RTCA Special Committee 224: Airport Security Access Control...

  2. 78 FR 43963 - Twenty-Third Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-07-22

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held on June 20,...

  3. 77 FR 71474 - Seventeenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-11-30

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held December 13,...

  4. 77 FR 15448 - Twelfth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-03-15

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of meeting RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... 224, Airport Security Access Control Systems DATES: The meeting will be held April 5, 2012, from 10...

  5. 78 FR 22025 - Twenty First Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-04-12

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held April 9-10,...

  6. 77 FR 55894 - Fifteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-09-11

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems DATES: The meeting will be held September 27-28,...

  7. 76 FR 38742 - Seventh Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-07-01

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held July 15, 2011, from 10 a.m. to 1 p.m....

  8. 77 FR 64838 - Sixteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-10-23

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held November 15,...

  9. 78 FR 7850 - Nineteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2013-02-04

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Meeting Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY... Committee 224, Airport Security Access Control Systems. DATES: The meeting will be held February 21,...

  10. 76 FR 3931 - Fourth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-01-21

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 Meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held February 8, 2011, from 10 a.m. to 5...

  11. 75 FR 71790 - Second Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-11-24

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 224 meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is... Access Control Systems. DATES: The meeting will be held December 9, 2010, from 10 a.m. to 5...

  12. 77 FR 2343 - Eleventh Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    Science.gov (United States)

    2012-01-17

    ... Control Systems AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION: Notice of RTCA Special Committee 224, Airport Security Access Control Systems. SUMMARY: The FAA..., Airport Security Access Control Systems. DATES: The meeting will be held February 9, 2012, from 10...

  13. Nonadherence to treatment protocol in published randomised controlled trials: a review

    Directory of Open Access Journals (Sweden)

    Dodd Susanna

    2012-06-01

    Full Text Available Abstract This review aimed to ascertain the extent to which nonadherence to treatment protocol is reported and addressed in a cohort of published analyses of randomised controlled trials (RCTs. One hundred publications of RCTs, randomly selected from those published in BMJ, New England Journal of Medicine, the Journal of the American Medical Association and The Lancet during 2008, were reviewed to determine the extent and nature of reported nonadherence to treatment protocol, and whether statistical methods were used to examine the effect of such nonadherence on both benefit and harms analyses. We also assessed the quality of trial reporting of treatment protocol nonadherence and the quality of reporting of the statistical analysis methods used to investigate such nonadherence. Nonadherence to treatment protocol was reported in 98 of the 100 trials, but reporting on such nonadherence was often vague or incomplete. Forty-two publications did not state how many participants started their randomised treatment. Reporting of treatment initiation and completeness was judged to be inadequate in 64% of trials with short-term interventions and 89% of trials with long-term interventions. More than half (51 of the 98 trials with treatment protocol nonadherence implemented some statistical method to address this issue, most commonly based on per protocol analysis (46 but often labelled as intention to treat (ITT or modified ITT (23 analyses in 22 trials. The composition of analysis sets for their benefit outcomes were not explained in 57% of trials, and 62% of trials that presented harms analyses did not define harms analysis populations. The majority of defined harms analysis populations (18 out of 26 trials, 69% were based on actual treatment received, while the majority of trials with undefined harms analysis populations (31 out of 43 trials, 72% appeared to analyse harms using the ITT approach. Adherence to randomised intervention is poorly considered

  14. Wi-Fi Networks Security and Accessing Control

    Directory of Open Access Journals (Sweden)

    Tarek S. Sobh

    2013-06-01

    Full Text Available As wireless networks access gains popularity in corporate, private and personal networks, the nature of wireless networks opens up new possibilities for network attacks. This paper negotiating Wi-Fi security against scanning of rogue Wi-Fi networks and other related activities and considers the monitoring of Wi-Fi traffic effects. The unauthorized access point (AP problem has raised more attention and resulted in obtaining wireless access without subscriber permission.This work assumes Wi-Fi AP under attack specially rogue AP and/or ad-hoc client. It provides a solution for detecting and preventing this attack. In addition, it provides the required user permissions to allow/block access of the files on the user of ad-hoc client. The experiments include the rogue AP attack are maintained and the effectiveness of the proposed solution are tested.

  15. Optical label-controlled transparent metro-access network interface

    DEFF Research Database (Denmark)

    Osadchiy, Alexey Vladimirovich

    This thesis presents results obtained during the course of my PhD research on optical signal routing and interfacing between the metropolitan and access segments of optical networks. Due to both increasing capacity demands and variety of emerging services types, new technological challenges...... are arising for seamlessly interfacing metropolitan and access networks. Therefore, in this PhD project, I have analyzed those technological challenges and identified the key aspects to be addressed. I have also proposed and experimentally verified a number of solutions to metropolitan and access networks...... interfacing and signal routing. Equipment and infrastructure simplification was recognized as the path towards more efficient metropolitan and access networks providing a spectrum of high-bandwidth services to large number of users. Several approaches have been proposed and developed in order to enable...

  16. Software protocol design: Communication and control in a multi-task robot machine for ITER vacuum vessel assembly and maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ming, E-mail: ming.li@lut.fi [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland); Wu, Huapeng; Handroos, Heikki [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland); Yang, Guangyou [School of Mechanical Engineering, Hubei University of Technology, Wuhan (China); Wang, Yongbo [Laboratory of Intelligent Machines, Lappeenranta University of Technology (Finland)

    2015-10-15

    Highlights: • A high-level protocol is proposed for the data inter-transmission. • The protocol design is task-oriented for the robot control in the software system. • The protocol functions as a role of middleware in the software. • The protocol running stand-alone as an independent process in the software provides greater security. • Providing a reference design protocol for the multi-task robot machine in the industry. - Abstract: A specific communication and control protocol for software design of a multi-task robot machine is proposed. In order to fulfill the requirements on the complicated multi machining functions and the high performance motion control, the software design of robot is divided into two main parts accordingly, which consists of the user-oriented HMI part and robot control-oriented real-time control system. The two parts of software are deployed in the different hardware for the consideration of run-time performance, which forms a client–server-control architecture. Therefore a high-level task-oriented protocol is designed for the data inter-communication between the HMI part and the control system part, in which all the transmitting data related to a machining task is divided into three categories: trajectory-oriented data, task control-oriented data and status monitoring-oriented data. The protocol consists of three sub-protocols accordingly – a trajectory protocol, task control protocol and status protocol – which are deployed over the Ethernet and run as independent processes in both the client and server computers. The protocols are able to manage the vast amounts of data streaming due to the multi machining functions in a more efficient way. Since the protocol is functioning in the software as a role of middleware, and providing the data interface standards for the developing groups of two parts of software, it also permits greater focus of both software parts developers on their own requirements-oriented design. By

  17. GMPLS: IP-Centric Control Protocols for Optical Networks(Tutorial)

    Institute of Scientific and Technical Information of China (English)

    Yaohui Jin; Weisheng Hu

    2003-01-01

    Recent advances in optical networking technologies, particularly DWDM and MEMS, promise the transmission and switching of huge bandwidth capacity. The carriers have convinced of that their revenue must be earned from efficient bandwidth management instead of unsophisticated increase in capacity. The distributed control plane can offer more flexibility, reliability and scalability, whose functions include addressing, resource and topology discovery, route computation, provisioning and restoration. Generalized Multi-Protocol Label Switching (GMPLS), an IP-centric control plane, inherit the best features of IP and ATM technologies in terms of QoS and traffic engineering. Besides,GMPLS introduces enhancements to the existing IP routing and signaling protocols by supporting not only packet switching networks (IP) and frame/cell switching networks (ATM), but also networks that perform switching in time (e.g. SDH/SONET, PDH, G.709), wavelength (lambdas), and space (fiber) domain.

  18. How to Improve the Accessibility and Reduce the Total Cost of Ownership with Ecolig Protocol and Android in Mobile Learning

    Directory of Open Access Journals (Sweden)

    Samira Muhammad Ismail

    2011-10-01

    Full Text Available A new electronic learning device generation can be created from a new paradigm in human sense and efferent resources. The brain computer interfaces (BCI with ECOLIG protocol can be used to get the advantages from “Near To Eye” and “Augmented Reality” technologies. In this way, this paper describes the results from an experiment using a mobile phone emulator system, a BCI and ECOLIG protocol to demonstrate the benefits in eliminating the use of touch screen and keyboards features. Finally, it concludes that ECOLIG can be a long life time communication technology between Human and Machines especially in a Singularity world.

  19. How to Improve the Accessibility and Reduce the Total Cost of Ownership with Ecolig Protocol and Android in Mobile Learning

    OpenAIRE

    Samira Muhammad Ismail; Paulo Victor de Oliveira Miguel; Gilmar Barreto

    2011-01-01

    A new electronic learning device generation can be created from a new paradigm in human sense and efferent resources. The brain computer interfaces (BCI) with ECOLIG protocol can be used to get the advantages from “Near To Eye” and “Augmented Reality” technologies. In this way, this paper describes the results from an experiment using a mobile phone emulator system, a BCI and ECOLIG protocol to demonstrate the benefits in eliminating the use of touch screen and keyboards features. Finally, it...

  20. Role-based access control through on-demand classification of electronic health record.

    Science.gov (United States)

    Tiwari, Basant; Kumar, Abhay

    2015-01-01

    Electronic health records (EHR) provides convenient method to exchange medical information of patients between different healthcare providers. Access control mechanism in healthcare services characterises authorising users to access EHR records. Role Based Access Control helps to restrict EHRs to users in a certain role. Significant works have been carried out for access control since last one decade but little emphasis has been given to on-demand role based access control. Presented work achieved access control through physical data isolation which is more robust and secure. We propose an algorithm in which selective combination of policies for each user of the EHR database has been defined. We extend well known data mining technique 'classification' to group EHRs with respect to the given role. Algorithm works by taking various roles as class and defined their features as a vector. Here, features are used as a Feature Vector for classification to describe user authority.

  1. Task-and-role-based access-control model for computational grid

    Institute of Scientific and Technical Information of China (English)

    LONG Tao; HONG Fan; WU Chi; SUN Ling-li

    2007-01-01

    Access control in a grid environment is a challenging issue because the heterogeneous nature and independent administration of geographically dispersed resources in grid require access control to use fine-grained policies. We established a task-and-role-based access-control model for computational grid (CG-TRBAC model), integrating the concepts of role-based access control (RBAC) and task-based access control (TBAC). In this model, condition restrictions are defined and concepts specifically tailored to Workflow Management System are simplified or omitted so that role assignment and security administration fit computational grid better than traditional models; permissions are mutable with the task status and system variables, and can be dynamically controlled. The CG-TRBAC model is proved flexible and extendible. It can implement different control policies. It embodies the security principle of least privilege and executes active dynamic authorization. A task attribute can be extended to satisfy different requirements in a real grid system.

  2. Plasticity-Inducing TMS Protocols to Investigate Somatosensory Control of Hand Function

    Directory of Open Access Journals (Sweden)

    M. Jacobs

    2012-01-01

    Full Text Available Hand function depends on sensory feedback to direct an appropriate motor response. There is clear evidence that somatosensory cortices modulate motor behaviour and physiology within primary motor cortex. However, this information is mainly from research in animals and the bridge to human hand control is needed. Emerging evidence in humans supports the notion that somatosensory cortices modulate motor behaviour, physiology and sensory perception. Transcranial magnetic stimulation (TMS allows for the investigation of primary and higher-order somatosensory cortices and their role in control of hand movement in humans. This review provides a summary of several TMS protocols in the investigation of hand control via the somatosensory cortices. TMS plasticity inducing protocols reviewed include paired associative stimulation, repetitive TMS, theta-burst stimulation as well as other techniques that aim to modulate cortical excitability in sensorimotor cortices. Although the discussed techniques may modulate cortical excitability, careful consideration of experimental design is needed to isolate factors that may interfere with desired results of the plasticity-inducing protocol, specifically events that may lead to metaplasticity within the targeted cortex.

  3. Medium Access Control for Opportunistic Concurrent Transmissions under Shadowing Channels.

    Science.gov (United States)

    Son, In Keun; Mao, Shiwen; Hur, Seung Min

    2009-01-01

    We study the problem of how to alleviate the exposed terminal effect in multi-hop wireless networks in the presence of log-normal shadowing channels. Assuming node location information, we propose an extension of the IEEE 802.11 MAC protocol that sched-ules concurrent transmissions in the presence of log-normal shadowing, thus mitigating the exposed terminal problem and improving network throughput and delay performance. We observe considerable improvements in throughput and delay achieved over the IEEE 802.11 MAC under various network topologies and channel conditions in ns-2 simulations, which justify the importance of considering channel randomness in MAC protocol design for multi-hop wireless networks.

  4. The Model and Control Methods of Access to Information and Technology Resources of Automated Control Systems in Water Supply Industry

    Science.gov (United States)

    Rytov, M. Yu; Spichyack, S. A.; Fedorov, V. P.; Petreshin, D. I.

    2017-01-01

    The paper describes a formalized control model of access to information and technological resources of automated control systems at water supply enterprises. The given model considers the availability of various communication links with information systems and technological equipment. There are also studied control methods of access to information and technological resources of automated control systems at water supply enterprises. On the basis of the formalized control model and appropriate methods there was developed a software-hardware complex for rapid access to information and technological resources of automated control systems, which contains an administrator’s automated workplace and ultimate users.

  5. Study Application of RADIUS Protocol on Ethernet

    Institute of Scientific and Technical Information of China (English)

    GUO Fang; YANG Huan-yu; LI Hong

    2004-01-01

    This paper presents how to apply the RADIUS (Remote Authentication Dial In User Service)protocol ,which is generally applied to dial-up network, to the authentication & charge of Broad Band accessing control system on Ethernet. It is provided that the Broad Band accessing control system included a self-designed communication protocol is used in communicating between an terminal user and Network Access Server .The interface module on the servers side and the Radius system is also given in this article.

  6. Implementing Discretionary Access Control with Time Character in Linux and Performance Analysis

    Institute of Scientific and Technical Information of China (English)

    TAN Liang; ZHOU Ming-Tian

    2006-01-01

    DAC (Discretionary Access Control Policy) is access control based on ownership relations between subject and object, the subject can discretionarily decide on that who, by what methods, can access his owns object. In this paper, the system time is looked as a basic secure element. The DAC_T (Discretionary Access Control Policy with Time Character) is presented and formalized. The DAC_T resolves that the subject can discretionarily decide that who, on when, can access his owns objects. And then the DAC_T is implemented on Linux based on GFAC (General Framework for Access Control), and the algorithm is put forward. Finally, the performance analysis for the DAC_T_Linux is carried out. It is proved that the DAC_T_Linux not only can realize time constraints between subject and object but also can still be accepted by us though its performance have been decreased.

  7. Synthesizing Existing CSMA and TDMA Based MAC Protocols for VANETs.

    Science.gov (United States)

    Huang, Jiawei; Li, Qi; Zhong, Shaohua; Liu, Lianhai; Zhong, Ping; Wang, Jianxin; Ye, Jin

    2017-02-10

    Many Carrier Sense Multiple Access (CSMA) and Time Division Multiple Access (TDMA) based medium access control (MAC) protocols for vehicular ad hoc networks (VANETs) have been proposed recently. Contrary to the common perception that they are competitors, we argue that the underlying strategies used in these MAC protocols are complementary. Based on this insight, we design CTMAC, a MAC protocol that synthesizes existing strategies; namely, random accessing channel (used in CSMA-style protocols) and arbitral reserving channel (used in TDMA-based protocols). CTMAC swiftly changes its strategy according to the vehicle density, and its performance is better than the state-of-the-art protocols. We evaluate CTMAC using at-scale simulations. Our results show that CTMAC reduces the channel completion time and increases the network goodput by 45% for a wide range of application workloads and network settings.

  8. A Generic Role Based Access Control Model for Wind Power Systems

    DEFF Research Database (Denmark)

    Nagarajan, Anand; Jensen, Christian D.

    2010-01-01

    infrastructure in a software domain in a manufacturer independent manner as well as establishing secure communication and authenticating the other parties in electrical power infrastructures, but they do not address the problem of access control. We therefore propose a generic model for access control in wind...... power systems, which is based on the widely used role-based access control model. The proposed model is tested using a prototype designed in conformance with the standards that are in use in modern wind power infrastructure and the results are presented to determine the overhead in communication caused...... while adhering to the proposed access model....

  9. An effective access control approach to support mobility in IPv6 networks

    Science.gov (United States)

    Peng, Xue-hai; Lin, Chuang

    2005-11-01

    Access control is an important method to improve network security and prevent protected resources from being used by some nodes without authority. Moreover, mobility is an important trend of internet. In this paper, based on the architecture of hierarchical mobile IPv6, we proposed an effective access control approach to support mobility in IPv6 networks, which can ensure the operation of access control when a mobile node roams in these domains with different polices, with decreased delay of access negotiation and cost of delivering messages.

  10. Identity driven Capability based Access Control (ICAC) Scheme for the Internet of Things

    DEFF Research Database (Denmark)

    Mahalle, Parikshit N.; Anggorojati, Bayu; Prasad, Neeli R.

    2012-01-01

    Internet of Things (IoT) becomes discretionary part of everyday life. Scalability and manageability is daunting due to unbounded number of devices and services. Access control and authorization in IoT with least privilege is equally important to establish secure communication between multiple...... devices and services. In this paper, the concept of capability for access control is introduced where the identities of the involved devices are entrenched in the access capabilities. Identity driven capability based access control (ICAC) scheme presented in this paper helps to alleviate issues related...

  11. Efficacy and Safety of Electroacupuncture on Treating Depression Related Sleep Disorders: Study Protocol of a Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Xuan Yin

    2016-01-01

    Full Text Available Background. Depression is frequently accompanied by sleep disturbances including insomnia. Insomnia may persist even after mood symptoms have been adequately treated. Acupuncture is considered to be beneficial to adjust the state of body and mind and restore the normal sleep-awake cycle. This trial is aimed at evaluating the efficacy and safety of electroacupuncture on treating insomnia in patients with depression. Methods. We describe a protocol for a randomized, single-blinded, sham controlled trial. Ninety eligible patients will be randomly assigned to one of 3 treatment groups: treatment group (acupuncture, control A group (superficial acupuncture at sham points, and control B group (sham acupuncture. All treatment will be given 3 times per week for 8 weeks. The primary outcome is the Pittsburgh Sleep Quality Index (PSQI. The secondary outcomes are sleep parameters recorded in the Actigraphy, Hamilton Rating Scale for Depression (HAMD, and Self-Rating Depression Scale (SDS. All adverse effects will be accessed by the Treatment Emergent Symptom Scale (TESS. Outcomes will be evaluated at baseline, 4 weeks after treatment, 8 weeks after treatment, and 4 weeks of follow-up. Ethics. This trial has been approved by the Ethics Committee of Shanghai Municipal Hospital of Traditional Chinese Medicine (2015SHL-KY-21 and is registered with ChiCTR-IIR-16008058.

  12. Authenticated Blind Issuing of Symmetric Keys for Mobile Access Control System without Trusted Parties

    Directory of Open Access Journals (Sweden)

    Shin-Yan Chiou

    2013-01-01

    Full Text Available Mobile authentication can be used to verify a mobile user’s identity. Normally this is accomplished through the use of logon passwords, but this can raise the secret-key agreement problem between entities. This issue can be resolved by using a public-key cryptosystem, but mobile devices have limited computation ability and battery capacity and a PKI is needed. In this paper, we propose an efficient, non-PKI, authenticated, and blind issued symmetric key protocol for mobile access control systems. An easy-to-deploy authentication and authenticated key agreement system is designed such that empowered mobile devices can directly authorize other mobile devices to exchange keys with the server upon authentication using a non-PKI system without trusted parties. Empowered mobile users do not know the key value of the other mobile devices, preventing users from impersonating other individuals. Also, for security considerations, this system can revoke specific keys or keys issued by a specific user. The scheme is secure, efficient, and feasible and can be implemented in existing environments.

  13. Priority Based Congestion Control Dynamic Clustering Protocol in Mobile Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    R. Beulah Jayakumari

    2015-01-01

    Full Text Available Wireless sensor network is widely used to monitor natural phenomena because natural disaster has globally increased which causes significant loss of life, economic setback, and social development. Saving energy in a wireless sensor network (WSN is a critical factor to be considered. The sensor nodes are deployed to sense, compute, and communicate alerts in a WSN which are used to prevent natural hazards. Generally communication consumes more energy than sensing and computing; hence cluster based protocol is preferred. Even with clustering, multiclass traffic creates congested hotspots in the cluster, thereby causing packet loss and delay. In order to conserve energy and to avoid congestion during multiclass traffic a novel Priority Based Congestion Control Dynamic Clustering (PCCDC protocol is developed. PCCDC is designed with mobile nodes which are organized dynamically into clusters to provide complete coverage and connectivity. PCCDC computes congestion at intra- and intercluster level using linear and binary feedback method. Each mobile node within the cluster has an appropriate queue model for scheduling prioritized packet during congestion without drop or delay. Simulation results have proven that packet drop, control overhead, and end-to-end delay are much lower in PCCDC which in turn significantly increases packet delivery ratio, network lifetime, and residual energy when compared with PASCC protocol.

  14. Priority Based Congestion Control Dynamic Clustering Protocol in Mobile Wireless Sensor Networks.

    Science.gov (United States)

    Jayakumari, R Beulah; Senthilkumar, V Jawahar

    2015-01-01

    Wireless sensor network is widely used to monitor natural phenomena because natural disaster has globally increased which causes significant loss of life, economic setback, and social development. Saving energy in a wireless sensor network (WSN) is a critical factor to be considered. The sensor nodes are deployed to sense, compute, and communicate alerts in a WSN which are used to prevent natural hazards. Generally communication consumes more energy than sensing and computing; hence cluster based protocol is preferred. Even with clustering, multiclass traffic creates congested hotspots in the cluster, thereby causing packet loss and delay. In order to conserve energy and to avoid congestion during multiclass traffic a novel Priority Based Congestion Control Dynamic Clustering (PCCDC) protocol is developed. PCCDC is designed with mobile nodes which are organized dynamically into clusters to provide complete coverage and connectivity. PCCDC computes congestion at intra- and intercluster level using linear and binary feedback method. Each mobile node within the cluster has an appropriate queue model for scheduling prioritized packet during congestion without drop or delay. Simulation results have proven that packet drop, control overhead, and end-to-end delay are much lower in PCCDC which in turn significantly increases packet delivery ratio, network lifetime, and residual energy when compared with PASCC protocol.

  15. Open access, readership, citations: a randomized controlled trial of scientific journal publishing.

    Science.gov (United States)

    Davis, Philip M

    2011-07-01

    Does free access to journal articles result in greater diffusion of scientific knowledge? Using a randomized controlled trial of open access publishing, involving 36 participating journals in the sciences, social sciences, and humanities, we report on the effects of free access on article downloads and citations. Articles placed in the open access condition (n=712) received significantly more downloads and reached a broader audience within the first year, yet were cited no more frequently, nor earlier, than subscription-access control articles (n=2533) within 3 yr. These results may be explained by social stratification, a process that concentrates scientific authors at a small number of elite research universities with excellent access to the scientific literature. The real beneficiaries of open access publishing may not be the research community but communities of practice that consume, but rarely contribute to, the corpus of literature.

  16. Throughput Analysis of Power Control B-MAC Protocol In WSN

    Directory of Open Access Journals (Sweden)

    Ramchand V

    2012-07-01

    Full Text Available This paper presents a new methodology for energy consumption of nodes and throughput analysis has been performed through simulation for B-MAC protocol in Wireless Sensor Networks. The design includes transmission power control and multi-hop transmission of frames through adjusted transmitted power level. Proposed model reduces collision with contention level notification. The proposed model has been simulated using MATLAB. The simulations reveal better results for throughput of the proposed model as compared to B-MAC protocol. In this model we have included a mechanism for node discovery to find the location of the node before transmission of data to it. This increases the throughput of the network since the position of a dislocated node has been found, that results into successful transmission of frames.However, the energy consumption of a node increases due to energy consumed in node discovery.

  17. H-RBAC: A Hierarchical Access Control Model for SaaS Systems

    Directory of Open Access Journals (Sweden)

    Dancheng Li

    2011-08-01

    Full Text Available SaaS is a new way to deploy software as a hosted service and accessed over the Internet which means the customers don’t need to maintain the software code and data on their own servers. So it’s more important for SaaS systems to take security issues into account. Access control is a security mechanism that enables an authority to access to certain restricted areas and resources according to the permissions assigned to a user. Several access models have been proposed to realize the access control of single instance systems. However, most of the existing models couldn’t address the following SaaS system problems: (1 role name conflicts (2 cross-level management (3 the isomerism of tenants' access control (4 temporal delegation constraints. This paper describes a hierarchical RBAC model called H-RBAC solves all the four problems of SaaS systems mentioned above. This model addresses the SaaS system access control in both system level and tenant level. It combines the advantages of RBDM and ARBAC97 model and introduces temporal constraints to SaaS access control model. In addition, a practical approach to implement the access control module for SaaS systems based on H-RBAC model is also proposed in this paper.

  18. Access control and privilege management in electronic health record: a systematic literature review.

    Science.gov (United States)

    Jayabalan, Manoj; O'Daniel, Thomas

    2016-12-01

    This study presents a systematic literature review of access control for electronic health record systems to protect patient's privacy. Articles from 2006 to 2016 were extracted from the ACM Digital Library, IEEE Xplore Digital Library, Science Direct, MEDLINE, and MetaPress using broad eligibility criteria, and chosen for inclusion based on analysis of ISO22600. Cryptographic standards and methods were left outside the scope of this review. Three broad classes of models are being actively investigated and developed: access control for electronic health records, access control for interoperability, and access control for risk analysis. Traditional role-based access control models are extended with spatial, temporal, probabilistic, dynamic, and semantic aspects to capture contextual information and provide granular access control. Maintenance of audit trails and facilities for overriding normal roles to allow full access in emergency cases are common features. Access privilege frameworks utilizing ontology-based knowledge representation for defining the rules have attracted considerable interest, due to the higher level of abstraction that makes it possible to model domain knowledge and validate access requests efficiently.

  19. A Unified Access Model for Interconnecting Heterogeneous Wireless Networks

    Science.gov (United States)

    2015-05-01

    with each other via a central controller. The 2 access technologies used were 802.11 ( WiFi ) and a Carrier-Sense Multiple Access (CSMA) protocol ...wireless subnets could communicate with each other. 3. Results and Discussion Using the 3-VM LTE/ WiFi configuration, we placed a User Datagram Protocol ...control plane protocols . A network model that can abstract disparate MAC layers in heterogeneous networks and interconnect them using a unified and

  20. 75 FR 47464 - Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control...

    Science.gov (United States)

    2010-08-06

    ... circumvention of copyright protection systems for access control technologies which was published July 27, 2010... Copyright Office 37 CFR Part 201 Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control Technologies AGENCY: Copyright Office, Library of Congress. ACTION: Final...

  1. 75 FR 61819 - First Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-10-06

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): November 2, 2010 Welcome/Introductions/Administrative Remarks Agenda... Federal Aviation Administration First Meeting: RTCA Special Committee 224: Airport Security Access...

  2. 76 FR 16470 - Sixth Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2011-03-23

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): Agenda April 13, 2011 Welcome/Introductions/Administrative Remarks... Federal Aviation Administration Sixth Meeting: RTCA Special Committee 224: Airport Security Access...

  3. 75 FR 80886 - Third Meeting: RTCA Special Committee 224: Airport Security Access Control Systems

    Science.gov (United States)

    2010-12-23

    ... meeting: Airport Security Access Control Systems (Update to DO-230B). SUMMARY: The FAA is issuing this... Control Systems (Update to DO-230B): Agenda January 13, 2011 Welcome/Introductions/Administrative Remarks... Federal Aviation Administration Third Meeting: RTCA Special Committee 224: Airport Security Access...

  4. Owner-Based Role-Based Access Control OB-RBAC

    NARCIS (Netherlands)

    Saffarian, Mohsen; Sadighi, Babak

    2010-01-01

    Administration of an access control model deals with the question of who is authorized to update policies defined on the basis of that model. One of the models whose administration has absorbed relatively large research is the Role-Based Access Control (RBAC) model. All the existing role-based admin

  5. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    NARCIS (Netherlands)

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an a

  6. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    NARCIS (Netherlands)

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an a

  7. A novel decentralized hierarchical access control scheme for the medical scenario

    DEFF Research Database (Denmark)

    Eskeland, Sigurd; Prasad, Neeli R.

    2006-01-01

    to be the property of the corresponding patient, it is justified that patients should have the opportunity to exert control over their own data. In this paper, we propose a cryptographic access control scheme allowing patients to grant medical teams authorizations to access their medical data. Moreover...

  8. Enhancing Security and Privacy in Video Surveillance through Role-Oriented Access Control Mechanism

    DEFF Research Database (Denmark)

    Mahmood Rajpoot, Qasim

    the explicitly stated ones due to the hierarchical relations between the attributes of different entities. We implement a prototype of the proposed mechanism and demonstrate that the access control policies using our approach may be specified via eXtensible Access Control Markup Language (XACML)....

  9. Modelling and Analysing Access Control Policies in XACML 3.0

    DEFF Research Database (Denmark)

    Ramli, Carroline Dewi Puspa Kencana

    XACML (eXtensible Access Control Markup Language) is a prominent access control language that is widely adopted both in industry and academia. XACML is an international standard in the field of information security. The problem with XACML is that its specification is described in natural language...

  10. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    NARCIS (Netherlands)

    Rieback, Melanie; Crispo, Bruno; Tanenbaum, Andrew

    2007-01-01

    This paper introduces an off-tag RFID access control mechanism called “Selective RFID Jamming”. Selective RFID Jamming protects low-cost RFID tags by enforcing access control on their behalf, in a similar manner to the RFID Blocker Tag. However, Selective RFID Jamming is novel because it uses an

  11. A dynamic access control method based on QoS requirement

    Science.gov (United States)

    Li, Chunquan; Wang, Yanwei; Yang, Baoye; Hu, Chunyang

    2013-03-01

    A dynamic access control method is put forward to ensure the security of the sharing service in Cloud Manufacturing, according to the application characteristics of cloud manufacturing collaborative task. The role-based access control (RBAC) model is extended according to the characteristics of cloud manufacturing in this method. The constraints are considered, which are from QoS requirement of the task context to access control, based on the traditional static authorization. The fuzzy policy rules are established about the weighted interval value of permissions. The access control authorities of executable service by users are dynamically adjusted through the fuzzy reasoning based on the QoS requirement of task. The main elements of the model are described. The fuzzy reasoning algorithm of weighted interval value based QoS requirement is studied. An effective method is provided to resolve the access control of cloud manufacturing.

  12. The Study of Access Control for Service-Oriented Computing in Internet of Things

    Directory of Open Access Journals (Sweden)

    Guoping Zhang

    2012-06-01

    Full Text Available In Internet of Things, computing and processing of information is the core supporting. In this paper, we introduce “Service-Oriented Computing” to solve the computing and processing of information in IoT. However, a key challenge in service-oriented environment is the design of effective access control schemas.We put forward a model of Workflow -oriented Attributed Based Access Control (WABAC, and an access control framework based on WABAC model. WABAC model grants and adapts permissions to subjects according to subject atttribute, resource attribute, environment attribute and current task, meeting access control request of SOC. Using the approach presented can effectively enhance the access control security for SOC applications, and prevent the abuse of subject permissions.

  13. Interoperative fundus image and report sharing in compliance with integrating the healthcare enterprise conformance and web access todigital imaging and communication in medicinepersistent object protocol

    Directory of Open Access Journals (Sweden)

    Hui-Qun Wu

    2013-12-01

    Full Text Available AIM:To address issues in interoperability between different fundus image systems, we proposed a web eye-picture archiving and communication system (PACS framework in conformance with digital imaging and communication in medicine (DICOM and health level 7 (HL7 protocol to realize fundus images and reports sharing and communication through internet.METHODS: Firstly, a telemedicine-based eye care work flow was established based on integrating the healthcare enterprise (IHE Eye Care technical framework. Then, a browser/server architecture eye-PACS system was established in conformance with the web access to DICOM persistent object (WADO protocol, which contains three tiers.RESULTS:In any client system installed with web browser, clinicians could log in the eye-PACS to observe fundus images and reports. Multipurpose internet mail extensions (MIME type of a structured report is saved as pdf/html with reference link to relevant fundus image using the WADO syntax could provide enough information for clinicians. Some functions provided by open-source Oviyam could be used to query, zoom, move, measure, view DICOM fundus images.CONCLUSION:Such web eye-PACS in compliance to WADO protocol could be used to store and communicate fundus images and reports, therefore is of great significance for teleophthalmology.

  14. Capability-based Access Control Delegation Model on the Federated IoT Network

    DEFF Research Database (Denmark)

    Anggorojati, Bayu; Mahalle, Parikshit N.; Prasad, Neeli R.

    2012-01-01

    Flexibility is an important property for general access control system and especially in the Internet of Things (IoT), which can be achieved by access or authority delegation. Delegation mechanisms in access control that have been studied until now have been intended mainly for a system that has...... no resource constraint, such as a web-based system, which is not very suitable for a highly pervasive system such as IoT. To this end, this paper presents an access delegation method with security considerations based on Capability-based Context Aware Access Control (CCAAC) model intended for federated...... machine-to-machine communication or IoT networks. The main idea of our proposed model is that the access delegation is realized by means of a capability propagation mechanism, and incorporating the context information as well as secure capability propagation under federated IoT environments. By using...

  15. Blind Cognitive MAC Protocols

    CERN Document Server

    Mehanna, Omar; Gamal, Hesham El

    2008-01-01

    We consider the design of cognitive Medium Access Control (MAC) protocols enabling an unlicensed (secondary) transmitter-receiver pair to communicate over the idle periods of a set of licensed channels, i.e., the primary network. The objective is to maximize data throughput while maintaining the synchronization between secondary users and avoiding interference with licensed (primary) users. No statistical information about the primary traffic is assumed to be available a-priori to the secondary user. We investigate two distinct sensing scenarios. In the first, the secondary transmitter is capable of sensing all the primary channels, whereas it senses one channel only in the second scenario. In both cases, we propose MAC protocols that efficiently learn the statistics of the primary traffic online. Our simulation results demonstrate that the proposed blind protocols asymptotically achieve the throughput obtained when prior knowledge of primary traffic statistics is available.

  16. EVCP: a convergence time improved high-speed transport congestion control protocol

    Institute of Scientific and Technical Information of China (English)

    LU Guang; WANG Yong-chao; ZHU Miao-liang

    2007-01-01

    The Internet evolves to incorporate very-high-bandwidth optical links and more large-delay satellite links. TCP faces new challenges in this unique environment. Theory and experiments showed that TCP becomes inefficient and is prone to be unstable as the per-flow product of bandwidth and latency increases, regardless of the queuing scheme. Variable-structure congestion Control Protocol (VCP) is proposed to address these problems. However, VCP has problem in terms of convergence time,i.e., it takes a long time for a new VCP flow to achieve fair bandwidth allocation if the existing VCP flows have large congestion windows. This paper proposed an Extended Variable-structure congestion Control Protocol (EVCP), which adopted a convergence controller. The basic idea of convergence controller is that if a flow has larger window than its fair window, its congestion window should be decreased more aggressively than usual in Multiplicative Decrease (MD) phase. Simulations showed that EVCP has better performance in terms of convergence time while keeping the advantages of VCP.

  17. Controls Over the Contractor Common Access Card Life Cycle

    Science.gov (United States)

    2008-10-10

    Identification System SES Senior Executive Service SPOC Service Point of Contact TASM Trusted Agent Security Manager USD (AT&L) Under...the final report by October 31, 2008. 53 Finding D. Oversight of Common Access Card Sponsors DoD CVS Service Points of Contact ( SPOCs ...authorization to approve contractor CACs. Organization of CAC Application Sites Each Service agency has an SPOC who is responsible for coordinating with

  18. Evolutionary Games for Multiple Access Control: From Egoism to Altruism

    OpenAIRE

    Gaiech, Houssem; El-Azouzi, Rachid; Haddad, Majed; Altman, Eitan; Mabrouki, Issam

    2014-01-01

    International audience; This paper studies multiple access games within a large population of mobiles decomposed into several groups. Mobiles interfere with each other through many local interactions. We assume that each mobile (or player) cooperates with its group by taking into account the performance of its group. We parameterize the degree of cooperation which allows to cover the fully non-cooperative behavior, the fully cooperative behavior, and even more, the fully altruistic behavior, ...

  19. Supportive Mental Health Self-Monitoring among Smartphone Users with Psychological Distress: Protocol for a Fully Mobile Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Till Beiwinkel

    2017-09-01

    Full Text Available Mobile health (mHealth could be widely used in the population to improve access to psychological treatment. In this paper, we describe the development of a mHealth intervention on the basis of supportive self-monitoring and describe the protocol for a randomized controlled trial to evaluate its effectiveness among smartphone users with psychological distress. Based on power analysis, a representative quota sample of N = 186 smartphone users will be recruited, with an over-sampling of persons with moderate to high distress. Over a 4-week period, the intervention will be compared to a self-monitoring without intervention group and a passive control group. Telephone interviews will be conducted at baseline, post-intervention (4 weeks, and 12-week follow-up to assess study outcomes. The primary outcome will be improvement of mental health. Secondary outcomes will include well-being, intentions toward help-seeking and help-seeking behavior, user activation, attitudes toward mental-health services, perceived stigmatization, smartphone app quality, user satisfaction, engagement, and adherence with the intervention. Additionally, data from the user’s daily life as collected during self-monitoring will be used to investigate risk and protective factors of mental health in real-world settings. Therefore, this study will allow us to demonstrate the effectiveness of a smartphone application as a widely accessible and low-cost intervention to improve mental health on a population level. It also allows to identify new assessment approaches in the field of psychiatric epidemiology.

  20. Characterization of accessibility for affine connection control systems at some points with nonzero velocity

    CERN Document Server

    Barbero-Liñán, María

    2011-01-01

    Affine connection control systems are mechanical control systems that model a wide range of real systems such as robotic legs, hovercrafts, planar rigid bodies, rolling pennies, snakeboards and so on. In 1997 the accessibility and a particular notion of controllability was intrinsically described by A. D. Lewis and R. Murray at points of zero velocity. Here, we present a novel generalization of the description of accessibility algebra for those systems at some points with nonzero velocity as long as the affine connection restricts to the distribution given by the symmetric closure. The results are used to describe the accessibility algebra of different mechanical control systems.

  1. Requirements and Challenges of Location-Based Access Control in Healthcare Emergency Response

    DEFF Research Database (Denmark)

    Vicente, Carmen Ruiz; Kirkpatrick, Michael; Ghinita, Gabriel

    2009-01-01

    Recent advances in positioning and tracking technologies have led to the emergence of novel location-based applications that allow participants to access information relevant to their spatio-temporal context. Traditional access control models, such as role-based access control (RBAC), are not suf......Recent advances in positioning and tracking technologies have led to the emergence of novel location-based applications that allow participants to access information relevant to their spatio-temporal context. Traditional access control models, such as role-based access control (RBAC......), are not sufficient to address the new challenges introduced by these location-based applications. Several recent research efforts have enhanced RBAC with spatio-temporal features. Nevertheless, the state-of-the-art does not deal with mobility of both subjects and objects and does not support the utilization...... of complex access control decisions based on spatio-temporal relationships among subjects and objects. Furthermore, such relationships change frequently in dynamic environments, requiring efficient mechanisms to monitor and re-evaluate access control decisions. In this position paper, we present a healthcare...

  2. Developing a dynamic virtual stimulation protocol to induce linear egomotion during orthostatic posture control test

    Directory of Open Access Journals (Sweden)

    Paulo José Guimarães Da-Silva

    Full Text Available Abstract Introduction In this work, the effect of a dynamic visual stimulation (DS protocol was used to induce egomotion, the center of pressure (COP displacement response. Methods DS was developed concerning the scenario structure (chessboard-pattern floor and furniture and luminance. To move the scenario in a discrete forward (or backward direction, the furniture is expanded (or reduced and the black and white background is reversed during floor translation while the luminance is increased (or reduced by steps of 2 cd/m2. This protocol was evaluated using COP signals from 29 healthy volunteers: standing on a force platform observing the virtual scene (1.72 × 1.16 m projected 1 m ahead (visual incidence angle: θl = 81.4° and θv = 60.2°, which moves with constant velocity (2 m/s during 250 ms. A set of 100 DS was applied in random order, interspersed by a 10 s of static scene. Results The Tukey post-hoc test (p < 0.001 indicated egomotion in the same direction of DS. COP displacement increased over stimulation (8.4 ± 1.7 to 22.6 ±5.3 mm, as well as time to recover stability (4.1 ± 0.4 to 7.2 ± 0.6 s. The peak of egomotion during DSF occurred 200 ms after DSB (Wilcoxon, p = 0.002. Conclusion The dynamic configuration of this protocol establishes virtual flow effects of linear egomotion dependent on the direction of the dynamic visual stimulation. This finding indicates the potential application of the proposed virtual dynamic stimulation protocol to investigate the cortical visual evoked response in postural control studies.

  3. A General Attribute and Rule Based Role-Based Access Control Model

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Growing numbers of users and many access control policies which involve many different resource attributes in service-oriented environments bring various problems in protecting resource. This paper analyzes the relationships of resource attributes to user attributes in all policies, and propose a general attribute and rule based role-based access control(GAR-RBAC) model to meet the security needs. The model can dynamically assign users to roles via rules to meet the need of growing numbers of users. These rules use different attribute expression and permission as a part of authorization constraints, and are defined by analyzing relations of resource attributes to user attributes in many access policies that are defined by the enterprise. The model is a general access control model, and can support many access control policies, and also can be used to wider application for service. The paper also describes how to use the GAR-RBAC model in Web service environments.

  4. A Fault-Tolerant Emergency-Aware Access Control Scheme for Cyber-Physical Systems

    CERN Document Server

    Wu, Guowei; Xia, Feng; Yao, Lin

    2012-01-01

    Access control is an issue of paramount importance in cyber-physical systems (CPS). In this paper, an access control scheme, namely FEAC, is presented for CPS. FEAC can not only provide the ability to control access to data in normal situations, but also adaptively assign emergency-role and permissions to specific subjects and inform subjects without explicit access requests to handle emergency situations in a proactive manner. In FEAC, emergency-group and emergency-dependency are introduced. Emergencies are processed in sequence within the group and in parallel among groups. A priority and dependency model called PD-AGM is used to select optimal response-action execution path aiming to eliminate all emergencies that occurred within the system. Fault-tolerant access control polices are used to address failure in emergency management. A case study of the hospital medical care application shows the effectiveness of FEAC.

  5. Sensors on speaking terms: Schedule-based medium access control protocols for wireless sensor networks

    NARCIS (Netherlands)

    van Hoesel, L.F.W.

    2007-01-01

    Wireless sensor networks make the previously unobservable, observable. The basic idea behind these networks is straightforward: all wires are cut in traditional sensing systems and the sensors are equipped with batteries and radio's to virtually restore the cut wires. The resulting sensors can be pl

  6. Security Mechanisms and Access Control Infrastructure for Biometrics Passport using Cryptographic Protocols

    Directory of Open Access Journals (Sweden)

    V.K. Narendira Kumar

    2013-09-01

    Full Text Available Electronic passports (e-passports are to prevent the illegal entry of traveller into a specific country and limit the use of counterfeit documents by more accurate identification of an individual. The e-passport, as it is sometimes called, represents a bold initiative in the deployment of two new technologies: cryptography security and biometrics (face, fingerprints, palm prints and iris. A passport contains the important personal information of holder such as photo, name, date of birth and place, nationality, date of issue, date of expiry, authority and so on. The goal of the adoption of the electronic passport is not only to expedite processing at border crossings, but also to increase security. The paper explores the privacy and security implications of this impending worldwide experiment in biometrics authentication technology.

  7. Sensors on speaking terms : schedule-based medium access control protocols for wireless sensor networks

    NARCIS (Netherlands)

    Hoesel, van Lodewijk Frans Willem

    2007-01-01

    Wireless sensor networks make the previously unobservable, observable. The basic idea behind these networks is straightforward: all wires are cut in traditional sensing systems and the sensors are equipped with batteries and radio’s to virtually restore the cut wires. The resulting sensors can be pl

  8. Proximity-based access control for context-sensitive information provision in SOA-based systems

    Science.gov (United States)

    Rajappan, Gowri; Wang, Xiaofei; Grant, Robert; Paulini, Matthew

    2014-06-01

    Service Oriented Architecture (SOA) has enabled open-architecture integration of applications within an enterprise. For net-centric Command and Control (C2), this elucidates information sharing between applications and users, a critical requirement for mission success. The Information Technology (IT) access control schemes, which arbitrate who gets access to what information, do not yet have the contextual knowledge to dynamically allow this information sharing to happen dynamically. The access control might prevent legitimate users from accessing information relevant to the current mission context, since this context may be very different from the context for which the access privileges were configured. We evaluate a pair of data relevance measures - proximity and risk - and use these as the basis of dynamic access control. Proximity is a measure of the strength of connection between the user and the resource. However, proximity is not sufficient, since some data might have a negative impact, if leaked, which far outweighs importance to the subject's mission. For this, we use a risk measure to quantify the downside of data compromise. Given these contextual measures of proximity and risk, we investigate extending Attribute-Based Access Control (ABAC), which is used by the Department of Defense, and Role-Based Access Control (RBAC), which is widely used in the civilian market, so that these standards-based access control models are given contextual knowledge to enable dynamic information sharing. Furthermore, we consider the use of such a contextual access control scheme in a SOA-based environment, in particular for net-centric C2.

  9. Design of Active Queue Management for Robust Control on Access Router for Heterogeneous Networks

    Directory of Open Access Journals (Sweden)

    Åhlund Christer

    2011-01-01

    Full Text Available The Internet architecture is a packet switching technology that allows dynamic sharing of bandwidth among different flows with in an IP network. Packets are stored and forwarded from one node to the next until reaching their destination. Major issues in this integration are congestion control and how to meet different quality of service requirements associated with various services. In other words streaming media quality degrades with increased packet delay and jitter caused by network congestion. To mitigate the impact of network congestion, various techniques have been used to improve multimedia quality and one of those techniques is Active Queue Management (AQM. Access routers require a buffer to hold packets during times of congestion. A large buffer can absorb the bursty arrivals, and this tends to increase the link utilizations but results in higher queuing delays. Traffic burstiness has a considerable negative impact on network performance. AQM is now considered an effective congestion control mechanism for enhancing transport protocol performance over wireless links. In order to have good link utilization, it is necessary for queues to adapt to varying traffic loads. This paper considers a particular scheme which is called Adaptive AQM (AAQM and studies its performance in the presence of feedback delays and its ability to maintain a small queue length as well as its robustness in the presence of traffic burstiness. The paper also presents a method based on the well-known Markov Modulated Poisson Process (MPP to capture traffic burstiness and buffer occupancy. To demonstrate the generality of the presented method, an analytic model is described and verified by extensive simulations of different adaptive AQM algorithms. The analysis and simulations show that AAQM outperforms the other AQMs with respect to responsiveness and robustness.

  10. APPLICATION OF NEWTON RAPHSON ALGORITHM FOR OPTIMIZING TRANSMISSION CONTROL PROTOCOL PERFORMANCE

    Directory of Open Access Journals (Sweden)

    J. Viji Priya

    2013-01-01

    Full Text Available Wireless networks are growing rapidly. TCP is the most widely-used protocol on Internet and so optimizing TCP performance is very important for fast efficient data transfer. The different existing TCP variants and solutions they have not been analyzed together to identify the bottlenecks in wireless networks. TCP has a major problem in its congestion control algorithm which does not allow the flow to achieve the full available bandwidth on fast long-distance links. This problem has been studied in this study using a new high speed congestion control TCP protocol based on the Newton Raphson algorithm This study further analyses involving six TCP performance evaluation constraints namely, TCP full bandwidth utilization, throughput, packet loss rate, fairness in sharing bandwidth, friendliness in short-RTT and long-RTT and these constraints are used to evaluate the proposed Newton Raphson Congestion Control (NRC-TCP performance. This study shows that the proposed algorithm performs better compared with the other methods of application.

  11. A Survey of Congestion Control in Proactive Source Routing Protocol in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Bhagyashree S kayarkar

    2014-12-01

    Full Text Available In mobile ad hoc networks (MANET congestion can take place between the two intermediate nodes, when the packet is transferred from the source to the destination. The congestion in MANET is mainly due to frequent change to topology and high mobility of nodes, which lead to high loss of packet. In ad hoc network the congestion control techniques with TCP becomes difficult to handle since in ad hoc network there is high density of nodes in the network and there is frequent change to topology in the network. In this paper to control the congestion in proactive source routing protocol an error message is generated by the receiver to reduce the packet sending rate. We are using a new control message i.e., Packet Error Announcing Message called (PEAM messages.

  12. A Control Packet Minimized Routing Protocol for Ad-hoc Wireless Networks

    Directory of Open Access Journals (Sweden)

    Youn-Sik Hong

    2013-09-01

    Full Text Available AODV routing protocol is intended for use by mobile nodes in ad-hoc wireless networks. As the degree of node mobility becomes high, however, the number of RREQ and RREP messages during the route discovery process increase so rapidly. The unexpected increases in the number of control packets cause the destination node to decrease the packet receiving rate. Besides, the overall energy consumption for the network can be increased. Thus, we propose a novel method of adaptively controlling the occurrences of the control packets based on AIAD (additive increase additive decrease under a consideration of the current network status. We have tested our proposed method with both the conventional AODV and the method using timestamp based on the three performance metrics; i.e., node mobility, node velocity, and node density, to compare their performances.

  13. A SURVEY OF CONGESTION CONTROL IN PROACTIVE SOURCE ROUTING PROTOCOL IN MOBILE AD HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    Bhagyashree S kayarkar

    2015-10-01

    Full Text Available In mobile ad hoc networks (MANET congestion can take place between the two intermediate nodes, when the packet is transferred from the source to the destination. The congestion in MANET is mainly due to frequent change to topology and high mobility of nodes, which lead to high loss of packet. In ad hoc network the congestion control techniques with TCP becomes difficult to handle since in ad hoc network there is high density of nodes in the network and there is frequent change to topology in the network. In this paper to control the congestion in proactive source routing protocol an error message is generated by the receiver to reduce the packet sending rate. We are using a new control message i.e., Packet Error Announcing Message called (PEAM messages.

  14. Exploring the impact of a decision support intervention on vascular access decisions in chronic hemodialysis patients: study protocol

    Directory of Open Access Journals (Sweden)

    Donnelly Sandra

    2011-02-01

    Full Text Available Abstract Background In patients with Stage 5 Chronic Kidney Disease who require renal replacement therapy a major decision concerns modality choice. However, many patients defer the decision about modality choice or they have an urgent or emergent need of RRT, which results in them starting hemodialysis with a Central Venous Catheter. Thereafter, efforts to help patients make more timely decisions about access choices utilizing education and resource allocation strategies met with limited success resulting in a high prevalent CVC use in Canada. Providing decision support tailored to meet patients' decision making needs may improve this situation. The Registered Nurses Association of Ontario has developed a clinical practice guideline to guide decision support for adults living with Chronic Kidney Disease (Decision Support for Adults with Chronic Kidney Disease. The purpose of this study is to determine the impact of implementing selected recommendations this guideline on priority provincial targets for hemodialysis access in patients with Stage 5 CKD who currently use Central Venous Catheters for vascular access. Methods/Design A non-experimental intervention study with repeated measures will be conducted at St. Michaels Hospital in Toronto, Canada. Decisional conflict about dialysis access choice will be measured using the validated SURE tool, an instrument used to identify decisional conflict. Thereafter a tailored decision support intervention will be implemented. Decisional conflict will be re-measured and compared with baseline scores. Patients and staff will be interviewed to gain an understanding of how useful this intervention was for them and whether it would be feasible to implement more widely. Quantitative data will be analyzed using descriptive and inferential statistics. Statistical significance of difference between means over time for aggregated SURE scores (pre/post will be assessed using a paired t-test. Qualitative analysis

  15. "hCG priming" effect in controlled ovarian stimulation through a long protocol

    Directory of Open Access Journals (Sweden)

    Antsaklis Aris

    2009-08-01

    Full Text Available Abstract Background Recently, it has been demonstrated that, in patients down-regulated by GnRH analogues (GnRHa, a short-term pre-treatment with recombinant LH (rLH, prior to recombinant FSH (rFSH administration, increases the number of small antral follicle prior to FSH stimulation and the yield of normally fertilized embryos. However, no data exist in the literature regarding the potential beneficial effect of "hCG priming" in controlled ovarian hyperstimulation (COH through a long GnRH-a protocol, which binds the same receptor (LH/hCGR, though it is a much more potent compared to LH. The primary aims of this study were to assess the effect of short-term pre-rFSH administration of hCG in women entering an ICSI treatment cycle on follicular development, quality of oocytes and early embryo development. The secondary endpoints were to record the effects on endometrial quality and pregnancy rate. Methods Patients with a history of at least one previous unsuccessful ICSI cycle were randomly assigned into two groups to receive treatment with either a long protocol with rFSH (control group or a long protocol with rFSH and pre-treatment with hCG (hCG group. In particular, in the latter group, a fixed 7 days course of 200 IU/day hCG was administered as soon as pituitary desensitization was confirmed. Results The mean number of oocytes retrieved was not significantly different between the two treatment groups, although the percentage of mature oocytes tended to be higher but not significantly different in hCG-treated patients. The percentage of patients with more than one grade 3 embryos was higher in the pre-treatment group, which also showed a higher pregnancy rate. Conclusion All the above clinical observations, in conjunction with previous data, suggest a point towards a beneficial "hCG priming" effect in controlled ovarian hyperstimulation through a long GnRH-a down-regulation protocol, particularly in patients with previous ART failures.

  16. Fertility effects of abortion and birth control pill access for minors.

    Science.gov (United States)

    Guldi, Melanie

    2008-11-01

    This article empirically assesses whether age-restricted access to abortion and the birth control pill influence minors' fertility in the United States. There is not a strong consensus in previous literature regarding the relationship between laws restricting minors' access to abortion and minors' birth rates. This is the first study to recognize that state laws in place prior to the 1973 Roe v. Wade decision enabled minors to legally consent to surgical treatment-including abortion-in some states but not in others, and to construct abortion access variables reflecting this. In this article, age-specific policy variables measure either a minor's legal ability to obtain an abortion or to obtain the birth control pill without parental involvement. I find fairly strong evidence that young women's birth rates dropped as a result of abortion access as well as evidence that birth control pill access led to a drop in birth rates among whites.

  17. A cluster-randomized trial of task shifting and blood pressure control in Ghana: study protocol

    OpenAIRE

    Ogedegbe, Gbenga; Plange-Rhule, Jacob; Gyamfi, Joyce; Chaplin, William; Ntim, Michael; Apusiga, Kingsley; Khurshid, Kiran; Cooper, Richard

    2014-01-01

    Background Countries in sub-Saharan Africa (SSA) are experiencing an epidemic of cardiovascular disease (CVD) propelled by rapidly increasing rates of hypertension. Barriers to hypertension control in SSA include poor access to care and high out-of-pocket costs. Although SSA bears 24% of the global disease burden, it has only 3% of the global health workforce. Given such limited resources, cost-effective strategies, such as task shifting, are needed to mitigate the rising CVD epidemic in SSA....

  18. Traumatic Brain Injury in Latin America: Lifespan Analysis Randomized Control Trial Protocol

    Science.gov (United States)

    Chesnut, Randall M.; Temkin, Nancy; Carney, Nancy; Dikmen, Sureyya; Pridgeon, Jim; Barber, Jason; Celix, Juanita M.; Chaddock, Kelley; Cherner, Marianna; Hendrix, Terence; Lujan, Silvia; Machamer, Joan; Petroni, Gustavo; Rondina, Carlos; Videtta, Walter

    2012-01-01

    Background Although in the developed world the intracranial pressure (ICP) monitor is considered “standard of care” for patients with severe traumatic brain injury (TBI), its usefulness to direct treatment decisions has never been tested rigorously. Objective The primary focus is to conduct a high quality randomized, controlled trial to determine if ICP monitoring used to direct TBI treatment improves patient outcomes. By providing education, equipment, and structure, the project will enhance the research capacity of the collaborating investigators and will foster the collaborations established during earlier studies (add refs to papers from earlier studies). Methods Study centers were selected that routinely treated ICP based on clinical examination and CT imaging using internal protocols. We randomize patients to either an ICP Monitor Group or an Imaging and Clinical Examination Group. Treatment decisions for the ICP Monitor Group are guided by ICP monitoring, based on established guidelines. Treatment decisions for the Imaging and Clinical Examination Group are made using a single protocol derived from those previously being used at those centers. Expected Outcomes There are two study hypotheses: 1) Patients with severe TBI whose acute care treatment is managed using ICP monitors will have improved outcomes and 2) incorporating ICP monitoring into the care of patients with severe TBI will minimize complications and decrease length of ICU stay. Discussion This clinical trial tests the effectiveness of a management protocol based on technology considered pivotal to brain trauma treatment in the developed world - the ICP monitor. A randomized controlled trial of ICP monitoring has never been performed - a critical gap in the evidence base that supports the role of ICP monitoring in TBI care. As such, the results of this RCT will have global implications regardless of the level of development of the trauma system. PMID:22986600

  19. Assessment of current practices in creating and using passwords as a control mechanism for information access

    Directory of Open Access Journals (Sweden)

    P. L. Wessels

    2007-11-01

    Full Text Available One of the critical issues in managing information within an organization is to ensure that proper controls exist and are applied in allowing people access to information. Passwords are used extensively as the main control mechanism to identify users wanting access to systems, applications, data files, network servers or personal information. In this article, the issues involved in selecting and using passwords are discussed and the current practices employed by users in creating and storing passwords to gain access to sensitive information are assessed. The results of this survey conclude that information managers cannot rely only on users to employ proper password control in order to protect sensitive information.

  20. A Distributed Architecture for Sharing Ecological Data Sets with Access and Usage Control Guarantees

    DEFF Research Database (Denmark)

    Bonnet, Philippe; Gonzalez, Javier; Granados, Joel Andres

    2014-01-01

    and usage control is necessary to enforce existing open data policies. We have proposed the vision of trusted cells: A decentralized infrastructure, based on secure hardware running on devices equipped with trusted execution environments at the edges of the Internet. We originally described the utilization...... new insights, there are signicant barriers to the realization of this vision. One of the key challenge is to allow scientists to share their data widely while retaining some form of control over who accesses this data (access control) and more importantly how it is used (usage control). Access...... data sets with access and usage control guarantees. We rely on examples from terrestrial research and monitoring in the arctic in the context of the INTERACT project....

  1. Computer Program Development Specification Terminal Access Controller. Appendix B. Access Line Modes.

    Science.gov (United States)

    1979-04-06

    CG-510262 Part 1 of 2 6 April 1979 Page B17 iS U £ 44 0 o a, U, 00 0 ,.- C 2 50 St -: 2-, CG-510262 Part 1 of 2 6 April 1979 Page B18 00 0 0 0 4 4 0...receipt of RM as the response to a block and acknowledged wit , receive control character ACK2. CAN is never transmitted wit’iin t-ne text portion of a

  2. Efficacy of smoking prevention program 'Smoke-free Kids': study protocol of a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    van Schayck Onno CP

    2009-12-01

    Full Text Available Abstract Background A strong increase in smoking is noted especially among adolescents. In the Netherlands, about 5% of all 10-year olds, 25% of all 13-year olds and 62% of all 17-year olds report ever smoking. In the U.S., an intervention program called 'Smoke-free Kids' was developed to prevent children from smoking. The present study aims to assess the effects of this home-based smoking prevention program in the Netherlands. Methods/Design A randomized controlled trial is conducted among 9 to 11-year old children of primary schools. Participants are randomly assigned to the intervention and control conditions. The intervention program consists of five printed activity modules designed to improve parenting skills specific to smoking prevention and parent-child communication regarding smoking. These modules will include additional sheets with communication tips. The modules for the control condition will include solely information on smoking and tobacco use. Initiation of cigarette smoking (first instance of puffing on a lighted cigarette, susceptibility to cigarette smoking, smoking-related cognitions, and anti-smoking socialization will be the outcome measures. To collect the data, telephone interviews with mothers as well as with their child will be conducted at baseline. Only the children will be examined at post-intervention follow-ups (6, 12, 24, and 36 months after the baseline. Discussion This study protocol describes the design of a randomized controlled trial that will evaluate the effectiveness of a home-based smoking prevention program. We expect that a significantly lower number of children will start smoking in the intervention condition compared to control condition as a direct result of this intervention. If the program is effective, it is applicable in daily live, which will facilitate implementation of the prevention protocol. Trial registration Netherlands Trial Register NTR1465

  3. Dry needling in a manual physiotherapy and therapeutic exercise protocol for patients with chronic mechanical shoulder pain of unspecific origin: a protocol for a randomized control trial.

    Science.gov (United States)

    Tejera-Falcón, Emma; Toledo-Martel, Nuria Del Carmen; Sosa-Medina, Francisco Manuel; Santana-González, Fátima; Quintana-de la Fe, Miriam Del Pino; Gallego-Izquierdo, Tomás; Pecos-Martín, Daniel

    2017-09-18

    Shoulder pain of musculoskeletal origin is the main cause of upper limb pain of non-traumatic origin. Despite being one of the most common reasons for consultation, there is no established protocol for treatment due to the complexity of its etiology. However, it has been shown that the presence of myofascial trigger points on the shoulder muscles is a common condition associated with patients suffering from shoulder pain. This protocol has been created which describes the design of a randomized controlled trial to evaluate the effectiveness of the inclusion of dry needling (DN) within a protocol of manual physiotherapy and therapeutic exercise in the treatment of chronic shoulder pain of unspecific origin. Thirty-six participants aged 18-65 years will be recruited having mechanical chronic shoulder pain on unspecific origin and meeting the inclusion criteria. These will be randomized to one of two interventions, (i) DN, manual physiotherapy and therapeutic exercise or (ii) sham DN, manual physiotherapy and therapeutic exercise. The protocol will cover 6 weeks of treatment, with a 6-month follow-up. Our main outcome measure will be the Visual Analogue Scale for pain. This is the first study to combine the use of DN, manual physiotherapy and an exercise program with a 6-month follow-up, thus becoming a new contribution to the treatment of chronic shoulder pain, while new lines of research may be established to help determine the effects of DN on chronic shoulder pain and the frequency and proper dosage. International Standard Randomized Controlled Trial Number Register: ISRCTN30604244 ( http://www.controlled-trials.com ) 29 June 2016.

  4. Implementation of the quality control protocol in Crawls; Puesta en marcha del protocolo de control de calidad en rastreos

    Energy Technology Data Exchange (ETDEWEB)

    Ambroa Rey, E. M.; Gimenez Insua, M.; Vazquez Vazquez, R.; Sanchez Garcia, M.; Luna Vega, V.; Mosquera Suero, J.; Otero Martinez, C.; Lobato Busto, R.; Pombar Camean, M.

    2013-07-01

    Bone scintigraphy is a test widely used in Nuclear Medicine of our service. 33% of the tests performed are of this type, so it is necessary to develop a specific quality control protocol for the tracking of the gamma camera acquisitions. This type of procurement means the mechanical movement of the stretcher, with a static initial phase in which the movement of the stretcher is replaced by the gradual opening of the field of view (electronic window). This creates the density of accounts to be uniform throughout the study. The presence of a movement mechanical and co-registration with the static phase implies the need for specific tests. (Author)

  5. Enhancing Subject Access to OPACs: Controlled Vocabulary vs. Natural Language.

    Science.gov (United States)

    Cousins, Shirley Anne

    1992-01-01

    Investigation of retrieval performance of controlled vocabulary derived from natural language terms in tables of contents and book indexes assumed that controlled vocabulary representative of users' queries should adequately represent documents' contents. Queries were indexed using Library of Congress Subject Headings (LSCH), Dewey Decimal…

  6. The role of user's perceived control in interface design, employing verbal protocol analysis.

    Science.gov (United States)

    Robson, J I; Crellin, J M

    1989-12-01

    This paper outlines some general strengths and weaknesses of using psychological theoretical approaches beyond their original domains, focusing on Rotter's (1966) Internal and External (I/E) Locus of Control construct. Rotter's theory examines perceived locus of control of individuals during their social interactions. The issues of why and how I/E may be a useful theoretical approach to human-computer interaction (HCI) are addressed. Specific problems encountered in importing I/E into HCI are then described. An interface evaluation experiment is discussed. First, the system used for evaluation purposes is described, as well as the verbal protocol technique used, and the methods of analysis. Finally, the conclusions about the interface are presented. In this contact, I/E as an interface evaluation tool is discussed, as are related issues of importing psychological theories into HCI.

  7. A Secure Time-Stamp Based Concurrency Control Protocol For Distributed Databases

    Directory of Open Access Journals (Sweden)

    Shashi Bhushan

    2007-01-01

    Full Text Available In distributed database systems the global database is partitioned into a collection of local databases stored at different sites. In this era of growing technology and fast communication media, security has an important role to play. In this paper we presented a secure concurrency control protocol (SCCP based on the timestamp ordering, which provides concurrency control and maintains security. We also implemented SCCP and a comparison of SCCP is presented in three cases (High, Medium and Low security levels. In this experiment, It is observed that throughput of the system decreases as the security level of the transaction increases, i.e., there is tradeoff between the security level and the throughput of the system.

  8. Development of SRS.php, a Simple Object Access Protocol-based library for data acquisition from integrated biological databases.

    Science.gov (United States)

    Barbosa-Silva, A; Pafilis, E; Ortega, J M; Schneider, R

    2007-12-11

    Data integration has become an important task for biological database providers. The current model for data exchange among different sources simplifies the manner that distinct information is accessed by users. The evolution of data representation from HTML to XML enabled programs, instead of humans, to interact with biological databases. We present here SRS.php, a PHP library that can interact with the data integration Sequence Retrieval System (SRS). The library has been written using SOAP definitions, and permits the programmatic communication through webservices with the SRS. The interactions are possible by invoking the methods described in WSDL by exchanging XML messages. The current functions available in the library have been built to access specific data stored in any of the 90 different databases (such as UNIPROT, KEGG and GO) using the same query syntax format. The inclusion of the described functions in the source of scripts written in PHP enables them as webservice clients to the SRS server. The functions permit one to query the whole content of any SRS database, to list specific records in these databases, to get specific fields from the records, and to link any record among any pair of linked databases. The case study presented exemplifies the library usage to retrieve information regarding registries of a Plant Defense Mechanisms database. The Plant Defense Mechanisms database is currently being developed, and the proposal of SRS.php library usage is to enable the data acquisition for the further warehousing tasks related to its setup and maintenance.

  9. Multi-channel MAC Protocol in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Yongli Sun

    2013-11-01

    Full Text Available Since cognitive wireless network (CRN has the characteristic of secondary use, it can enable the device to dynamically access available spectrum without interference to primary users (PUs, which can effectively alleviate contradiction between the lack of spectrum resources and the growing demand for wireless access. However, Medium Access Control (MAC protocol as CRN core components, can achieve competition access of the licensed spectrum and coordination control, which will maximize spectrum utilization efficiency and network throughput. The contribution of this survey is threefold. First, we analyze the characteristics of the existed multi- channel MAC protocol in CRN; Second, according to the different ways of spectrum access in CRNs, the multi-channel MAC protocols are classified into time-slotted based MAC protocol, control channel based MAC protocol and hybrid MAC protocol, and the paper emphatically analyzed the advantages and disadvantages of these multi-channel MAC protocols; Finally, the paper explores the difficulties and the challenges of multi-channel MAC protocols design in cognitive wireless network.

  10. An accessible protocol for solid-phase extraction of N-linked glycopeptides through reductive amination by amine-functionalized magnetic nanoparticles.

    Science.gov (United States)

    Zhang, Ying; Kuang, Min; Zhang, Lijuan; Yang, Pengyuan; Lu, Haojie

    2013-06-04

    In light of the significance of glycosylation for wealthy biological events, it is important to prefractionate glycoproteins/glycopeptides from complex biological samples. Herein, we reported a novel protocol of solid-phase extraction of glycopeptides through a reductive amination reaction by employing the easily accessible 3-aminopropyltriethoxysilane (APTES)-functionalized magnetic nanoparticles. The amino groups from APTES, which were assembled onto the surface of the nanoparticles through a one-step silanization reaction, could conjugate with the aldehydes from oxidized glycopeptides and, therefore, completed the extraction. To the best of our knowledge, this is the first example of applying the reductive amination reaction into the isolation of glycopeptides. Due to the elimination of the desalting step, the detection limit of glycopeptides was improved by 2 orders of magnitude, compared to the traditional hydrazide chemistry-based solid phase extraction, while the extraction time was shortened to 4 h, suggesting the high sensitivity, specificity, and efficiency for the extraction of N-linked glycopeptides by this method. In the meantime, high selectivity toward glycoproteins was also observed in the separation of Ribonuclease B from the mixtures contaminated with bovine serum albumin. What's more, this technique required significantly less sample volume, as demonstrated in the successful mapping of glycosylation of human colorectal cancer serum with the sample volume as little as 5 μL. Because of all these attractive features, we believe that the innovative protocol proposed here will shed new light on the research of glycosylation profiling.

  11. 77 FR 26789 - Certain Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and...

    Science.gov (United States)

    2012-05-07

    ... From the Federal Register Online via the Government Publishing Office ] INTERNATIONAL TRADE COMMISSION Certain Semiconductor Chips Having Synchronous Dynamic Random Access Memory Controllers and Products Containing Same; Determination Rescinding the Exclusion Order and Cease and Desist Orders...

  12. Role-Based Access Control for the Large Hadron Collider at CERN

    CERN Document Server

    Yastrebov, I

    2010-01-01

    Large Hadron Collider (LHC) is the largest scientific instrument ever created. It was built with the intention of testing the most extreme conditions of the matter. Taking into account the significant dangers of LHC operations, European Organization for Nuclear Research (CERN) has developed multi-pronged approach for machine safety, including access control system. This system is based on role-based access control (RBAC) concept. It was designed to protect from accidental and unauthorized access to the LHC and injector equipment. This paper introduces the new model of the role-based access control developed at CERN and gives detailed mathematical description of it. We propose a new technique called dynamic authorization that allows deploying RBAC gradually in the large systems. Moreover, we show how the protection for the very large distributed equipment control system may be implemented in efficient way. This paper also describes motivation of the project, requirements and overview of the main components: au...

  13. The Design of the M-B-Quadro Optical Switch and Its Access Control Strategies

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper proposes a new simple contention resolution switching architecture, M-B-Quadro, and its underlying access control strategies. By incorporating delay and buffer lines, the switching node can effectively obtain very low packet deflection probability.

  14. Access 3 project protocol: young people and health system navigation in the digital age: a multifaceted, mixed methods study.

    Science.gov (United States)

    Kang, Melissa; Robards, Fiona; Sanci, Lena; Steinbeck, Katharine; Jan, Stephen; Hawke, Catherine; Kong, Marlene; Usherwood, Tim

    2017-08-07

    The integration of digital technology into everyday lives of young people has become widespread. It is not known whether and how technology influences barriers and facilitators to healthcare, and whether and how young people navigate between face-to-face and virtual healthcare. To provide new knowledge essential to policy and practice, we designed a study that would explore health system access and navigation in the digital age. The study objectives are to: (1) describe experiences of young people accessing and navigating the health system in New South Wales (NSW), Australia; (2) identify barriers and facilitators to healthcare for young people and how these vary between groups; (3) describe health system inefficiencies, particularly for young people who are marginalised; (4) provide policy-relevant knowledge translation of the research data. This mixed methods study has four parts, including: (1) a cross-sectional survey of young people (12-24 years) residing in NSW, Australia; (2) a longitudinal, qualitative study of a subsample of marginalised young people (defined as young people who: identify as Aboriginal and/or Torres Strait Islander; are experiencing homelessness; identify as sexuality and/or gender diverse; are of refugee or vulnerable migrant background; and/or live in rural or remote NSW); (3) interviews with professionals; (4) a knowledge translation forum. Ethics approvals were sought and granted. Data collection commenced in March 2016 and will continue until June 2017. This study will gather practice and policy-relevant intelligence about contemporary experiences of young people and health services, with a unique focus on five different groups of marginalised young people, documenting their experiences over time. Access 3 will explore navigation around all levels of the health system, determine whether digital technology is integrated into this, and if so how, and will translate findings into policy-relevant recommendations. © Article author(s) (or

  15. The mPED randomized controlled clinical trial: applying mobile persuasive technologies to increase physical activity in sedentary women protocol

    Directory of Open Access Journals (Sweden)

    Fukuoka Yoshimi

    2011-12-01

    Full Text Available Abstract Background Despite the significant health benefits of regular physical activity, approximately half of American adults, particularly women and minorities, do not meet the current physical activity recommendations. Mobile phone technologies are readily available, easily accessible and may provide a potentially powerful tool for delivering physical activity interventions. However, we need to understand how to effectively apply these mobile technologies to increase and maintain physical activity in physically inactive women. The purpose of this paper is to describe the study design and protocol of the mPED (mobile phone based physical activity education randomized controlled clinical trial that examines the efficacy of a 3-month mobile phone and pedometer based physical activity intervention and compares two different 6-month maintenance interventions. Methods A randomized controlled trial (RCT with three arms; 1 PLUS (3-month mobile phone and pedometer based physical activity intervention and 6-month mobile phone diary maintenance intervention, 2 REGULAR (3-month mobile phone and pedometer based physical activity intervention and 6-month pedometer maintenance intervention, and 3 CONTROL (pedometer only, but no intervention will be conducted. A total of 192 physically inactive women who meet all inclusion criteria and successfully complete a 3-week run-in will be randomized into one of the three groups. The mobile phone serves as a means of delivering the physical activity intervention, setting individualized weekly physical activity goals, and providing self-monitoring (activity diary, immediate feedback and social support. The mobile phone also functions as a tool for communication and real-time data capture. The primary outcome is objectively measured physical activity. Discussion If efficacy of the intervention with a mobile phone is demonstrated, the results of this RCT will be able to provide new insights for current behavioral

  16. Access Control in the ATLAS TDAQ Online Cluster

    CERN Document Server

    Leahu, Marius Constantin; Stoichescu, D A; Lehmann Miotto, G

    ATLAS (A Toroidal LHC Apparatus) is a general-purpose detector for studying high-energy particle interactions: it is the largest particle detector experiment at CERN and it is built around one of the interaction points of the proton beams accelerated by the Large Hadron Collider (LHC). The detector generates an impressive amount of raw data: 64 TB per second as a result of 40 MHz proton-proton collision rate with 1.6 MB data for each such event. The handling of such data rate is managed by a three levels Trigger and Data Acquisition (TDAQ) system, which filters out the events not relevant from physics research point of view and selects in the end in the order of 1000 events per second to be stored for offline analyses. This system comprises a significant number of hardware devices, software applications and human personnel to supervise the experiment operation. Their protection against damages as a result of misuse and their optimized exploitation by avoiding the conflicting accesses to resources are key requ...

  17. Smart packet access and call admission control for efficient resource management in advanced wireless networks

    OpenAIRE

    Phan, V. V. (Vinh V.)

    2005-01-01

    Abstract Efficient management of rather limited resources, including radio spectrum and mobile-terminal battery power, has been the fundamental design challenge of wireless networks and one of the most widespread research problems over the years. MAC (Medium Access Control) for packet access and CAC (Call Admission Control) for connection-oriented service domains are commonly used as effective tools to manage radio resources, capacity and performance of wireless networks while providing ad...

  18. Springfield Processing Plant* (A Hypothetical Facility) SPP, Entry Control Point and Vehicle Gate Access Control Post Order

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Gregory A. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2014-06-01

    This hypothetical order provides the requirements and instructions for the Springfield Processing Plant (SPP) Vehicle Gate and Entry Control Point (ECP) in the perimeter access building. The purpose of this post is to prevent the theft, sabotage or diversion of nuclear material (NM), control access and exit at the protected area, and to respond to emergencies according the SPP Guard Force (GF) Contingency Plan and as directed by a Guard Force Supervisor.

  19. TEMPORAL, DELEGABLE AND CHEAP UPDATE ACCESS CONTROL TO PUBLISHED XML DOCUMENTS

    Directory of Open Access Journals (Sweden)

    Waleed Halboob

    2013-01-01

    Full Text Available Providing access control for published XML documents on the Web is an important topic. It involves the use of cryptographic techniques, addressing different requirements and, as a result, facing several challenges. Existing solutions still have some weaknesses such as system update cost, number of required secret encryption/decryption keys, size of encrypted document and supporting temporal and delegable access. This study propose a push--based access control policy enforcement mechanism for addressing these issues using a Dynamic Key Management Table (DKMT and based on Identity Based Encryption (IBE. The proposed mechanism addresses the existing challenges and provides a more acceptable solution.

  20. Unifying the Access Control Mechanism for the Enterprises Using XACML Policy Levels

    Directory of Open Access Journals (Sweden)

    N. Senthil Kumar

    2015-11-01

    Full Text Available —Many enterprises have intended to promote their applications with stern access control mechanism and yield the stringent authorization deployment in their individual proprietary manner. The development of this build up will result in tight coupling of authorization mechanisms within the enterprise applications. In many enterprises setup, the implicit authorization processes are embedded within the application and promote error prone accessing of requested policies. This sort of embedded authorization will let the users to carry out the specific actions without knowing the access control policy as well as its embedded setup with the help of third party involvement. But this approach has some serious effects in controlling the issues such as skipping the trust based applications, violates the policy setups and pave the way to exploit the authorized data to the end users. Many enterprises had faced serious problem in controlling its sensitive data from this implicit authorization decisions and hence decided to develop a security mechanism which can be totally controlled by centralized way of access policy. Therefore, the eXtensible Access Control Markup Language (XACML provides a very simple and powerful remedy for authorization mechanism and for the access policy set ups.