WorldWideScience

Sample records for access control protocols

  1. Studying Media Access andControl Protocols

    Mohammed, Alalelddin Fuad Yousif

    2010-01-01

    This thesis project’s goal is to enable undergraduate students to gain insight into media access and control protocols based upon carrying out laboratory experiments. The educational goal is to de-mystifying radio and other link and physical layer communication technologies as the students can follow packets from the higher layers down through the physical layer and back up again. The thesis fills the gap between the existing documentation for the Universal Software Radio Peripheral (USRP) re...

  2. Hopping control channel MAC protocol for opportunistic spectrum access networks

    FU Jing-tuan; JI Hong; MAO Xu

    2010-01-01

    Opportunistic spectrum access (OSA) is considered as a promising approach to mitigate spectrum scarcity by allowing unlicensed users to exploit spectrum opportunities in licensed frequency bands. Derived from the existing channel-hopping multiple access (CHMA) protocol,we introduce a hopping control channel medium access control (MAC) protocol in the context of OSA networks. In our proposed protocol,all nodes in the network follow a common channel-hopping sequence; every frequency channel can be used as control channel and data channel. Considering primary users' occupancy of the channel,we use a primary user (PU) detection model to calculate the channel availability for unlicensed users' access. Then,a discrete Markov chain analytical model is applied to describe the channel states and deduce the system throughput. Through simulation,we present numerical results to demonstrate the throughput performance of our protocol and thus validate our work.

  3. Adaptive Medium Access Control Protocol for Wireless Body Area Networks

    Javaid, N.; Ahmad, A.; A. Rahim; Z.A. Khan; M. Ishfaq; Qasim, U.

    2014-01-01

    Wireless Body Area Networks (WBANs) are widely used for applications such as modern health-care systems, where wireless sensors (nodes) monitor the parameter(s) of interest. Nodes are provided with limited battery power and battery power is dependent on radio activity. MAC protocols play a key role in controlling the radio activity. Therefore, we present Adaptive Medium Access Control (A-MAC) protocol for WBANs supported by linear programming models for the minimization of energy consumption ...

  4. Control with a random access protocol and packet dropouts

    Wang, Liyuan; Guo, Ge

    2016-08-01

    This paper investigates networked control systems whose actuators communicate with the controller via a limited number of unreliable channels. The access to the channels is decided by a so-called group random access protocol, which is modelled as a binary Markov sequence. Data packet dropouts in the channels are modelled as independent Bernoulli processes. For such systems, a systematic characterisation for controller synthesis is established and stated in terms of the transition probabilities of the Markov protocol and the packet dropout probabilities. The results are illustrated via a numerical example.

  5. Efficient medium access control protocol for geostationary satellite systems

    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.

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

    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.

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

    Abdul Razaque; Elleithy, Khaled M.

    2014-01-01

    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,...

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

    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.

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

    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...

  10. Concurrency control and recovery on lightweight directory access protocol

    Potnis, Rohit R.; Sathaye, Archana S.

    2003-04-01

    In this paper we provide a concurrency control and recovery (CCR) mechanism over cached LDAP objects. An LDAP server can be directly queried using system calls to retrieve data. Existing LDAP implementations do not provide CCR mechanisms. In such cases, it is up to the application to verify that accesses remain serialized. Our mechanism provides an independent layer over an existing LDAP server (Sun One Directory Server), which handles all user requests, serializes them based on 2 Phase Locking and Timestamp Ordering mechanisms and provides XML-based logging for recovery management. Furthermore, while current LDAP servers only provide object-level locking, our scheme serializes transactions on individual attributes of LDAP objects (attribute-level locking). We have developed a Directory Enabled Network (DEN) Simulator that operates on a subset of directory objects on an existing LDAP server to test the proposed mechanism. We perform experiments to show that our mechanism can gracefully address concurrency and recovery related issues over and LDAP server.

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

    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.

  12. Broadband passive optical network media access control protocols

    Quayle, Alan

    1996-11-01

    Most telecommunication operators are currently deciding on how to respond to customers' needs stimulated by the synergy between compression coding of multimedia and the emergence of broadband digital networks. This paper describes a range of broadband access architectures under consideration in the full services access network initiative. All architectures have a common requirement for a broadband ATM PON. A common broadband PON applicable to many operators increases the world-wide market for the product. With greater production volumes manufacturers' costs reduce because of the experience curve effect making broadband access systems economic.

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

    Elvio João Leonardo; Ailton Akira Shinoda

    2004-01-01

    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 “...

  14. Cater: an Opportunistic Medium Access Control Protocol for Wireless Local Area Networks

    Mullins, Barry E.

    1997-01-01

    An adaptive MAC protocol is developed and analyzed that offers a "best case" scenario by allowing the MAC to control medium parameters thereby fully exploiting the channel of an ad hoc wireless LAN. This new, opportunistic medium access control protocol is called CATER (Code Adapts To Enhance Reliability) and is based on the proposed MAC standard for wireless local area networks (WLAN)-IEEE 802.11 [IEE96]. As currently proposed, IEEE 802.11 uses a fixed pseudo-noise (PN) code for spreading ...

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

    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.

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

    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.

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

    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.

  18. A stochastic control approach to Slotted-ALOHA random access protocol

    Pietrabissa, Antonio

    2013-12-01

    ALOHA random access protocols are distributed protocols based on transmission probabilities, that is, each node decides upon packet transmissions according to a transmission probability value. In the literature, ALOHA protocols are analysed by giving necessary and sufficient conditions for the stability of the queues of the node buffers under a control vector (whose elements are the transmission probabilities assigned to the nodes), given an arrival rate vector (whose elements represent the rates of the packets arriving in the node buffers). The innovation of this work is that, given an arrival rate vector, it computes the optimal control vector by defining and solving a stochastic control problem aimed at maximising the overall transmission efficiency, while keeping a grade of fairness among the nodes. Furthermore, a more general case in which the arrival rate vector changes in time is considered. The increased efficiency of the proposed solution with respect to the standard ALOHA approach is evaluated by means of numerical simulations.

  19. A Study of Medium Access Control Protocols for Wireless Body Area Networks

    Ullah, Sana; Shen, Bin; Islam, S.M. Riazul; Khan, Pervez; Saleem, Shahnaz; Kwak, Kyung Sup

    2010-01-01

    The seamless integration of low-power, miniaturised, invasive/non-invasive lightweight sensor nodes have contributed to the development of a proactive and unobtrusive Wireless Body Area Network (WBAN). A WBAN provides long-term health monitoring of a patient without any constraint on his/her normal dailylife activities. This monitoring requires low-power operation of invasive/non-invasive sensor nodes. In other words, a power-efficient Medium Access Control (MAC) protocol is required to satis...

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

    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.

  1. Cooperative Medium Access Control Protocol for Mobile Ad-hoc Networks using Spatial Diversity

    Tazeem Ahmad Khan

    2013-10-01

    Full Text Available Enhancement the Performance of MANET (Mobile Ad-hoc Network using spatial diversity. Spatial diversity implemented using cooperative transmission technique in Medium access control (MAC layer level protocol. In noisy environment limit the network performance like coverage area, limit number of node, degrade packet transmission rate, increase packet loss rate etc. In this paper enhance the source to destination transmission range, minimize the packet loss, improve packet transmission rate and appropriate end to end delay. When direct link is fail to transmit packet then Cooperative scheme help to transmit packet. Cooperative scheme is to help the packet transmission with five handshakes instead of four. This scheme implemented in MANET network on MAC layer protocol. Cooperative scheme improve the performance with help of intermediate node between sources to destination. We are performance analysis using discrete simulator NS-2 in MANET. Our performance based on MAC layer level with cooperative scheme in IEEE WLAN standard CSMA/CA protocol.

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

    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.

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

    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

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

    Razaque, Abdul; Elleithy, Khaled M

    2014-01-01

    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

  5. A Cloud-Assisted Random Linear Network Coding Medium Access Control Protocol for Healthcare Applications

    Kartsakli, Elli; Antonopoulos, Angelos; Alonso, Luis; Verikoukis, Christos

    2014-01-01

    Relay sensor networks are often employed in end-to-end healthcare applications to facilitate the information flow between patient worn sensors and the medical data center. Medium access control (MAC) protocols, based on random linear network coding (RLNC), are a novel and suitable approach to efficiently handle data dissemination. However, several challenges arise, such as additional delays introduced by the intermediate relay nodes and decoding failures, due to channel errors. In this paper, we tackle these issues by adopting a cloud architecture where the set of relays is connected to a coordinating entity, called cloud manager. We propose a cloud-assisted RLNC-based MAC protocol (CLNC-MAC) and develop a mathematical model for the calculation of the key performance metrics, namely the system throughput, the mean completion time for data delivery and the energy efficiency. We show the importance of central coordination in fully exploiting the gain of RLNC under error-prone channels. PMID:24618727

  6. A Study of Medium Access Control Protocols for Wireless Body Area Networks

    Ullah, Sana; Islam, S M Riazul; Khan, Pervez; Saleem, Shahnaz; Kwak, Kyung Sup; 10.3390/s100100128

    2010-01-01

    The seamless integration of low-power, miniaturised, invasive/non-invasive lightweight sensor nodes have contributed to the development of a proactive and unobtrusive Wireless Body Area Network (WBAN). A WBAN provides long-term health monitoring of a patient without any constraint on his/her normal dailylife activities. This monitoring requires low-power operation of invasive/non-invasive sensor nodes. In other words, a power-efficient Medium Access Control (MAC) protocol is required to satisfy the stringent WBAN requirements, including low-power consumption. In this paper, we first outline the WBAN requirements that are important for the design of a low-power MAC protocol. Then we study low-power MAC protocols proposed/investigated for a WBAN with emphasis on their strengths and weaknesses. We also review different power-efficient mechanisms for a WBAN. In addition, useful suggestions are given to help the MAC designers to develop a low-power MAC protocol that will satisfy the stringent WBAN requirements.

  7. An energy-efficient media access control protocol for chain-type wireless sensor networks

    Wang, Yu; Chen, Chang Wen

    2005-06-01

    We present in this paper an energy efficient media access control (MAC) protocol for chain-type wireless sensor networks. The chain-type sensor networks are fundamentally different from traditional sensor networks in that the sensor nodes in this class of networks are deployed along narrow and elongated geographical areas and form a chain-type topology. Recently, we have successfully developed hierarchical network architecture, sensor deployment strategy, and corresponding network initialization and operation protocols for this class of sensor networks. In this paper, we present a novel TDMA scheduling protocol that takes full advantages of the available channel reuse inherent in the chain-type sensor networks to develop energy efficient and high data throughput MAC protocols for sensor data transmission. The synchronized TDMA scheduling allows the nodes to power on only when it is scheduled to send and receive and therefore results in additional energy saving. Within a cluster, parallel transmission is made possible because of the linear distribution of nodes within the chain-type topology and this yields the desired high throughput. Preliminary simulations have been carried out to show that the proposed TDMA scheduling outperforms the well-know SMAC scheme in terms of energy efficiency and data throughput under various duty cycles.

  8. Control protocol: the proposed new CERN standard access procedure to accelerator equipment

    Control protocol provides a normalized access procedure for equipment of the same kind from a control system. Modelisation and the subsequent identification of functionalities with their parameters, variables and attributes have now been carried out at CERN for representative families of devices. ISO specifications, such as the ASN.1 metalanguage for data structure representation and MMS definitions and services have, to some extent, been introduced in the design for generality and compatibility with external world. The final product of this design is totally independent of the control systems and permits object oriented implementations in any controls frame. The present paper describes the different phases of the project with a short overview of the various implementations under development at CERN. (author)

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

    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...

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

    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.

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

    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.

  12. Bearer channel control protocol for the dynamic VB5.2 interface in ATM access networks

    Fragoulopoulos, Stratos K.; Mavrommatis, K. I.; Venieris, Iakovos S.

    1996-12-01

    In the multi-vendor systems, a customer connected to an Access network (AN) must be capable of selecting a specific Service Node (SN) according to the services the SN provides. The multiplicity of technologically varying AN calls for the definition of a standard reference point between the AN and the SN widely known as the VB interface. Two versions are currently offered. The VB5.1 is simpler to implement but is not as flexible as the VB5.2, which supports switched connections. The VB5.2 functionality is closely coupled to the Broadband Bearer Channel Connection Protocol (B-BCCP). The B-BCCP is used for conveying the necessary information for dynamic resource allocation, traffic policing and routing in the AN as well as for information exchange concerning the status of the AN before a new call is established by the SN. By relying on such a protocol for the exchange of information instead of intercepting and interpreting signalling messages in the AN, the architecture of the AN is simplified because the functionality related to processing is not duplicated. In this paper a prominent B- BCCP candidate is defined, called the Service node Access network Interaction Protocol.

  13. A Review on Medium Access Control Protocols for Wireless Sensor Networks

    Rakesh Bisht

    2013-03-01

    Full Text Available Wireless sensor networks (WSNs have become an active research area for the researchers due to their widely used range of application potential in areas such as target detection and tracking, environmental monitoring, industrial process monitoring, and tactical systems. Usually, after the deployment of sensor nodes in the hazardous, hostile or remote areas, these sensor nodes work on their own. These sensor nodes will have to work with their limited and none replenish able energy resources. Although energy conservation in communication can be performed in different layers of the TCP/IP protocol suit, energy conservation at MAC layer is found to be the most effective one due to its ability to control the radio directly. Therefore, to ensure a long-lived network of wireless communicating sensors, we are in need of a MAC protocol that is able to improve energy efficiency by maximizing sleep duration, minimizing idle listening and overhearing, and eliminating collision of packets. This paper presents a review of the most recent works regarding with MAC protocols for applications of wireless sensor networks. First we present discussions on radio energy model, energy consumption measuring and the sensor network properties that are crucial for the design of MAC layer protocols. Second we describe the several available energy-efficient MAC protocols for sensor networks emphasizing their energy saving methods. These energyefficient MAC protocols are mainly divided into two groups, i.e. synchronous and asynchronous MAC protocols. Finally, we discuss some future research issues in the design of MAC protocol for WSNs.

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

    Maria Sefuba

    2015-09-01

    Full Text Available 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.

  15. Adaptive-Reliable Medium Access Control Protocol for Wireless Body Area Networks

    Rahim, A.; Javaid, N.; M Aslam; Qasim, U.; Khan, Z. A.

    2012-01-01

    Extensive energy is consumed by Transceiver communication operation [1]. Existing research on MAC layer focuses to maximize battery-powered sensor node's life. Bottleneck of MAC layer protocol design for WBAN is to achieve high reliability and energy minimization. Majority of MAC protocols designed for WBANs are based upon TDMA approach. However, a new protocol needs to be defined to achieve high energy efficiency, fairness and avoid extra energy consumption due to synchronization.

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

    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.

  17. Energy-Efficient Medium Access Control Protocols for Wireless Sensor Networks

    Ren Qingchun

    2006-01-01

    Full Text Available A key challenge for wireless sensor networks is how to extend network lifetime with dynamic power management on energy-constraint sensor nodes. In this paper, we propose two energy-efficient MAC protocols: asynchronous MAC (A-MAC protocol and asynchronous schedule-based MAC (ASMAC protocol. A-MAC and ASMAC protocols are attractive due to their suitabilities for multihop networks and capabilities of removing accumulative clock-drifts without any network synchronization. Moreover, we build a traffic-strength- and network-density-based model to adjust essential algorithm parameters adaptively. Simulation results show that our algorithms can successfully acquire the optimum values of power-on/off duration, schedule-broadcast interval, as well as super-time-slot size and order. These algorithm parameters can ensure adequate successful transmission rate, short waiting time, and high energy utilization. Therefore, not only the performance of network is improved but also its lifetime is extended when A-MAC or ASMAC is used.

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

    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....

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

    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.

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

    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. PMID:20703634

  1. Anonymous Biometric Access Control

    Shuiming Ye

    2009-01-01

    Full Text Available Access control systems using the latest biometric technologies can offer a higher level of security than conventional password-based systems. Their widespread deployments, however, can severely undermine individuals' rights of privacy. Biometric signals are immutable and can be exploited to associate individuals' identities to sensitive personal records across disparate databases. In this paper, we propose the Anonymous Biometric Access Control (ABAC system to protect user anonymity. The ABAC system uses novel Homomorphic Encryption (HE based protocols to verify membership of a user without knowing his/her true identity. To make HE-based protocols scalable to large biometric databases, we propose the k-Anonymous Quantization (kAQ framework that provides an effective and secure tradeoff of privacy and complexity. kAQ limits server's knowledge of the user to k maximally dissimilar candidates in the database, where k controls the amount of complexity-privacy tradeoff. kAQ is realized by a constant-time table lookup to identity the k candidates followed by a HE-based matching protocol applied only on these candidates. The maximal dissimilarity protects privacy by destroying any similarity patterns among the returned candidates. Experimental results on iris biometrics demonstrate the validity of our framework and illustrate a practical implementation of an anonymous biometric system.

  2. Direct data access protocols benchmarking on DPM

    Furano, Fabrizio; Devresse, Adrien; Keeble, Oliver; Mancinelli, Valentina

    2015-12-01

    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 information about any data access protocol to the same monitoring infrastructure that is used to monitor the Xrootd deployments. Our goal is to evaluate under which circumstances the HTTP-based protocols can be good enough for batch or interactive data access. In this contribution we show and discuss the results that our test systems have collected under the circumstances that include ROOT analyses using TTreeCache and stress tests on the metadata performance.

  3. Direct data access protocols benchmarking on DPM

    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...

  4. Improving access to primary care for Aboriginal babies in Western Australia: study protocol for a randomized controlled trial

    McAullay, Daniel; McAuley, Kimberley; Marriott, Rhonda; Pearson, Glenn; Jacoby, Peter; Ferguson, Chantal; Geelhoed, Elizabeth; Coffin, Juli; Green, Charmaine; Sibosado, Selina; Henry, Barbara; Doherty, Dorota; Edmond, Karen

    2016-01-01

    Background Despite a decade of substantial investments in programs to improve access to primary care for Aboriginal mothers and infants, more than 50 % of Western Australian Aboriginal babies are still not receiving primary and preventative care in the early months of life. Western Australian hospitals now input birth data into the Western Australian electronic clinical management system within 48 hours of birth. However, difficulties have arisen in ensuring that the appropriate primary care ...

  5. Stream Control Transmission Protocol Steganography

    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.

  6. Android Access Control Extension

    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.

  7. 水声通信网络媒介访问控制协议的研究%Research on Media Access Control Protocol for Underwater Acoustic Communication Network

    匡锐

    2014-01-01

    Media access control protocol is the most important part of data link layer protocol, which plays a decisive significance to the distribution of channels. This paper designs a media access control protocol that com-bines normal access mode and MACAW access mode respectively modeling of channel and underwater communi-cation equipment, simulating the normal access mode and MACAW access mode in throughput, bit error rate and transmission delay.%媒介访问控制协议是数据链路层协议中最重要的部分,对信道的分配起着决定性的作用。本文设计了一种普通访问模式和MACAW访问模式相结合的媒介访问控制协议,分别对信道和水下通信设备进行建模,对普通访问模式和MACAW访问模式在吞吐量、误码率和传输延迟进行了仿真。

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

    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.

  9. Android Access Control Extension

    Anton Baláž; Branislav Madoš; Michal Ambróz

    2015-01-01

    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 pr...

  10. MAC Protocols for Optimal Information Retrieval Pattern in Sensor Networks with Mobile Access

    Yang Zhiyu

    2005-01-01

    Full Text Available In signal field reconstruction applications of sensor network, the locations where the measurements are retrieved from affect the reconstruction performance. In this paper, we consider the design of medium access control (MAC protocols in sensor networks with mobile access for the desirable information retrieval pattern to minimize the reconstruction distortion. Taking both performance and implementation complexity into consideration, besides the optimal centralized scheduler, we propose three decentralized MAC protocols, namely, decentralized scheduling through carrier sensing, Aloha scheduling, and adaptive Aloha scheduling. Design parameters for the proposed protocols are optimized. Finally, performance comparison among these protocols is provided via simulations.

  11. Power Control Protocols in VANET

    Samara, Ghassan; Salem, Amer O. Abu; Alhmiedat, Tareq

    2013-01-01

    Vehicular Ad hoc Networks (VANET) is one of the most challenging research area in the field of the Mobile Ad hoc Network (MANET), Power control is a critical issue in VANETwhere is should be managed carefully to help the channel to have high performance. In this paper a comparative study in the published protocols in the field of safety message dynamic power control will be presented and evaluated.

  12. Remote Memory Access Protocol Target Node Intellectual Property

    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.

  13. Media Access Control for Wireless Sensor and Actuator Networks

    Nabi, Muaz Un

    2012-01-01

    In a wireless network, the medium is a shared resource. The nodes in the network negotiate access of the shared resource using the Medium Access Control (MAC) protocol. The design of a MAC protocol for a sensor node is not the same as that for a wireless transceiver. Due to the transceiver characteristics, the MAC protocol design is limited in terms of medium access methods. However, in most cases, the protocols rely on simple access methods i.e. Time Division Multiple Access (TDMA) or Carrie...

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

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

    1999-01-01

    . 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......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...... (CBR), variable bit rate (VBR) and available bit rate (ABR) with different kinds of applications, such as voice, video-conferening, MPEG video and Web-browising, is considered to evaluate the proposed protocol. Simulation results show that the proposed multiple access protocol can support a wide range...

  15. A randomised controlled non-inferiority trial of primary care-based facilitated access to an alcohol reduction website (EFAR-FVG): the study protocol

    Struzzo, P.; Scafato, E.; McGregor, R.; Della Vedova, R.; Verbano, L.; Lygidakis, C.; Tersar, C.; Crapesi, L.; Tubaro, G.; Freemantle, N; Wallace, P.

    2013-01-01

    Introduction There is a strong body of evidence demonstrating the effectiveness of brief interventions by primary care professionals for risky drinkers. However, implementation levels remain low because of time constraints and other factors. Facilitated access to an alcohol reduction website offers primary care professionals a time-saving alternative to standard face-to-face intervention, but it is not known whether it is as effective. Methods and analysis A randomised controlled non-inferior...

  16. DCP, a distributed-control polling mac protocol

    Conti, Marco; Gregori, Enrico; Lenzini, Luciano

    1990-01-01

    This paper describes and analyzes a novel MAC protocol named Distributed-Control Polling (DCP), which has been designed to bring together the most interesting features of distributed-control MAC protocols (e.g., DQDB) and centralized token-passing MAC protocols (e.g. FASNET, FDDI, EXPRESS_NET). From the fully?distributed MAC protocols, DCP acquires the capability to guarantee both a complete utilization of the medium capacity and an access delay of only a few slots at light loads. From the ce...

  17. Advanced access control system

    A prototype voice verification system has been installed which provides the required positive identification at the main site access control point. This system compares an individual's file voice print with a sample voice print obtained from the individual when an attempt is made to enter the site. The voice system transmits the individual's identify to a central processor. The system installed at the Barnwell Nuclear Fuel Plant is described

  18. Analysing Access Control Specifications

    Probst, Christian W.; Hansen, René Rydhof

    2009-01-01

    common tool to answer this question, analysis of log files, faces the problem that the amount of logged data may be overwhelming. This problems gets even worse in the case of insider attacks, where the attacker’s actions usually will be logged as permissible, standard actions—if they are logged at all....... 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...

  19. Advanced access control system

    A prototype voice verification system has been installed which provides the required positive identification at the main site access control point. This system compares an individual's file voice print with a sample voice print obtained from the individual when an attempt is made to enter the site. The voice system transmits the individual's identity to a central processor. The central processor associates that individual's authorization file with a card-key obtained at the access point. The system generates a record of personnel movement, provides a personnel inventory on a real-time basis, and it can retrieve a record of all prior events. The system installed at the Barnwell Nuclear Fuel Plant is described

  20. Physical Access Control Database

    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...

  1. Protocol and networking design issues for local access WDM networks

    Salvador, Marcos Rogério; Heemstra de Groot, Sonia; Niemegeers, Ignas

    1999-01-01

    This report gives an overview of some of the protocol and networking design issues that have been addressed in Flamingo, a major ongoing project which investigates the use of WDM optical technology in local access networks. Quality of service delivery and wavelength assignment are focused on in this report. A brief introduction to optical networks and WDM as well as a brief description of Flamingo are also included in this report.

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

    Meybodi, Soroush Afkhami

    2012-01-01

    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...... accordance 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.......This dissertation reports the result of efforts to identify and solve the problems that arise when a control system is to be designed for various industrial case studies of the Plug and Play Process Control (P3C) project that require autonomous addition/removal of sensors, actuators and subsystems...

  3. 多预约信息转发的协作信道预约多址接入协议%A Multiple Access Control Protocol with Multiple Reservation Information Relay and Cooperative Channel Reservation

    袁韵洁; 李波

    2012-01-01

    针对Ad Hoc网络中实时业务在背景业务繁重时信道接入效率低的问题,提出一种邻节点协作转发信道预约信息(CRI)的多址接入协议(M-CCRM).节点在发送数据分组前,选取多条CRI作为其数据开销,在控制该开销不超过预先设定门限的基础上,将这些CRI随分组一起发送;收到数据分组的邻节点提取其携带的CRI,记录下那些自己位于其预约范围内的CRI,避免在这些CRI的预约时段内接入信道.M-CCRM协议扩大了CRI的覆盖范围,解决了由于信道衰落和(或)分组冲突导致的CRI丢失问题,提高了实时业务的信道接入效率.仿真结果表明,当开销门限为0.02时,M-CCRM协议的实时业务发送失败概率比基本信道预约协议和基本协作预约协议分别降低了31%和20%.%A new multiple access control (MAC) protocol called M-CCRM is proposed to solve the problem of poor channel access efficiency for real-time traffic in Ad Hoc networks with heavy background traffic loads. The proposed protocol bases on the idea of distributing channel reservation information (CRI) through cooperative relays of neighboring nodes. Before a node transmits a packet, multiple CRIs are carefully selected and piggy-backed with the packet so as to limit the corresponding overheads caused by carrying CRIs to be lower than a predefined threshold. By o-verhearing the packet, neighboring nodes record some of the CRIs as long as they are within the channel reservation distance of the CRIs, and then avoid to access the channel while the traffic indicated by the CRIs are carrying on. The proposed MAC protocol enlarges the coverage area of the announced CRIs, and avoids the possible missing of CRIs caused by channel fading and (or) packet collisions. Therefore, the channel access efficiency for real-time traffic is significantly increased. Simulations and comparisons with the basic channel reservation protocol and the basic cooperative channel reservation

  4. 基于语音时隙机制的车载自组网MAC协议%Media Access Control Protocol Based on Voice Time Slot Mechanism in VANET

    谢旭; 李丽华; 付伟

    2012-01-01

    在节点高速运动的车载组网多跳通信中,如何快速选择下一跳中继节点是目前无线自组网亟待解决的问题.为此,提出一种基于类语音时隙划分信道竞争机制的时分复用协议,采用类似语音优先权接入的语音突发方式解决多跳中继选择问题.仿真结果表明,在不同节点分布的运动场景下,使用语音突发方式的MAC协议较传统的时分复用随机接入方式具有更短的接入延时与更低的网络开销.%In Vehicle Ad Hoc Networks(VANET) multi-hop communication with nodes of high speed, a problem of how to choose a next hop relay rapidly makes a significant sense. In this paper, a slot assignment for voice access named black-burst scheme based Time Division Multiple Address(TDMA) is proposed for channel access contention. The problem of relay selection can be solved as a method of voice access control with priority. Simulation results show that in scenarios of movement with different nodes distribution, a shorter access delay and a lower cost can be obtained in MAC protocols based on black-burst mechanism compared with the traditional TDMA random channel access method.

  5. An architecture and protocol, an access control model, and a sighting blurring algorithm for improving users' security in the context of location based services operating over the internet

    Dunne, Cameron R.

    2009-01-01

    A new type of service, known as a Location Based Service (LBS), is emerging that incorporates users' location information, and many of these LBSs operate over the Internet. However, the potential misuse of this location information is a serious concern. Therefore, the main goal of this thesis is to develop techniques, which increase users' security and privacy, for use with these LBSs. The rst technique that we propose is a three-party protocol that is used to mutually ident...

  6. IVOA Recommendation: Simple Line Access Protocol Version 1.0

    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...

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

    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.

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

    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.

  9. Early intervention for depression and anxiety in 16-18-year-olds: Protocol for a feasibility cluster randomised controlled trial of open-access psychological workshops in schools (DISCOVER).

    Michelson, Daniel; Sclare, Irene; Stahl, Daniel; Morant, Nicola; Bonin, Eva-Maria; Brown, June S L

    2016-05-01

    Adolescence is a vulnerable period for the development of mental health problems. The DISCOVER intervention aims to provide accessible, acceptable and cost-effective psychological support for stressed adolescents in inner-city secondary schools. The intervention uses age-appropriate cognitive-behavioural therapy (CBT) methods and materials, delivered in an interactive 1-day workshop with additional telephone support. An open-access entry route allows students to self-refer. This protocol describes a feasibility cluster randomised controlled trial (RCT) comparing DISCOVER with a waitlist control condition. The study will run across 10 clusters (secondary schools) in the inner London Boroughs of Southwark and Lambeth. Participants are students aged over 16years who are seeking help with anxiety and/or depressive symptoms. Key feasibility parameters relate to the proportion of students willing to participate in the research following publicity events; the proportion of students who complete the intervention; and response rates for outcome measures. Outcome variance estimates and intra-cluster correlations will be obtained for future power calculations. Qualitative methods will be used to explore the acceptability of the intervention and research procedures for students and school staff. The feasibility of an economic evaluation will also be examined. The results will (i) determine the appropriateness of proceeding to a definitive full-scale trial; and (ii) inform the development of an optimised version of the DISCOVER intervention that can be tested within feasible parameters. PMID:26883283

  10. Controlled Delegation Protocol in Mobile RFID Networks

    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.

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

    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.

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

    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...

  13. RFID access control

    Luzar, Boštjan

    2012-01-01

    The goal of the thesis was to learn about the procedure of developing applications based on microcontrollers using the Arduino development platform and the IDE environment. Through practical development in the Arduino environment we realized a logic which is capable to authorize access to specific locations and areas based on 125 kHz RFID tags. Although many solutions exist, most of them require a lot of hardware and software because of their modular design and communication types, the so...

  14. IVOA Recommendation: Simple Spectral Access Protocol Version 1.1

    Tody, Doug; McDowell, Jonathan; Bonnarel, Francois; Budavari, Tamas; Busko, Ivo; Micol, Alberto; Osuna, Pedro; Salgado, Jesus; Skoda, Petr; Thompson, Randy; Valdes, Frank

    2012-01-01

    The Simple Spectral Access (SSA) Protocol (SSAP) defines a uniform interface to remotely discover and access one dimensional spectra. SSA is a member of an integrated family of data access interfaces altogether comprising the Data Access Layer (DAL) of the IVOA. SSA is based on a more general data model capable of describing most tabular spectrophotometric data, including time series and spectral energy distributions (SEDs) as well as 1-D spectra; however the scope of the SSA interface as specified in this document is limited to simple 1-D spectra, including simple aggregations of 1-D spectra. The form of the SSA interface is simple: clients first query the global resource registry to find services of interest and then issue a data discovery query to selected services to determine what relevant data is available from each service; the candidate datasets available are described uniformly in a VOTable format document which is returned in response to the query. Finally, the client may retrieve selected datasets ...

  15. A randomised controlled non-inferiority trial of primary care-based facilitated access to an alcohol reduction website (EFAR Spain): the study protocol

    Lopez-Pelayo, H.; Wallace, P.; Segura, L.; Miquel, L.; DIAZ, E; Teixido, L.; Baena, B.; Struzzo, P.; Palacio-Vieira, J.; Casajuana, C.; Colom, J; Gual, A.

    2014-01-01

    Introduction Early identification (EI) and brief interventions (BIs) for risky drinkers are effective tools in primary care. Lack of time in daily practice has been identified as one of the main barriers to implementation of BI. There is growing evidence that facilitated access by primary healthcare professionals (PHCPs) to a web-based BI can be a time-saving alternative to standard face-to-face BIs, but there is as yet no evidence about the effectiveness of this approach relative to conventi...

  16. 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.

    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.

  17. Diagrammatization of the Transmission Control Protocol

    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.

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

    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.

  19. Collision-free prioritized medium access control in wireless networks with hidden nodes

    Andersson, Björn; Pereira, Nuno; Tovar, Eduardo

    2006-01-01

    We propose a collision-free medium access control (MAC) protocol, which implements static-priority scheduling and works in the presence of hidden nodes. The MAC protocol allows multiple masters and is fully distributed; it is an adaptation to a wireless channel of the dominance protocol used in the CAN bus. But unlike that protocol, our protocol does not require a node having the ability to sense the channel while transmitting to the channel. Our protocol is collision-free even in...

  20. Analysis of a Priority Stack Random Access Protocol In W-CDMA Systems

    Al Agha, Khaldoun; Jacquet, Philippe; Vvedenskay, Nikita

    2000-01-01

    The stack protocol (called also tree protocol) can be used in order to introduce a priority mechanism on the random access stage in W-CDMA. Indeed, after second generation networks supporting voice service only, the third generation systems (UMTS) should offer more services with quality and priority. However, all priorities in the UMTS system are based on the dedicated channel and after the random access mechanism that use the weak access protocol: slotted aloha. In this paper, we analyze the...

  1. Efficient Controlled Quantum Secure Direct Communication Protocols

    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.

  2. Robust access control framework for mobile cloud computing network

    Li, F; Rahulamathavan, Y.; Conti, M.; Rajarajan, M.

    2015-01-01

    Unified communications has enabled seamless data sharing between multiple devices running on various platforms. Traditionally, organizations use local servers to store data and employees access the data using desktops with predefined security policies. In the era of unified communications, employees exploit the advantages of smart devices and 4G wireless technology to access the data from anywhere and anytime. Security protocols such as access control designed for traditional setup are not su...

  3. Adaptive MAC-layer protocol for multiservice digital access via tree and branch communication networks

    Sriram, Kotikalapudi; Li, Chia-Chang; Magill, Peter; Whitaker, Norman A.; Dail, James E.; Dajer, Miguel A.; Siller, Curtis A.

    1995-11-01

    Described here is an adaptive MAC-layer protocol that supports multiservice (STM and ATM) applications in the context of subscriber access to tree and branch (e.g., fiber-coaxial cable) networks. The protocol adapts to changing demands for a mix of circuit and cell mode applications, and efficiently allocates upstream and downstream bandwidth to a variety of bursty and isochronous traffic sources. In the case of a hybrid fiber-coaxial (HFC) network the protocol resides in customer premises equipment and a common head-end controller. A medium-access control (MAC) processor provides for dividing the time domain for a given digital bitstream into successive frames, each with multiple STM and ATM time slots. Within the STM region of a frame, variable length time slots are allocated to calls (e.g., telephony, video telephony) requiring different amounts of bandwidth. A contention access signaling channel is also provided in this region for call control and set-up requests. Within the ATM region fixed-length time slots accommodate one individual ATM cell. These ATM time slots may be reserved for a user for the duration of a call or burst of successive ATM cells, or shared via a contention process. At least one contention time slot is available for signaling messages related to ATM call control and set-up requests. Further, the fixed-length ATM time slots may be reserved by a user for the duration of a call, or shared through a contention process. This paper describes the MAC-layer protocol, its relation to circuit- and ATM- amenable applications, and its performance with respect to signaling throughput and latency, and bandwidth efficiency for several service scenarios.

  4. Operational protocols for controlling accelerator equipment

    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.)

  5. Operational protocols for controlling accelerator equipment

    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.).

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

    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. Comparison of High Speed Congestion Control Protocols

    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.

  8. Dynamic Characteristics of Explicit Control Protocol

    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.

  9. Towards Trusted Network Access Control

    Bente, Ingo; von Helden, Josef

    Network Access Control (NAC) solutions promise to significantly increase the security level of modern networks. In short, they allow to measure the integrity state of an endpoint that tries to get access to the network. Based upon the measurement results, which are compared to a defined NAC policy, access to the network can be allowed or denied. One problem of all currently available NAC solutions is referred to as the “lying endpoint” problem. Normally, special software components are responsible for gathering the relevant integrity information on the endpoint. If an attacker modifies those software components, an endpoint can lie about its current integrity state. Therefore, endpoints which are not compliant to the defined NAC policy can get access to the network. Those endpoints must be considered as potential threat. This paper summarizes a possible solution for the lying endpoint problem based upon the specifications of the Trusted Computing Group (TCG) and the results of the two research projects TNC@ FHH and Turaya. The goal is to develop an open source, TNC compatible NAC solution with full TPM support within a new research project: tNAC.

  10. Controlling Access to Suicide Means

    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.

  11. Access Request Trustworthiness in Weighted Access Control Framework

    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.

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

    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

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

    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

  14. Addressing Mobility in Wireless Sensor Media Access Protocol

    Huan Pham; Sanjay Jha

    2005-01-01

    Handling mobility in wireless sensor networks presents several new challenges. Techniques developed for other mobile networks, such as mobile phone or mobile adhoc networks can not be applicable, as in these networks energy is not a very critical resource. This paper presents a new adaptive Mobility-aware Sensor MAC protocol (MS-MAC) for mobile sensor applications. In MS-MAC protocol, a node detects its neighbor's mobility based on a change in its received signal level from the neighbor, or a...

  15. Does access to a colorectal cancer screening website and/or a nurse-managed telephone help line provided to patients by their family physician increase fecal occult blood test uptake?: A pragmatic cluster randomized controlled trial study protocol

    Clouston Kathleen

    2012-05-01

    Full Text Available Abstract Background Fecal occult blood test screening in Canada is sub-optimal. Family physicians play a central role in screening and are limited by the time constraints of clinical practice. Patients face multiple barriers that further reduce completion rates. Tools that support family physicians in providing their patients with colorectal cancer information and that support uptake may prove useful. The primary objective of the study is to evaluate the efficacy of a patient decision aid (nurse-managed telephone support line and/or colorectal cancer screening website distributed by community-based family physicians, in improving colorectal cancer screening rates. Secondary objectives include evaluation of (disincentives to patient FOBT uptake and internet use among 50 to 74 year old males and females for health-related questions. Challenges faced by family physicians in engaging in collaborative partnerships with primary healthcare researchers will be documented. Methods/design A pragmatic, two-arm, randomized cluster controlled trial conducted in 22 community-based family practice clinics (36 clusters with 76 fee-for-service family physicians in Winnipeg, Manitoba, Canada. Each physician will enroll 30 patients attending their periodic health examination and at average risk for colorectal cancer. All physicians will follow their standard clinical practice for screening. Intervention group physicians will provide a fridge magnet to each patient that contains information facilitating access to the study-specific colorectal cancer screening decision aids (telephone help-line and website. The primary endpoint is patient fecal occult blood test completion rate after four months (intention to treat model. Multi-level analysis will include clinic, physician and patient level variables. Patient Personal Health Identification Numbers will be collected from those providing consent to facilitate analysis of repeat screening behavior. Secondary outcome

  16. Optical Shared Memory Computing and Multiple Access Protocols for Photonic Networks

    Li, Kuang-Yu.

    In this research we investigate potential applications of optics in massively parallel computer systems, especially focusing on design issues in three-dimensional optical data storage and free-space photonic networks. An optical implementation of a shared memory uses a single photorefractive crystal and can realize the set of memory modules in a digital shared memory computer. A complete instruction set consists of R sc EAD, W sc RITE, S sc ELECTIVE E sc RASE, and R sc EFRESH, which can be applied to any memory module independent of (and in parallel with) instructions to the other memory modules. In addition, a memory module can execute a sequence of R sc EAD operations simultaneously with the execution of a W sc RITE operation to accommodate differences in optical recording and readout times common to optical volume storage media. An experimental shared memory system is demonstrated and its projected performance is analyzed. A multiplexing technique is presented to significantly reduce both grating- and beam-degeneracy crosstalk in volume holographic systems, by incorporating space, angle, and wavelength as the multiplexing parameters. In this approach, each hologram, which results from the interference between a single input node and an object array, partially overlaps with the other holograms in its neighborhood. This technique can offer improved interconnection density, optical throughput, signal fidelity, and space-bandwidth product utilization. Design principles and numerical simulation results are presented. A free-space photonic cellular hypercube parallel computer, with emphasis on the design of a collisionless multiple access protocol, is presented. This design incorporates wavelength-, space-, and time-multiplexing to achieve multiple access, wavelength reuse, dense connectivity, collisionless communications, and a simple control mechanism. Analytic models based on semi-Markov processes are employed to analyze this protocol. The performance of the

  17. A Linux Implementation of Temporal Access Controls

    Chiang, Ken; Nguyen, Thuy D.; Irvine, Cynthia E.

    2007-01-01

    Control of access to information based upon temporal attributes can add another dimension to access control. To demonstrate the feasibility of operating system level support for temporal access controls, the Time Interval File Protection System (TIFPS), a prototype of the Time Interval Access Control (TIAC) model, has been implemented by modifying Linux extended attributes to include temporal metadata associated both with files and users. The Linux Security Module was used to provide hooks fo...

  18. Exploiting Combination Techniques in Random Access MAC Protocols: Enhanced Contention Resolution ALOHA

    Clazzer, Federico; Kissling, Christian; Marchese, Mario

    2016-01-01

    Recently, random access (RA) protocols have acquired new interest from the scientific community not only in satellite communication scenarios but also due to the opening of new fields as smart grid and machine-to-machine (M2M) applications. Unslotted ALOHA-like RA protocols are very attractive for such applications thanks to the low complexity transmitters and to their complete avoidance of synchronization requirements. Evolutions of the ALOHA protocol employ time diversity through proactive ...

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

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

    1999-01-01

    In this paper, we propose a knowledge-based multiple access protocol for the extension of wireline ATM to wireless networks. The objective is to enable effecient transmission of all kinds of ATM traffic in the wireless channel with guaranteed QoS.The proposed protocol utilixes knowledge of the main...... guaranteed QoS requirements to a variety of ATM applications....

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

    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.

  1. An Access Control Framework for Reflective Middleware

    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.

  2. Performance Analysis of WBAN MAC Protocol under Different Access Periods

    Pervez Khan; Niamat Ullah; Md. Nasre Alam; Kyung Sup Kwak

    2015-01-01

    The IEEE 802.15.6 is a new standard on wireless body area network (WBAN) for short-range, extremely low power wireless communication with high data rates in the vicinity of, or inside, a human body. The standard defines two contention-based channel access schemes: slotted ALOHA and carrier sense multiple access with collision avoidance (CSMA/CA) using an alternative binary exponential backoff procedure. The standard supports quality of service (QoS) differentiation through user priorities and...

  3. MANAGEMENT AND CONTROL OF FACULTY INFRASTRUCTURE USING SNMP PROTOCOL

    Saje, Tadeja

    2013-01-01

    Thesis presents a system to monitor and control computer systems and other devices. The system uses SNMP protocol. It permits better analyze, control and resolution of failures in operation of our systems. SNMP protocol is communication layer between controller and controlled device. Presented will be theoretical basis and security issues of SNMP. Practical part will be implementation of simple control system.

  4. Random Access Game and Medium Access Control Design

    Chen, Lijun; Low, Steven H.; Doyle, John C.

    2010-01-01

    Motivated partially by a control-theoretic viewpoint, we propose a game-theoretic model, called random access game, for contention control. We characterize Nash equilibria of random access games, study their dynamics, and propose distributed algorithms (strategy evolutions) to achieve Nash equilibria. This provides a general analytical framework that is capable of modeling a large class of system-wide quality-of-service (QoS) models via the specification of per-node util...

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

    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.

  6. Role Based Access Control system in the ATLAS experiment

    The complexity of the ATLAS experiment motivated the deployment of an integrated Access Control System in order to guarantee safe and optimal access for a large number of users to the various software and hardware resources. Such an integrated system was foreseen since the design of the infrastructure and is now central to the operations model. In order to cope with the ever growing needs of restricting access to all resources used within the experiment, the Roles Based Access Control (RBAC) previously developed has been extended and improved. The paper starts with a short presentation of the RBAC design, implementation and the changes made to the system to allow the management and usage of roles to control access to the vast and diverse set of resources. The RBAC implementation uses a directory service based on Lightweight Directory Access Protocol to store the users (∼3000), roles (∼320), groups (∼80) and access policies. The information is kept in sync with various other databases and directory services: human resources, central CERN IT, CERN Active Directory and the Access Control Database used by DCS. The paper concludes with a detailed description of the integration across all areas of the system.

  7. Role Based Access Control system in the ATLAS experiment

    Valsan, M. L.; Dobson, M.; Lehmann Miotto, G.; Scannicchio, D. A.; Schlenker, S.; Filimonov, V.; Khomoutnikov, V.; Dumitru, I.; Zaytsev, A. S.; Korol, A. A.; Bogdantchikov, A.; Avolio, G.; Caramarcu, C.; Ballestrero, S.; Darlea, G. L.; Twomey, M.; Bujor, F.

    2011-12-01

    The complexity of the ATLAS experiment motivated the deployment of an integrated Access Control System in order to guarantee safe and optimal access for a large number of users to the various software and hardware resources. Such an integrated system was foreseen since the design of the infrastructure and is now central to the operations model. In order to cope with the ever growing needs of restricting access to all resources used within the experiment, the Roles Based Access Control (RBAC) previously developed has been extended and improved. The paper starts with a short presentation of the RBAC design, implementation and the changes made to the system to allow the management and usage of roles to control access to the vast and diverse set of resources. The RBAC implementation uses a directory service based on Lightweight Directory Access Protocol to store the users (~3000), roles (~320), groups (~80) and access policies. The information is kept in sync with various other databases and directory services: human resources, central CERN IT, CERN Active Directory and the Access Control Database used by DCS. The paper concludes with a detailed description of the integration across all areas of the system.

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

    V.Nivedhitha; B.Baranidharan; B. Santhi

    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.

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

    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.

  10. An electronically controlled automatic security access gate

    Jonathan A. Enokela; Michael N. TYOWUAH

    2014-01-01

    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 ...

  11. Efficient Access Control for Wireless Sensor Data

    Sorniotti, Alessandro; Molva, Refik; GOMEZ, Laurent; Trefois, Christophe; Laube, Annett; Scaglioso, Piervito

    2009-01-01

    Abstract Although very developed in many sectors (databases, filesystems), access control schemes are still somewhat elusive when it comes to wireless sensor net- works. However, it is clear that many WSN systems—such as healthcare and automotive ones—need a controlled access to data that sensor nodes produce, given its high sensitivity. Enforcing access control in wireless sensor networks is a particularly difficult task due to the limited computational capacity of wireless sensor nodes. In ...

  12. Evaluation of file access control implementations

    Madar, Fatima Ali

    2005-01-01

    This thesis discusses two implementations of file access controls: the UNIX Permissions (UP) and the Access Control List (ACL). We will evaluate advantages and weaknesses in these two implementations. The criteria of evaluation are usefulness, security and manageability. The level of usefulness of systems was measured by evaluating user-surveys. The level of security was measured by comparing the implementations against well-established file access control models concerning privacy, inte...

  13. Access control system for ISABELLE

    An access system based on the one now in operation at the CERN ISR is recommended. Access doors would presumably be located at the entrances to the utility tunnels connecting the support buildings with the ring. Persons requesting access would insert an identity card into a scanner to activate the system. The request would be autologged, the keybank adjacent to the door would be unlocked and ISABELLE operations would be notified. The operator would then select the door, activating a TV-audio link. The person requesting entry would draw a key from the bank, show it and his film badge to the operator who would enable the door release

  14. An Efficient Secure Real-Time Concurrency Control Protocol

    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.

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

    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...... three key properties of EH-WSNs: adaptability of energy consumption, distributed energy-aware load balancing and support for different application-specific requirements....

  16. Improving Network Performances by Integrating Erasure Coding and Game Theory Techniques in Random Access Protocols

    Mohamed Lamine Boucenna

    2013-09-01

    Full Text Available This research focuses on network performance and how to solve the problem of low throughput in the Aloha Medium Access Control (MAC protocol and its derivatives. For this purpose, we propose two complementary solutions. The first consists of the integration of the erasure coding scheme in this protocol to recover collided packets and to reduce the rate of collision between transmitted packets. Here, since each node sends N coded packets instead of the k original packets, we have (N-k redundant packets. The introduction of redundancy and subsequently structuring it in an exploitable manner, allows serious errors injected by the channel to be corrected. However, if each node attempts to achieve its best output without regard for the other nodes’ actions, this could affect overall system throughput. To analyze such conflicting situations where the action of one node has an impact on the other nodes’ actions, we add a complementary solution, which is based on the game theory technique of acquiring network equilibrium. This makes the network stronger and able to resist many collisions.

  17. Access control and service-oriented architectures

    Leune, C.J.

    2007-01-01

    Access Control and Service-Oriented Architectures" investigates in which way logical access control can be achieved effectively, in particular in highly dynamic environments such as service-oriented architectures (SOA's). The author combines state-of-the-art best-practice and projects these onto the

  18. 47 CFR 95.645 - Control accessibility.

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Control accessibility. 95.645 Section 95.645 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PERSONAL RADIO SERVICES Technical Regulations Certification Requirements § 95.645 Control accessibility. (a) No...

  19. Proximity Displays for Access Control

    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…

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

    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.

  1. Design and Realization of An Access Controling System Based on 802 .1x Protocol%基于802.1x 协议的接入控制系统设计与实现磁

    刘福强; 李威; 李镞

    2014-01-01

    The technology of ethernet-port authentication and access controling based on 802 .1x protocal has many ad-vantages ,such as high efficiency ,is designed and built ,flexible application and easy operation .In this paper ,access-contro-ling system based on 802 .1x protocal is designed and built ,the key technical problems are researched ,such as the security mode of EAP-TLS and the efficiency of USBKEY authentication .%基于802.1x 协议的以太网端口认证与接入控制技术具有简洁高效、容易实现、应用灵活以及易于运营等诸多特点和优点。文章通过对802.1x 等相关协议的研究与分析,设计并实现了基于该协议的安全接入控制系统,并对基于EAP-TLS 的安全认证方式、基于 USBKEY 认证方式效率等关键问题进行了深入分析。

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

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

    2012-01-01

    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...... 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...

  3. Disk access controller for Multi 8 computer

    After having presented the initial characteristics and weaknesses of the software provided for the control of a memory disk coupled with a Multi 8 computer, the author reports the development and improvement of this controller software. He presents the different constitutive parts of the computer and the operation of the disk coupling and of the direct access to memory. He reports the development of the disk access controller: software organisation, loader, subprograms and statements

  4. Modelling Access Control For Healthcare Information Systems

    Ferreira, Ana; Chadwick, David W; Antunes, Luis

    2007-01-01

    The widening use of Information Systems, which allow the collection, extraction, storage, management and search of information, is increasing the need for information security. After a user is successfully identified and authenticated to a system, he needs to be authorised to access the resources he/she requested. Access control is part of this last process that checks if a user can access those resources. This is particularly important in the healthcare environment where there is the need to...

  5. Adaptive Code Division Multiple Access Protocol for Wireless Network-on-Chip Architectures

    Vijayakumaran, Vineeth

    Massive levels of integration following Moore's Law ushered in a paradigm shift in the way on-chip interconnections were designed. With higher and higher number of cores on the same die traditional bus based interconnections are no longer a scalable communication infrastructure. On-chip networks were proposed enabled a scalable plug-and-play mechanism for interconnecting hundreds of cores on the same chip. Wired interconnects between the cores in a traditional Network-on-Chip (NoC) system, becomes a bottleneck with increase in the number of cores thereby increasing the latency and energy to transmit signals over them. Hence, there has been many alternative emerging interconnect technologies proposed, namely, 3D, photonic and multi-band RF interconnects. Although they provide better connectivity, higher speed and higher bandwidth compared to wired interconnects; they also face challenges with heat dissipation and manufacturing difficulties. On-chip wireless interconnects is one other alternative proposed which doesn't need physical interconnection layout as data travels over the wireless medium. They are integrated into a hybrid NOC architecture consisting of both wired and wireless links, which provides higher bandwidth, lower latency, lesser area overhead and reduced energy dissipation in communication. However, as the bandwidth of the wireless channels is limited, an efficient media access control (MAC) scheme is required to enhance the utilization of the available bandwidth. This thesis proposes using a multiple access mechanism such as Code Division Multiple Access (CDMA) to enable multiple transmitter-receiver pairs to send data over the wireless channel simultaneously. It will be shown that such a hybrid wireless NoC with an efficient CDMA based MAC protocol can significantly increase the performance of the system while lowering the energy dissipation in data transfer. In this work it is shown that the wireless NoC with the proposed CDMA based MAC protocol

  6. Formal verification of safety protocol in train control system

    Zhang, Yan; TANG, TAO; Li, Keping; Mera Sanchez de Pedro, Jose Manuel; Zhu, Li; Zhao, Lin; Xu, Tianhua

    2011-01-01

    In order to satisfy the safety-critical requirements, the train control system (TCS) often employs a layered safety communication protocol to provide reliable services. However, both description and verification of the safety protocols may be formidable due to the system complexity. In this paper, interface automata (IA) are used to describe the safety service interface behaviors of safety communication protocol. A formal verification method is proposed to describe the safety communication pr...

  7. Access control and personal identification systems

    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

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

    Saad Meshhen Hardan

    2013-01-01

    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. ...

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

    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

  10. Campus Access Control System RFID Based

    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.

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

    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 for the...

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

    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

  13. A Low-Complexity Source Encoding Assisted Multiple Access Protocol for Voice/Data Integrated Networks

    Nariman Farvardin

    2005-02-01

    Full Text Available We present and evaluate the performance of a reduced complexity variation to the source encoding assisted multiple access (SEAMA protocol for integrating voice and data over a wireless network. This protocol, denoted as slow movable-boundary SEAMA (SMB-SEAMA, uses the same embedded and multistate voice encoder used in the original SEAMA protocol. However, in SMB-SEAMA, the movable voice/data boundary is not set based on the frame-by-frame bandwidth demand of the voice subsystem, but on the number of ongoing voice calls and the acceptable average distortion level. This results in a protocol that, at the network layer, is packet switched for both voice and data; however, from the data traffic point of view, voice looks like circuit switched. Analytical results show that SMB-SEAMA is a very efficient MAC protocol and present a model for analyzing the performance of queuing systems with a variable number of servers, each with constant service time. Consequently, while reducing the refreshing rate of the movable boundary by three orders of magnitude, simulation results demonstrate that SMB-SEAMA does not significantly degrade the system performance (less than 8% reduction in throughput and it still performs better than packet reservation multiple access (PRMA, the other known packet-switched scheme, which updates the boundary during every transmit frame.

  14. Access control issues in social networks

    Carreras Coch, Anna; Rodríguez Luna, Eva; Delgado Mercè, Jaime; Maroñas Borras, Xavier

    2010-01-01

    Social Networks, as the main axis of Web 2.0, are creating a number of interesting challenges to the research and standardisation communities. In this paper, we analyse the current and future use of access control policies in Social Networks. Subsequently, two main issues are addressed: the interoperability amongst systems using different policy languages and the lack of elements in the existing policy languages when trying to express Social Networks’ access control. In part...

  15. Quality control protocols for radiodiagnosis agents and radiopharmaceuticals

    Based on the compilation of pharmacopoeia methods, literature, manuals and other information developed in our laboratory, protocols have been prepared to carry out quality controls for radiodiagnosis agents (RDA), better known as kits and RDA labelled with Tc99m. Quality control protocols cover physicochemical and biological controls. Physicochemical controls described for RDA include physical characteristics, particle size and number, pH, chemical identification, humidity, tin II; whereas biological controls include sterility, acute toxicity and bacterial endotoxin determination (LAL). Physicochemical controls described for radiopharmaceuticals labelled with Tc99m are pH and radiochemical purity; while biological distribution is described as a biological control

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

    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.

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

    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

    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.))

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

    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.

  20. Access Control with RFID in the Internet of Things

    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......Future Internet research is needed to bring the Internet and the Things closer to each other to form the Internet of Things. As objects in our daily life gradually become smarter, there is an increasing benefit of networking these objects. In this article, a method to couple objects, the Things...... 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....

  1. Workflow Management in Occupational Medicine Using the Simple Workflow Access Protocol (SWAP)

    McClay, James

    2001-01-01

    There are over nine million reported work related injuries a year administered through the workers compensation system. Workers compensation requires extensive communication with employers and payers. Workflow automation tools exist in segments of the industry but there isn't a common communication system. The Internet Engineering Task Force (IETF) Working Group on Simple Workflow Access Protocol (SWAP) is addressing the specifications for workflow across the Internet. We are adapting these p...

  2. A High-Throughput Random Access Protocol for Multiuser MIMO Systems

    Yan Zhang

    2008-05-01

    Full Text Available We propose a high-throughput random access protocol for 2×2 multiuser multiple-input multiple-output (MIMO systems. The cross-layer mechanism utilizes the packets combining technique to exploit the advantages of both spatial multiplexing and multipacket reception. Analytical result indicates that the proposed scheme achieves 0.669 per spatial degree of freedom in stable throughput, which is much higher than those in the existed studies.

  3. Access Control Management for SCADA Systems

    Hong, Seng-Phil; Ahn, Gail-Joon; Xu, Wenjuan

    The information technology revolution has transformed all aspects of our society including critical infrastructures and led a significant shift from their old and disparate business models based on proprietary and legacy environments to more open and consolidated ones. Supervisory Control and Data Acquisition (SCADA) systems have been widely used not only for industrial processes but also for some experimental facilities. Due to the nature of open environments, managing SCADA systems should meet various security requirements since system administrators need to deal with a large number of entities and functions involved in critical infrastructures. In this paper, we identify necessary access control requirements in SCADA systems and articulate access control policies for the simulated SCADA systems. We also attempt to analyze and realize those requirements and policies in the context of role-based access control that is suitable for simplifying administrative tasks in large scale enterprises.

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

    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...

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

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

    2000-01-01

    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 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...

  6. A Calculus for Control Flow Analysis of Security Protocols

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

    2004-01-01

    The design of a process calculus for anaysing security protocols is governed by three factors: how to express the security protocol in a precise and faithful manner, how to accommodate the variety of attack scenarios, and how to utilise the strengths (and limit the weaknesses) of the underlying...... 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 of...... attack scenarios, that gives a more flexible format for expressing protocols, and that at the same time allows to circumvent some of the ``false positives'' arising in previous work....

  7. An Access Definition and Query Language : Towards a Unified Access Control Model

    Sonnenbichler, Andreas

    2013-01-01

    In this work we suggest a meta access control model emulating established access control models by configuration and offering enhanced features like the delegation of rights, ego-centered roles, and decentralized administration. The suggested meta access control model is named \\'\\'Access Definition and Query Language\\'\\' (ADQL). ADQL is represented by a formal, context-free grammar allowing to express the targeted access control model, policies, facts, and access queries as a formal language.

  8. Performance estimates for personnel access control systems

    Current performance estimates for personnel access control systems use estimates of Type I and Type II verification errors. A system performance equation which addresses normal operation, the insider, and outside adversary attack is developed. Examination of this equation reveals the inadequacy of classical Type I and II error evaluations which require detailed knowledge of the adversary threat scenario for each specific installation. Consequently, new performance measures which are consistent with the performance equation and independent of the threat are developed as an aid in selecting personnel access control systems

  9. Performance estimates for personnel access control systems

    Bradley, R. G.

    1980-10-01

    Current performance estimates for personnel access control systems use estimates of Type I and Type II verification errors. A system performance equation which addresses normal operation, the insider, and outside adversary attack is developed. Examination of this equation reveals the inadequacy of classical Type I and II error evaluations which require detailed knowledge of the adversary threat scenario for each specific installation. Consequently, new performance measures which are consistent with the performance equation and independent of the threat are developed as an aid in selecting personnel access control systems.

  10. Access Control in Data Management Systems

    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,

  11. Coded Splitting Tree Protocols

    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...... 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....

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

    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.

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

    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

  14. An electronically controlled automatic security access gate

    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.

  15. Network Access Control List Situation Awareness

    Reifers, Andrew

    2010-01-01

    Network security is a large and complex problem being addressed by multiple communities. Nevertheless, current theories in networking security appear to overestimate network administrators' ability to understand network access control lists (NACLs), providing few context specific user analyses. Consequently, the current research generally seems to…

  16. A Voting Protocol Based on the Controlled Quantum Operation Teleportation

    Tian, Juan-Hong; Zhang, Jian-Zhong; Li, Yan-Ping

    2016-05-01

    Based on the controlled quantum operation teleportation, a secure voting protocol is proposed in this paper. Genuine four-qubit entangled state functions as the quantum channel. The eligible voter's quantum operation which represents his vote information can be transmitted to the tallyman Bob with the help of the scrutineer Charlie. Voter's quantum identity authentication provides the anonymity of voters'ID, which is ensured by a zero-knowledge proof of the notary organization CA. Charlie's supervision in the whole voting process can make the protocol satisfy verifiability and non-reusability so as to avoid Bob's dishonest behaviour. The security analysis shows that the voting protocol satisfies unforgeability, and has great advantages over some relevant researches. Additionally, the quantum operation can be transmitted successfully with the probability 1, which can make the protocol reliable and practical.

  17. Survey of Performance based Transmission Control Protocol in MANET

    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.

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

    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.

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

    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.

  20. LANSCE personnel access control system (PACS)

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. The Personnel Access Control System (PACS) is a component of the RSS that is designed to prevent personnel access to areas where prompt radiation is a hazard. PACS was designed to replace several older personnel safety systems (PSS) with a single modem unified design. Lessons learned from the operation over the last 20 years were incorporated into a redundant sensor, single-point failure safe, fault tolerant, and tamper-resistant system that prevents access to the beam areas by controlling the access keys and beam stoppers. PACS uses a layered philosophy to the physical and electronic design. The most critical assemblies are battery backed up, relay logic circuits; less critical devices use Programmable Logic Controllers (PLCs) for timing functions and communications. Outside reviewers have reviewed the operational safety of the design. The design philosophy, lessons learned, hardware design, software design, operation, and limitations of the device are described

  1. VHDL IMPLEMENTATION OF TEST ACCESS PORT CONTROLLER

    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.

  2. Pace: Privacy-Protection for Access Control Enforcement in P2P Networks

    Sánchez-Artigas, Marc; García-López, Pedro

    In open environments such as peer-to-peer (P2P) systems, the decision to collaborate with multiple users — e.g., by granting access to a resource — is hard to achieve in practice due to extreme decentralization and the lack of trusted third parties. The literature contains a plethora of applications in which a scalable solution for distributed access control is crucial. This fact motivates us to propose a protocol to enforce access control, applicable to networks consisting entirely of untrusted nodes. The main feature of our protocol is that it protects both sensitive permissions and sensitive policies, and does not rely on any centralized authority. We analyze the efficiency (computational effort and communication overhead) as well as the security of our protocol.

  3. Proposed quality control protocol of a dual energy bone densitometer from Spanish protocol for quality control of radiology

    In this paper we propose additional testing to complete the tests by the Spanish Protocol for Quality Control of Diagnostic Radiology, taking into account the particular characteristics of these units, and including these tests in the estimation of patient dose dose assessment area. There is also the possibility to independently verify the quality control tests that are done automatically.

  4. Standard protocol stack for mission control

    Hooke, Adrian J.

    1994-01-01

    It is proposed to create a fully 'open' architectural specification for standardized space mission command and control. By being open, i.e., independent for any particular implementation, diversity and competition will be encouraged among future commercial suppliers of space equipment and systems. Customers of the new standard capability are expected to include: (1) the civil space community (e.g., NASA, NOAA, international Agencies); (2) the military space community (e.g., Air Force, Navy, intelligence); and (3) the emerging commercial space community (e.g., mobile satellite service providers).

  5. Speed control system for an access gate

    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.

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

    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.

  7. Scalable Video Streaming for Single-Hop Wireless Networks Using a Contention-Based Access MAC Protocol

    Monchai Lertsutthiwong

    2008-07-01

    Full Text Available Limited bandwidth and high packet loss rate pose a serious challenge for video streaming applications over wireless networks. Even when packet loss is not present, the bandwidth fluctuation, as a result of an arbitrary number of active flows in an IEEE 802.11 network, can significantly degrade the video quality. This paper aims to enhance the quality of video streaming applications in wireless home networks via a joint optimization of video layer-allocation technique, admission control algorithm, and medium access control (MAC protocol. Using an Aloha-like MAC protocol, we propose a novel admission control framework, which can be viewed as an optimization problem that maximizes the average quality of admitted videos, given a specified minimum video quality for each flow. We present some hardness results for the optimization problem under various conditions and propose some heuristic algorithms for finding a good solution. In particular, we show that a simple greedy layer-allocation algorithm can perform reasonably well, although it is typically not optimal. Consequently, we present a more expensive heuristic algorithm that guarantees to approximate the optimal solution within a constant factor. Simulation results demonstrate that our proposed framework can improve the video quality up to 26% as compared to those of the existing approaches.

  8. Establishing mandatory access control on Android OS

    Bugiel, Sven

    2015-01-01

    Common characteristic of all mobile operating systems for smart devices is an extensive middleware that provides a feature-rich API for the onboard sensors and user’s data (e.g., contacts). To effectively protect the device’s integrity, the user’s privacy, and to ensure non-interference between mutually distrusting apps, it is imperative that the middleware enforces rigid security and privacy policies. This thesis presents a line of work that integrates mandatory access control (MAC) mecha...

  9. Predictive access control for distributed computation

    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....

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

    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.

  11. Adaptive Congestion Control Protocol (ACCP for Wireless Sensor Networks

    James DzisiGadze

    2013-10-01

    Full Text Available In Wireless Sensor Networks (WSN when an event is detected there is an increase in data traffic that mightlead to packets being transmitted through the network close to the packet handling capacity of the WSN.The WSN experiences a decrease in network performance due to packet loss, long delays, and reduction inthroughput. In this paper we developed an adaptive congestion control algorithm that monitors networkutilization and adjust traffic levels and/or increases network resources to improve throughput and conserveenergy. The traffic congestion control protocol DelStatic is developed by introducing backpressuremechanism into NOAH. We analyzed various routing protocols and established that DSR has a higherresource congestion control capability. The proposed protocol, ACCP uses a sink switching algorithm totrigger DelStatic or DSR feedback to a congested node based on its Node Rank. From the simulationresults, ACCP protocol does not only improve throughput but also conserves energy which is critical tosensor application survivability on the field. Our Adaptive Congestion control achieved reliability, highthroughput and energy efficiency.

  12. Controlled breathing protocols probe human autonomic cardiovascular rhythms

    Cooke, W. H.; Cox, J. F.; Diedrich, A. M.; Taylor, J. A.; Beightol, L. A.; Ames, J. E. 4th; Hoag, J. B.; Seidel, H.; Eckberg, D. L.

    1998-01-01

    The purpose of this study was to determine how breathing protocols requiring varying degrees of control affect cardiovascular dynamics. We measured inspiratory volume, end-tidal CO2, R-R interval, and arterial pressure spectral power in 10 volunteers who followed the following 5 breathing protocols: 1) uncontrolled breathing for 5 min; 2) stepwise frequency breathing (at 0.3, 0.25, 0.2, 0.15, 0.1, and 0.05 Hz for 2 min each); 3) stepwise frequency breathing as above, but with prescribed tidal volumes; 4) random-frequency breathing (approximately 0.5-0.05 Hz) for 6 min; and 5) fixed-frequency breathing (0.25 Hz) for 5 min. During stepwise breathing, R-R interval and arterial pressure spectral power increased as breathing frequency decreased. Control of inspired volume reduced R-R interval spectral power during 0.1 Hz breathing (P respiration and R-R intervals and systolic pressure and R-R intervals. Random- and fixed-frequency breathing reduced end-tidal CO2 modestly (P tidal volume control attenuates low-frequency R-R interval oscillations and that fixed- and random-rate breathing may decrease CO2 chemoreceptor stimulation. We conclude that autonomic rhythms measured during different breathing protocols have much in common but that a stepwise protocol without stringent control of inspired volume may allow for the most efficient assessment of short-term respiratory-mediated autonomic oscillations.

  13. Control room envelope unfiltered air inleakage test protocols

    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.

  14. External access to ALICE controls conditions data

    ALICE Controls data produced by commercial SCADA system WINCCOA is stored in ORACLE database on the private experiment network. The SCADA system allows for basic access and processing of the historical data. More advanced analysis requires tools like ROOT and needs therefore a separate access method to the archives. The present scenario expects that detector experts create simple WINCCOA scripts, which retrieves and stores data in a form usable for further studies. This relatively simple procedure generates a lot of administrative overhead – users have to request the data, experts needed to run the script, the results have to be exported outside of the experiment network. The new mechanism profits from database replica, which is running on the CERN campus network. Access to this database is not restricted and there is no risk of generating a heavy load affecting the operation of the experiment. The developed tools presented in this paper allow for access to this data. The users can use web-based tools to generate the requests, consisting of the data identifiers and period of time of interest. The administrators maintain full control over the data – an authorization and authentication mechanism helps to assign privileges to selected users and restrict access to certain groups of data. Advanced caching mechanism allows the user to profit from the presence of already processed data sets. This feature significantly reduces the time required for debugging as the retrieval of raw data can last tens of minutes. A highly configurable client allows for information retrieval bypassing the interactive interface. This method is for example used by ALICE Offline to extract operational conditions after a run is completed. Last but not least, the software can be easily adopted to any underlying database structure and is therefore not limited to WINCCOA.

  15. External access to ALICE controls conditions data

    Jadlovský, J.; Jadlovská, A.; Sarnovský, J.; Jajčišin, Š.; Čopík, M.; Jadlovská, S.; Papcun, P.; Bielek, R.; Čerkala, J.; Kopčík, M.; Chochula, P.; Augustinus, A.

    2014-06-01

    ALICE Controls data produced by commercial SCADA system WINCCOA is stored in ORACLE database on the private experiment network. The SCADA system allows for basic access and processing of the historical data. More advanced analysis requires tools like ROOT and needs therefore a separate access method to the archives. The present scenario expects that detector experts create simple WINCCOA scripts, which retrieves and stores data in a form usable for further studies. This relatively simple procedure generates a lot of administrative overhead - users have to request the data, experts needed to run the script, the results have to be exported outside of the experiment network. The new mechanism profits from database replica, which is running on the CERN campus network. Access to this database is not restricted and there is no risk of generating a heavy load affecting the operation of the experiment. The developed tools presented in this paper allow for access to this data. The users can use web-based tools to generate the requests, consisting of the data identifiers and period of time of interest. The administrators maintain full control over the data - an authorization and authentication mechanism helps to assign privileges to selected users and restrict access to certain groups of data. Advanced caching mechanism allows the user to profit from the presence of already processed data sets. This feature significantly reduces the time required for debugging as the retrieval of raw data can last tens of minutes. A highly configurable client allows for information retrieval bypassing the interactive interface. This method is for example used by ALICE Offline to extract operational conditions after a run is completed. Last but not least, the software can be easily adopted to any underlying database structure and is therefore not limited to WINCCOA.

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

    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.

  17. Distributed medium access control in wireless networks

    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

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

    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.

  19. Explicit window-based transport control protocols in lossy environments

    de Vleeschouwer, C.; Frossard, P.

    2004-01-01

    This paper addresses efficient packet loss recovery by retransmission in window-based congestion control protocols. It builds on explicit congestion control mechanisms to decouple the packet loss detection from the congestion feedback signals. Implicit algorithms alternatively infer congestion from losses (which yields to window size reduction), and therefore do not allow to evaluate the performance of window-based transmission algorithms in lossy environments. We first propose a simple modif...

  20. Identity driven Capability based Access Control (ICAC) Scheme for the Internet of Things

    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...... to complexity and dynamics of device identities. ICAC is implemented for 802.11 and results shows that ICAC has less scalability issues and better performance analysis compared with other access control schemes. The ICAC evaluation by using security protocol verification tool shows that ICAC is secure against...

  1. Integrating Attributes into Role-Based Access Control

    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 of...... research recently. 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 takes into account the current contextual information while making the access control decisions....

  2. Cardea: Dynamic Access Control in Distributed Systems

    Lepro, Rebekah

    2004-01-01

    Modern authorization systems span domains of administration, rely on many different authentication sources, and manage complex attributes as part of the authorization process. This . paper presents Cardea, a distributed system that facilitates dynamic access control, as a valuable piece of an inter-operable authorization framework. First, the authorization model employed in Cardea and its functionality goals are examined. Next, critical features of the system architecture and its handling of the authorization process are then examined. Then the S A M L and XACML standards, as incorporated into the system, are analyzed. Finally, the future directions of this project are outlined and connection points with general components of an authorization system are highlighted.

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

    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.

  4. An energy-efficient rate adaptive media access protocol (RA-MAC) for long-lived sensor networks.

    Hu, Wen; Chen, Quanjun; Corke, Peter; O'Rourke, Damien

    2010-01-01

    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. PMID:22219675

  5. Implementation of a control protocol in the instrumentation field

    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.).

  6. Implementation of a control protocol in the instrumentation field

    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.)

  7. Research of user access control for networked manufacturing system

    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.

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

    Shen, Charles; Schulzrinne, Henning; 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 pro...

  9. Analysis and Comparison of Access Control Policies Validation Mechanisms

    Muhammad Aqib; Riaz Ahmed Shaikh

    2014-01-01

    Validation and verification of security policies is a critical and important task to ensure that access control policies are error free. The two most common problems present in access control policies are: inconsistencies and incompleteness. In order to detect such problems, various access control policy validation mechanisms are proposed by the researchers. However, comprehensive analysis and evaluation of the existing access control policy validation techniques is missing in the literature....

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

    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.

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

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

    2016-01-01

    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. PMID:27128923

  12. Cryptanalysis on Cheng et al. protocol

    Thakur, Tejeshwari

    2016-06-01

    Deployment of new node in any wireless sensor network is a sensitive task. This is the reason why, an Access Control Protocol is required in WSN. In this paper, we demonstrate that Access Control Protocol proposed by Cheng et al.[1] for Wireless Sensor Network is insecure. The reason is that this protocol fails to resist the active attack.

  13. Serial interface through stream protocol on EPICS platform for distributed control and monitoring

    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 MEDM (Motif Editor and Display Manager) and ALH (Alarm Handler) 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. (author)

  14. [Access to birth control: a world estimate].

    Blanco, C

    1988-04-01

    The populations of the developed countries have easy access to contraception, but adequate family planning services are lacking in 80 of 93 recently studied Third World countries. 58% of the population of the developing world lives in these 80 countries. 43% or 372 million of the world's reproductive aged couples use modern and safe contraception. Of these, 102 million live in industrialized countries, about 146 million in the People's Republic of China, and 124 million in other developing countries. Only 27% of couples in developing countries apart from China use modern contraception. Abortion continues to be the most used method of fertility control. About 33 million legal abortions and 27 million illegal abortions are performed annually. Some 250 million women in developing countries who do not desire pregnancy are without family planning information or services. 1 year of protection costs about US $20 per couple in a developing country. Governments of developed countries spend about US $1.5 billion on family planning programs, of which about $500 million is slated for external aid to population programs. An additional investment of $5 billion is needed to provide family planning services to the 250 million women needing them. The 15 most populated industrialized countries which account for 91% of the population of the developed world mostly have good or excellent access to family planning services and information, although some comparatively minor problems may persist. Access to contraception in the countries of Eastern Europe is considered only good because of governmental restrictions on sterilization. Access is hampered in Japan by unavailability of some types of IUDs and pills and severe restrictions on sterilization. Family planning services are only average in the USSR because of poor quality and irregular supplies of modern contraceptives, especially in rural areas. Abortion, although not always easy to arrange because of bureaucratic delays, remains the

  15. Break-glass handling exceptional situations in access control

    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

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

    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.

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

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

    2013-01-01

    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...... 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...... Authentication and Capability based Access Control (IACAC) model with protocol evaluation and performance analysis. To protect IoT from man-in-the-middle, replay and denial of service (Dos) attacks, the concept of capability for access control is introduced. The novelty of this model is that, it presents...

  18. Delegation in Role Based Access Control Model for Workflow Systems

    Prasanna H Bammigatti

    2008-03-01

    Full Text Available Role -based access control (RBAC has been introduced in the last few years, and offers a powerful means of specifying access control decisions. The model of RBAC usually assumes that, if there is a role hierarchy then access rights are inherited upwards through the hierarchy. In organization workflow the main threat is of access control. The Role based access control is one of the best suitable access control model one can think of. It is not only the role hierarchies but also other control factors that affect the access control in the workflow. The paper discusses the control factors and role hierarchies in workflow and brings a new model of RBAC. This paper also over comes the conflicts and proves that the system is safe by applying the new model to the workflow

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

    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.

  20. Microcontroller Protocol for Secure Broadcast in Controller Area Networks

    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

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

    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.

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

    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.

  3. An access control architecture for metropolitan area wireless networks

    Friday, Adrian; Wu, Maomao; Schmid, Stefan; Finney, Joseph; Cheverst, Keith; Davies, Nigel

    2001-01-01

    This paper presents a novel wireless access point architecture designed to support the development of next generation mobile context-aware applications over metropolitan scale areas. In addition, once deployed, this network will allow ordinary citizens secure, accountable and convenient access to the Internet from their local city and campus environments. The proposed architecture is based on an approach utilising a modified Mobile IPv6 protocol stack that uses packet marking and network leve...

  4. Attributes Enhanced Role-Based Access Control Model

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

    2015-01-01

    Attribute-based access control (ABAC) and role-based access control (RBAC) are currently the two most popular access control models. Yet, they both have known limitations and offer features com- plimentary to each other. Due to this fact, integration of RBAC and ABAC has recently emerged 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...... decisions but is also suitable for applications where access to resources is controlled by exploiting contents of the resources in the policy....

  5. Evolution of the Data Access Protocol in Response to Community Needs

    Gallagher, J.; Caron, J. L.; Davis, E.; Fulker, D.; Heimbigner, D.; Holloway, D.; Howe, B.; Moe, S.; Potter, N.

    2012-12-01

    Under the aegis of the OPULS (OPeNDAP-Unidata Linked Servers) Project, funded by NOAA, version 2 of OPeNDAP's Data Access Protocol (DAP2) is being updated to version 4. DAP4 is the first major upgrade in almost two decades and will embody three main areas of advancement. First, the data-model extensions developed by the OPULS team focus on three areas: Better support for coverages, access to HDF5 files and access to relational databases. DAP2 support for coverages (defined as a sampled functions) was limited to simple rectangular coverages that work well for (some) model outputs and processed satellite data but that cannot represent trajectories or satellite swath data, for example. We have extended the coverage concept in DAP4 to remove these limitations. These changes are informed by work at Unidata on the Common Data Model and also by the OGC's abstract coverages specification. In a similar vein, we have extended DAP2's support for relations by including the concept of foreign keys, so that tables can be explicitly related to one another. Second, the web interfaces - web services - that provides access to data using via DAP will be more clearly defined and use other (, orthogonal), standards where they are appropriate. An important case is the XML interface, which provides a cleaner way to build other response media types such as JSON and RDF (for metadata) and to build support for Atom, thus simplify the integration of DAP servers with tools that support OpenSearch. Input from the ESIP federation and work performed with IOOS have informed our choices here. Last, DAP4-compliant servers will support richer data-processing capabilities than DAP2, enabling a wider array of server functions that manipulate data before returning values. Two projects currently are exploring just what can be done even with DAP2's server-function model: The MIIC project at LARC and OPULS itself (with work performed at the University of Washington). Both projects have demonstrated that

  6. Design and Implementation of a Web-based Monitoring System by using EPICS Channel Access Protocol

    Proton Engineering Frontier Project (PEFP) has developed a 20MeV proton accelerator, and established a distributed control system based on EPICS for sub-system components such as vacuum unit, beam diagnostics, and power supply system. The control system includes a real-time monitoring and alarm functions. From the aspect of a efficient maintenance of a control system and a additional extension of subsystems, EPICS software framework was adopted. In addition, a control system should be capable of providing an easy access for users and a real-time monitoring on a user screen. Therefore, we have implemented a new web-based monitoring server with several libraries. By adding DB module, the new IOC web monitoring system makes it possible to monitor the system through the web. By integrating EPICS Channel Access (CA) and Database libraries into a Database module, the web-based monitoring system makes it possible to monitor the sub-system status through user's internet browser. In this study, we developed a web based monitoring system by using EPICS IOC (Input Output Controller) with IBM server

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

    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. PMID:23853128

  8. Implementation of the quality control protocol in Crawls

    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)

  9. Verifying Resource Access Control on Mobile Interactive Devices

    Besson, Frédéric; Dufay, Guillaume; Jensen, Thomas; Pichardie, David

    2010-01-01

    A model of resource access control is presented in which the access control to resources can employ user interaction to obtain the necessary permissions. This model is inspired by and improves on the Java security architecture used in Java-enabled mobile telephones. We extend the Java model to include access control permissions with multiplicities in order to allow to use a permission a certain number of times. We define a program model based on control flow graphs together with its operation...

  10. Implementation of Quality Control Protocol in Mammography: A Serbian Experience

    Mammography is method of choice for early detection of breast cancer. In Serbia, mammography is performed only clinically, although there is a long term plan to introduce mammography as screening method. Currently there are 60 mammography units in practice in Serbia, resulting with 70 000 mammographies annually. The purpose of this paper is preliminary evaluation of the mammography practice in Serbia, having in mind the annual number of examinations and fact that part of examination is performed on women without any clinical signs. For pilot implementation of Quality Control (QC) protocol in mammography, five hospitals with highest workload have been selected, representing the typical mammography practice in Serbia. Developed QC protocol, based on European guidelines for quality assurance in breast cancer screening and diagnosis, actual practice and resources, includes equipment testing and maintenance, staff training and QC management and allocation of responsibilities. Subsequently, it should be applied on the national scale. The survey demonstrated considerable variations in technical parameters that affect image quality and patients doses. Mean glandular doses ranged from 0.12 to 2.8 mGy, while reference optical density ranged from 1.2 to 2.8. Main problems were associated with film processing, viewing conditions and optical density control. The preliminary survey of mammography practice highlighted the need for optimization of radiation protection and training of operating staff, although the survey itself was very valuable learning process for all participants. Furthermore, systematic implementation of QC protocol should provide reliable performance of mammography units and maintain satisfactory image quality and keep patient doses as low as reasonably practical.(author)

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

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

    2014-01-01

    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. PMID:25123464

  12. A field exercise course to train IAEA Safeguards inspectors in implementing the additional protocol and performing complementary access activities

    The International Atomic Energy Agency (IAEA) Department of Safeguards has the task of implementing the Additional Protocol (AP) in the Member States that have signed agreements bringing that treaty into force. The IAEA inspector under the traditional INFCIRC/153 safeguards has been an accountant focused on the declared nuclear material stores of a Member State. The INFCIRC/540 Strengthened Safeguards System (SSS) provides the Agency and its inspectors with the right to investigate a Member State's nuclear programme to see if all declared activities are in order and no undeclared activities exist. This broadening of the scope of the inspector's responsibilities has changed the training of the inspectors to orient them to being an investigator compared to an accountant. The Safeguards training department has created a curriculum of courses that provides the background to train the inspectorate into this new inspection regime. The United States Support Program (USSP) has contributed to this curriculum by putting together a course at Brookhaven National Laboratory (BNL) in Additional Protocol Complementary Access (APCA) to give the IAEA the opportunity to provide inspectors a necessary field exercise in a realistic environment at a research site. Brookhaven National Laboratory contains three shutdown nuclear research reactors, operating particle accelerators, hot cells, radioactive waste storage, laser laboratories, and magnet production facilities on a large site very similar to numerous research facilities around the world situated in non-nuclear weapon states (NNWS). The USSP Team created an Article 2 declaration containing annotated maps of the site, descriptions of the buildings on site, satellite and aerial photographs of the area, and a declaration of research activities on the site. The declaration is as realistic to actual BNL research except that proprietary and security concerns of the BNL site have been taken into account. The USSP Team felt the best

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

    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...

  14. A Formal Model of Access Control for Mobile Interactive Devices

    Besson, Frédéric; Dufay, Guillaume; Jensen, Thomas

    2006-01-01

    This paper presents an access control model for programming applications in which the access control to resources can employ user interaction to obtain the necessary permissions. This model is inspired by and improves on the Java security architecture used in Javaenabled mobile telephones. We consider access control permissions with multiplicities in order to allow to use a permission a certain number of times. An operational semantics of the model and a formal definition of what it means for...

  15. ACADA: Access Control-driven Architecture with Dynamic Adaptation

    Pereira, Óscar Narciso Mortágua; Rui L. Aguiar; Santos, Maribel Yasmina

    2012-01-01

    Programmers of relational database applications use software solutions (Hibernate, JDBC, LINQ, ADO.NET) to ease the development process of business tiers. These software solutions were not devised to address access control policies, much less for evolving access control policies, in spite of their unavoidable relevance. Currently, access control policies, whenever implemented, are enforced by independent components leading to a separation between policies and their enf...

  16. Error Resistant Real-Time Transport Control Protocol

    S. Shahbazi

    2009-01-01

    Full Text Available Problem statement: Real-time Transport Control Protocol (RTCP protocol has been the subject of various criticisms due its problematic performance in large-scale networks. S-RTCP is a protocol with high potential as it has proved to be able to solve many problems of RTCP. It has numerous flaws on its own. This study aimed at dealing with flaws of S-RTCP and improving it in terms of stability and packet loss. Approach: A new proposed scheme was designed. Modifications included designing multi-manager scheme, improving parent-seeking procedures, reducing distribution of request packets, reforming the design to be independent from TTL, adding methods to check on sanity of manager nodes. This study considered packet loss ratio of below 2% as desirable. Results: ER-RTCP comparing to legacy RTCP in terms of packet loss using NS-2 in four different scenarios revealed improvements between 73 and 88% for various scenarios. It also kept packet loss rate below 2% for all scenarios. Comparison of ER-RTCP to S-RTCP showed that based on different α (stability of each single manager values, ER-RTCP was more stable as it showed more resistance to entire scheme breakdown (β. ER-RTCP's parent-seeking procedure, as modeled scenario revealed a packet generation reduction of 97%, compared to S-RTCP’s. In occurrence of parent AG leave or loss, ER-RTCP reduced request packet generation by 95%. Allowance of AG dismissing in ER-RTCP, avoided occurrence of packet loss, as sample scenario showed S-RTCP experiencing packet loss of 3.5% while ER-RTCP kept packet loss at zero in theory. Conclusion: Proposed design improved S-RTCP in terms of reduction of packet loss and stability.

  17. Performance analysis of multichannel medium access control algorithms for opportunistic spectrum access

    Pawelczak, P.; Pollin, S.; So, H.-S.W.; Bahai, A.R.S.; Prasad, R.V.; Hekmat, R.

    2009-01-01

    In this paper, different control channel (CC) implementations for multichannel medium access control (MAC) algorithms are compared and analyzed in the context of opportunistic spectrum access (OSA) as a function of spectrum-sensing performance and licensed user activity. The analysis is based on a d

  18. CONTEXT BASED ACCESS CONTROL MODEL FOR PROTECTING PERVASIVE ENVIRONMENT

    V. Nirmalrani

    2014-04-01

    Full Text Available -In Pervasive Computing, access control is a critical issue which gives many opportunities for users to access and share the resources anytime and anywhere in a more easiest way. Pervasive Computing Environments are heterogeneous and dynamic sensor-rich environments characterized by frequent and unpredictable changes on users, resources, and environment situations. These environments call the access control solutions that allow dynamic adjustments of access permissions based on information describing the conditions of these entities (context, such as location and time. Some existing models attempt to identify context information which is used as an optional attribute for limiting the scope of access control permissions. However, these approaches normally exploit identities and roles dynamically assigned to the users in order to grant access permissions, which is an inappropriate solution for open and dynamic environments. Those environments cannot assume the existence of predefined roles and user-role associations. Hence the access permissions are claimed and assigned to the users only based on context information, which characterizing the three most important entities of any access control framework: owners, requestors, and resources. Thus, this paper proposes a generalized context-based access control model for making access control decisions completely based on context information, offering seven types of context-based access control policies. The proposed model also takes into account the privacy requirements when enforcing access control policies, such as the support to purposes and obligations. In addition this paper proposes the integration of mechanism to detect / resolve dynamic and static conflict on context-based access control policies.

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

    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

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

    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...... information and secure federated IoT, this proposed model provides scalability, flexibility, and secure authority delegation for highly distributed system. The protocol evaluation results show that the capability creation and access mechanism of CCAAC is secure against a rigorous man-in-the-middle attack, e...

  1. Law-Aware Access Control and its Information Model

    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...

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

    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. Efficacy and cost effectiveness of telemedicine for improving access to care in the Paris region: study protocols for eight trials

    Charrier, Nathanael; Zarca, Kevin; Durand-Zaleski, Isabelle; Calinaud, Christine; ,

    2016-01-01

    Background With the development of information and communication technologies, telemedicine has been proposed as a way to improve patient management by facilitating access to appropriate diagnosis and treatment. The Paris Ile de France Regional Health Agency is currently funding a comprehensive program of telemedicine experiments. This article describes the protocols for the evaluation of the implementation of telemedicine in the Paris region. Methods/design Over 2,500 patients have been incl...

  4. A Quantitative Evaluation Method of Satellite Network Control Protocol based on Multi-attribute Utility Theory

    Zhu Jun

    2016-01-01

    Full Text Available Satellite network control protocol plays an important part in satellite communication system. Different design schemes of protocol have very different protocol attribute values. It is difficult to select a proper protocol solution from many solution alternatives with quite different protocol attributes, especially some mutual conflicted protocol attributes. Thereupon, this paper provides a multi-attribute utility theory based quantitative method to evaluate these protocol design schemes, in order to make a wise decision on how to select protocol solution. This method introduces several critical protocol attributes by utilizing a Petri net model, and aggregates them into a decision making matrix. On the basis of multi-attribute utility theory, quantitative evaluation values are achieved with the support of user attribute preference weight vectors. In the end, the paper presents experiments and discussions.

  5. Distributed Role-based Access Control for Coaliagion Application

    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.

  6. Dynamic User Role Assignment in Remote Access Control

    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,

  7. Analysis of Access Control Policies in Operating Systems

    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…

  8. Analysis and Comparison of Access Control Policies Validation Mechanisms

    Muhammad Aqib

    2014-12-01

    Full Text Available Validation and verification of security policies is a critical and important task to ensure that access control policies are error free. The two most common problems present in access control policies are: inconsistencies and incompleteness. In order to detect such problems, various access control policy validation mechanisms are proposed by the researchers. However, comprehensive analysis and evaluation of the existing access control policy validation techniques is missing in the literature. In this paper, we have provided a first detailed survey of this domain and presented the taxonomy of the access control policy validation mechanisms. Furthermore, we have provided a qualitative comparison and trend analysis of the existing schemes. From this survey, we found that only few validation mechanisms exist that can handle both inconsistency and incompleteness problem. Also, most of the policy validation techniques are inefficient in handling continuous values and Boolean expressions.

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

    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.

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

    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.

  11. Network Coding-Based Congestion Control at Network Layer: Protocol Design and Evaluation

    Zsuzsanna Ilona Kiss

    2011-01-01

    Full Text Available The paper proposes a congestion control protocol based on Network Coding (NC operations for thebutterfly topology. The proposed protocol defines XOR-based coding and decoding algorithms adapted tostreams having different rates and characteristics, as well as a signalling protocol required for dynamicactivation and deactivation of NC operations. Some general principles related to the integration of NCoperations into data transmission protocols are also discussed. The congestion control protocol proposedwas simulated in OMNeT++ and implemented in a real network to demonstrate its feasibility and to testthe functioning of the proposed coding and signalling algorithm in different scenarios.

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

    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.

  13. A novel user authentication and key agreement protocol for accessing multi-medical server usable in TMIS.

    Amin, Ruhul; Biswas, G P

    2015-03-01

    Telecare Medical Information System (TMIS) makes an efficient and convenient connection between patient(s)/user(s) at home and doctor(s) at a clinical center. To ensure secure connection between the two entities (patient(s)/user(s), doctor(s)), user authentication is enormously important for the medical server. In this regard, many authentication protocols have been proposed in the literature only for accessing single medical server. In order to fix the drawbacks of the single medical server, we have primarily developed a novel architecture for accessing several medical services of the multi-medical server, where a user can directly communicate with the doctor of the medical server securely. Thereafter, we have developed a smart card based user authentication and key agreement security protocol usable for TMIS system using cryptographic one-way hash function. We have analyzed the security of our proposed authentication scheme through both formal and informal security analysis. Furthermore, we have simulated the proposed scheme for the formal security verification using the widely-accepted AVISPA (Automated Validation of Internet Security Protocols and Applications) tool and showed that the scheme is secure against the replay and man-in-the-middle attacks. The informal security analysis is also presented which confirms that the protocol has well security protection on the relevant security attacks. The security and performance comparison analysis confirm that the proposed protocol not only provides security protection on the above mentioned attacks, but it also achieves better complexities along with efficient login and password change phase. PMID:25681100

  14. Distributed Access Control Policies for Spectrum Sharing

    Baldini, Gianmarco; NAI-FOVINO Igor; Trombetta, Alberto; Braghin, Stefano

    2012-01-01

    Cognitive Radio (CR) is a novel wireless communication technology that allows for adaptive configuration of the reception parameters of a terminal, based on the information collected from the environment. Cognitive radio (CR) technology can be used in innovative spectrum management approaches like spectrum sharing, where radio frequency spectral bands can be shared among various users through a dynamic exclusive-use spectrum access model. Spectrum sharing can be applied to various...

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

    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.

  16. Controlled trial of an open-access physiotherapy service

    Gentle, P. H.; Herlihy, P. J.; Roxburgh, I. O.

    1984-01-01

    A randomized controlled trial of outpatient open-access physiotherapy was carried out at West Cornwall Hospital during 1979/80. The referral rate to consultant outpatient clinics for those patients offered open-access physiotherapy was considerably lower than for the control group (17 per cent and 56 per cent respectively). Patients using the service received physiotherapy promptly although this did not result in shorter treatments. Those of the control group who eventually received physiothe...

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

    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)

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

    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.

  19. An error-resistant linguistic protocol for air traffic control

    Cushing, Steven

    1989-01-01

    The research results described here are intended to enhance the effectiveness of the DATALINK interface that is scheduled by the Federal Aviation Administration (FAA) to be deployed during the 1990's to improve the safety of various aspects of aviation. While voice has a natural appeal as the preferred means of communication both among humans themselves and between humans and machines as the form of communication that people find most convenient, the complexity and flexibility of natural language are problematic, because of the confusions and misunderstandings that can arise as a result of ambiguity, unclear reference, intonation peculiarities, implicit inference, and presupposition. The DATALINK interface will avoid many of these problems by replacing voice with vision and speech with written instructions. This report describes results achieved to date on an on-going research effort to refine the protocol of the DATALINK system so as to avoid many of the linguistic problems that still remain in the visual mode. In particular, a working prototype DATALINK simulator system has been developed consisting of an unambiguous, context-free grammar and parser, based on the current air-traffic-control language and incorporated into a visual display involving simulated touch-screen buttons and three levels of menu screens. The system is written in the C programming language and runs on the Macintosh II computer. After reviewing work already done on the project, new tasks for further development are described.

  20. PANATIKI: A Network Access Control Implementation Based on PANA for IoT Devices

    Antonio F. Gomez Skarmeta

    2013-11-01

    Full Text Available 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. PANATIKI: a network access control implementation based on PANA for IoT devices.

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

    2013-01-01

    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. PMID:24189332

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

    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.

  3. Geospacial information utilized under the access control strategy

    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.

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

    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.

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

    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.

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

    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.

  7. Joint protocol relating to the application of the Vienna Convention and the Paris Convention. Status list as of 12 September 2000. Signature, ratification, acceptance, approval or accession

    The document presents the status of signature, ratification, acceptance, approval or accession of the Joint Protocol Relating to the Application of the Vienna Convention and the Paris Convention as of 12 September 2000. The Joint Protocol entered into force on 27 April 1992

  8. Modeling Access Control Policy of a Social Network

    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.

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

    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

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

    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.

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

    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.

  12. Mining Attribute-Based Access Control Policies from Logs

    Xu, Zhongyuan; Stoller, Scott,

    2014-01-01

    Attribute-based access control (ABAC) provides a high level of flexibility that promotes security and information sharing. ABAC policy mining algorithms have potential to significantly reduce the cost of migration to ABAC, by partially automating the development of an ABAC policy from information about the existing access-control policy and attribute data. This paper presents an algorithm for mining ABAC policies from operation logs and attribute data. To the best of our knowledge, it is the ...

  13. A United Access Control Model for Systems in Collaborative Commerce

    Ruo-Fei Han; Hou-Xiang Wang; Qian Xiao; Xiao-Pei Jing; Hui Li

    2009-01-01

    The latest researches on access control model are dramatically different from conventional ones. Nowadays, most attention is paid to accessing across organizational boundaries. So, how to identify the applicant and determine authorization with limited information; how to express and exchange control rules expediently; how to protect confidential information and enhance collaboration simultaneously, are the most concerned problems. However, for large commercial organizations, a fine management...

  14. Reinforcement Learning Technique in Multiple Motorway Access Control Strategy Design

    Veljanovska, Kostandina; M. Bombol, Kristi; Maher, Tomaž

    2010-01-01

    An appropriately designed motorway access control can decrease the total travel time spent in the system up to 30% and consequently increase the merging operations safety. To date, implemented traffic responsive motorway access control systems have been of local or regulatory type and not truly adaptive in the real sense of the meaning. Hence, traffic flow can be influenced positively by numerous intelligent transportation system (ITS) techniques. In this paper a contemporary approach is pres...

  15. PMT Dark Noise Monitoring System for Neutrino Detector Borexino Based on the Devicenet Protocol and WEB-Access

    Monitoring of PMT dark noise in a neutrino detector BOREXINO is a procedure that indicates condition of the detector. Based on CAN industrial network, top level DeviceNet protocol and WEB visualization, the dark noise monitoring system having 256 channels for the internal detector and for the external muon veto was created. The system is composed as a set of controllers, converting the PMT signals to frequency and transmitting them over Can network. The software is the stack of the DeviceNet protocols, providing the data collecting and transporting. Server-side scripts build web pages of user interface and graphical visualization of data

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

    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.

  17. Implementing ‘Mutually Supportive’ Access and Benefit Sharing Mechanisms Under the Plant Treaty, Convention on Biological Diversity, and Nagoya Protocol

    Michael Halewood et. al.

    2013-06-01

    Full Text Available The International Treaty on Plant Genetic Resources for Food and Agriculture (ITPGRFA and the Convention on Biological Diversity (CBD commit their member states to implement very different access and benefit-sharing systems: one system, under the ITPGRFA, is designed to encourage international pooling and sharing of genetic diversity; the other system, under the CBD, is designed to maximise each country’s sovereign control over their genetic resources. Progress in domestic implementation of both systems has been relatively slow. One factor contributing to delays is that policy makers in many countries are uncertain about how to address the interface between these two access and benefit-sharing systems. Based on research and policy development experiences in several countries, the authors first identify the issues national policy-makers need to address, and the steps they need to follow, to implement the multilateral system of access and benefit sharing under the ITPGRFA. Second, the authors analyse the points of intersection, at the national level, between the ITPGRFA’s multilateral system and access and benefit-sharing, and mechanisms developed (or being developed pursuant to the Convention on Biological Diversity and its recently adopted Nagoya Protocol. Third, the authors analyse factors that are contributing to the lack of coordination, in many countries, between the national public environment and agriculture agencies that have mandates to lead national implementation of these international agreements.

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

    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.

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

    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.

  20. Software application for quality control protocol of mammography systems

    Considering the fact that the Quality Control of the technological process of the mammographic system involves testing of a large number of parameters, it is clearly evident that there is a need for using the information technology for gathering, processing and storing of all the parameters that are result of this process. The main goal of this software application is facilitation and automation of the gathering, processing, storing and presenting process of the data related to the qualification of the physical and technical parameters during the quality control of the technological process of the mammographic system. The software application along with its user interface and database has been made with the Microsoft Access 2003 application which is part of the Microsoft Office 2003 software packet and has been chosen as a platform for developing because it is the most commonly used office application today among the computer users in the country. This is important because it will provide the end users a familiar environment to work in, without the need for additional training and improving the computer skills that they posses. Most importantly, the software application is easy to use, fast in calculating the parameters needed and it is an excellent way to store and display the results. There is a possibility for up scaling this software solution so it can be used by many different users at the same time over the Internet. It is highly recommended that this system is implemented as soon as possible in the quality control process of the mammographic systems due to its many advantages.(Author)

  1. Access Control in Cloud Computing Environment

    Soorat Hussain

    2014-01-01

    Full Text Available Cloud Computing is a new technology which is directly connected with the internet which provide on demand self service internet infrastructure where a customer can pay and use only what is needed. Cloud Computing all services are managed by third party cloud service provider. Nowadays majority using static password to login into the system or access the online accounts in cloud but never change the password which is not secure . Since Cloud computing is a quite new subject, most of the cloud providers have not yet tighten up their security and still use insecure or complicated login method. Static password thoroughly investigated and found out that it is not completing the cloud computing security requirement. Proposed solution is One Time Password and One Day Password, OTP will get expire after two minutes, if user again login will request and receive new password via email and ODP will get expire after 24 hours and on request receive new password via email for new login session. OTP/ODP used with AES encryption. This paper focuses the authentication and transmission encryption in cloud computing services.

  2. OBLIVIOUS TRANSFER WITH ACCESS CONTROL AND IDENTITYBASED ENCRYPTION WITH ANONYMOUS KEY ISSUING

    Xu Lingling; Zhang Fangguo; Wen Yamin

    2011-01-01

    In ACM'CCS 2009,Camenisch,et al.proposed the Obhvious Transfer with Access Control (AC-OT) in which each item is associated with an attribute set and can only be available,on request,to the users who have all the attributes in the associated set.Namely,AC-OT achieves access control policy for conjunction of attributes.Essentially,the functionality of AC-OT is equivalent to the simplified version that we call AC-OT-SV:for each item,one attribute is associated with it,and it is requested that only the users who possess the associated attribute can obtain the item by queries.On one hand,AC-OT-SV is a special case of AC-OT when there is just one associated attribute with each item.On the other hand,any AC-OT can be realized by an AC-OT-SV.In this paper,we first present a concrete AC-OT-SV protocol which is proved to be secure in the model defined by Camenisch,et al..Then from the protocol,interestingly,a concrete Identity-Based Encryption (IBE) with Anonymous Key Issuing (AKI) is given which is just a direct application to AC-OT-SV.By comparison,we show that the AKI protocol we present is more efficient in communications than that proposed by Chow.

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

    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.

  4. Advancing Migrant Access to Health Services in Europe (AMASE): Protocol for a Cross-sectional Study

    Fakoya, I; Álvarez-Del Arco, D.; Monge, S; Copas, A J; Gennotte, A. F.; Volny-Anne, A.; Göpel, S.; Touloumi, G.; Prins, M; Barros, H; Staehelin, C.; del Amo, J.; Burns, F. M.

    2016-01-01

    BACKGROUND: Migrants form a substantial proportion of the population affected by the human immunodeficiency virus (HIV) epidemic in Europe, yet HIV prevention for this population is hindered by poor understanding of access to care and of postmigration transmission dynamics. OBJECTIVE: We present the design and methods of the advancing Migrant Access to health Services in Europe (aMASE) study, the first European cross-cultural study focused on multiple migrant populations. It aims to identify ...

  5. A Random Access Protocol for Pilot Allocation in Crowded Massive MIMO Systems

    Björnson, Emil; de Carvalho, Elisabeth; Sørensen, Jesper H.; Larsson, Erik G.; Popovski, Petar

    2016-01-01

    The Massive MIMO (multiple-input multiple-output) technology has a great potential to manage the rapid growth of wireless data traffic. Massive MIMO achieve tremendous spectral efficiency by spatial multiplexing of many tens of user equipments (UEs). These gains are only achieved in practice if many more UEs can connect efficiently to the network than today. As the number of UEs increases, while each UE intermittently accesses the network, the random access functionality becomes essential to ...

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

    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 by...... access 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. Implementation to spanish protocol of quality control of accelerators to daily control of electron beams

    A revised procedure for daily control of the electron beams to make measurements more meaningful physically, having a better reproducibility and more in line with the recommendations of the Spanish Protocol for Quality Control in Electron Linear Accelerators Clinical Use. The daily quality control beams of high energy electrons that had been done so far was the finding that the record of a series of measures (symmetry, uniformity, stability, energy, beam central dose) were within tolerance values established. The amendment is to check the beam quality by directly measuring changes in absorption depth at which the dose is reduced to half its maximum value, R50.

  8. Specification of a Collision-Free CSMA MAC Protocol for Wireless LANs: the CANlike protocol

    Juanole, Guy; Nguyen, Xuan Hung; Mouney, Gérard

    2013-01-01

    Collision-free Medium Access Control (MAC) protocols based on Carrier Sense Multiple Access (CSMA) and priorities associated to the frames are interesting solutions in considering real-time traffic in a wireless context.We have already presented such a protocol using priorities represented by the BlackBurst technique [1]. The goal of this paper is, at first and mainly, to specify another such protocol, named CANlike, which is an adaptation of the wired CAN bus protocol to the wireless context...

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

    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.

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

    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

  11. Secure Remote Access Issues in a Control Center Environment

    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.

  12. A United Access Control Model for Systems in Collaborative Commerce

    Ruo-Fei Han

    2009-06-01

    Full Text Available The latest researches on access control model are dramatically different from conventional ones. Nowadays, most attention is paid to accessing across organizational boundaries. So, how to identify the applicant and determine authorization with limited information; how to express and exchange control rules expediently; how to protect confidential information and enhance collaboration simultaneously, are the most concerned problems. However, for large commercial organizations, a fine management of internal functions is of the same importance as external service management. It is very troublesome to control authorizations merely with attributes and composition of policies introduced from attribute-based access control (ABAC. So, we introduce a united access control model for systems in collaborative commerce, combining the advantages of conventional role-based access control (RBAC, task-based authentication control (TBAC and that of recent ABAC and automated trust negotiation (ATN. Innovational ideas in the model are analyzed, and the implement architecture is discussed. The paper concludes with a summary of the united model’s benefits and future work.

  13. SPS access control system a new user interface

    Riesco, T

    1999-01-01

    This document describes the project to implement at CERN new trends in industrial control systems and integrate new requirements and functions requested by users. This project will be the testing ground for the specification of procedures in the Access Control and Machine Interlock of LHC. The last modification in the Access Control System to the primary beam areas was made in 1995, and this new project is to improve the fields of personal security, access security and the introduction of modern communication networks used in the industrial control systems. Inside the cycle model of project life, it is at the present time in the test phase in terms of security and exploitation inside the Accelerator Decelerator (AD) project. The presence of Authorization Management System (AMS) to guarantee the automatic information distribution of authorizations to controlled areas is in line with this project.

  14. Face recognition in controlled access points

    Mur Escartín, Olga

    2009-01-01

    The thesis consist in the study and evaluation of different methods for face recognition. The final objective is to select the most suitable techniques for face detection and recognition. Some of these techniques will be intergrated in a real time demontrator which will be a preliminary prototype that will have to work in controlled conditions (for ilumination and pose) and with reduced databases. The demonstrator will be done in Matlab and the main image acquisition rotines and face detectio...

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

    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.

  16. Role Based Access Control system in the ATLAS experiment

    Valsan, M L; The ATLAS collaboration; Lehmann Miotto, G; Scannicchio, D A; Schlenker, S; Filimonov, V; Khomoutnikov, V; Dumitru, I; Zaytsev, A S; Korol, A A; Bogdantchikov, A; Caramarcu, C; Ballestrero, S; Darlea, G L; Twomey, M; Bujor, F; Avolio, G

    2011-01-01

    The complexity of the ATLAS experiment motivated the deployment of an integrated Access Control System in order to guarantee safe and optimal access for a large number of users to the various software and hardware resources. Such an integrated system was foreseen since the design of the infrastructure and is now central to the operations model. In order to cope with the ever growing needs of restricting access to all resources used within the experiment, the Roles Based Access Control (RBAC) previously developed has been extended and improved. The paper starts with a short presentation of the RBAC design, implementation and the changes made to the system to allow the management and usage of roles to control access to the vast and diverse set of resources. The paper continues with a detailed description of the integration across all areas of the system: local Linux and Windows nodes in the ATLAS Control Network (ATCN), the Linux application gateways offering remote access inside ATCN, the Windows Terminal Serv...

  17. Role Based Access Control System in the ATLAS Experiment

    Valsan, M L; The ATLAS collaboration; Lehmann Miotto, G; Scannicchio, D A; Schlenker, S; Filimonov, V; Khomoutnikov, V; Dumitru, I; Zaytsev, A S; Korol, A A; Bogdantchikov, A; Avolio, G; Caramarcu, C; Ballestrero, S; Darlea, G L; Twomey, M; Bujor, F

    2010-01-01

    The complexity of the ATLAS experiment motivated the deployment of an integrated Access Control System in order to guarantee safe and optimal access for a large number of users to the various software and hardware resources. Such an integrated system was foreseen since the design of the infrastructure and is now central to the operations model. In order to cope with the ever growing needs of restricting access to all resources used within the experiment, the Roles Based Access Control (RBAC) previously developed has been extended and improved. The paper starts with a short presentation of the RBAC design, implementation and the changes made to the system to allow the management and usage of roles to control access to the vast and diverse set of resources. The paper continues with a detailed description of the integration across all areas of the system: local Linux and Windows nodes in the ATLAS Control Network (ATCN), the Linux application gateways offering remote access inside ATCN, the Windows Terminal Serv...

  18. A Survey of Access Control Models in Wireless Sensor Networks

    Htoo Aung Maw

    2014-06-01

    Full Text Available Wireless sensor networks (WSNs have attracted considerable interest in the research community, because of their wide range of applications. However, due to the distributed nature of WSNs and their deployment in remote areas, these networks are vulnerable to numerous security threats that can adversely affect their proper functioning. Resource constraints in sensor nodes mean that security mechanisms with a large overhead of computation and communication are impractical to use in WSNs; security in sensor networks is, therefore, a challenge. Access control is a critical security service that offers the appropriate access privileges to legitimate users and prevents illegitimate users from unauthorized access. However, access control has not received much attention in the context of WSNs. This paper provides an overview of security threats and attacks, outlines the security requirements and presents a state-of-the-art survey on access control models, including a comparison and evaluation based on their characteristics in WSNs. Potential challenging issues for access control schemes in WSNs are also discussed.

  19. A Multi-Domain Access Control Infrastructure Based on Diameter and EAP

    Ben Ayed, Souheil; Teraoka, Fumio

    The evolution of Internet, the growth of Internet users and the new enabled technological capabilities place new requirements to form the Future Internet. Many features improvements and challenges were imposed to build a better Internet, including securing roaming of data and services over multiple administrative domains. In this research, we propose a multi-domain access control infrastructure to authenticate and authorize roaming users through the use of the Diameter protocol and EAP. The Diameter Protocol is a AAA protocol that solves the problems of previous AAA protocols such as RADIUS. The Diameter EAP Application is one of Diameter applications that extends the Diameter Base Protocol to support authentication using EAP. The contributions in this paper are: 1) first implementation of Diameter EAP Application, called DiamEAP, capable of practical authentication and authorization services in a multi-domain environment, 2) extensibility design capable of adding any new EAP methods, as loadable plugins, without modifying the main part, and 3) provision of EAP-TLS plugin as one of the most secure EAP methods. DiamEAP Server basic performances were evaluated and tested in a real multi-domain environment where 200 users attempted to access network using the EAP-TLS method during an event of 4 days. As evaluation results, the processing time of DiamEAP using the EAP-TLS plugin for authentication of 10 requests is about 20ms while that for 400 requests/second is about 1.9 second. Evaluation and operation results show that DiamEAP is scalable and stable with the ability to handle more than 6 hundreds of authentication requests per second without any crashes. DiamEAP is supported by the AAA working group of the WIDE Project.

  20. Distributed Medium Access Control with SDMA Support for WLANs

    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.

  1. Public information: control, secret and right of access

    Carmem Lúcia Batista

    2012-01-01

    Recently, in November 2011, it was published the law on access to public information, legal and historic mark in the struggle for human rights in Brazil. This achievement is the result of a process marked by denial of access to public archives, as it was the case of the Araguaia Guerrilla, valuing the culture of secrecy, abuse of power and relations between public and private in Brazil. Thus, the aim of this paper is to present a brief history about the control of access to public information...

  2. Law-Aware Access Control and its Information Model

    Stieghahn, Michael; Engel, Thomas

    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 exa...

  3. Open Platform Strategies and Innovation: Granting Access vs. Devolving Control

    Kevin Boudreau

    2010-01-01

    This paper studies two fundamentally distinct approaches to opening a technology platform and their different impacts on innovation. One approach is to grant access to a platform and thereby open up markets for complementary components around the platform. Another approach is to give up control over the platform itself. Using data on 21 handheld computing systems (1990-2004), I find that granting greater levels of access to independent hardware developer firms produces up to a fivefold accele...

  4. User Behavior Trust Based Cloud Computing Access Control Model

    Jiangcheng, Qin

    2016-01-01

    Context. With the development of computer software, hardware, and communication technologies, a new type of human-centered computing model, called Cloud Computing (CC) has been established as a commercial computer network service. However, the openness of CC brings huge security challenge to the identity-based access control system, as it not able to effectively prevent malicious users accessing; information security problems, system stability problems, and also the trust issues between cloud...

  5. Authenticated Blind Issuing of Symmetric Keys for Mobile Access Control System without Trusted Parties

    Shin-Yan Chiou

    2013-01-01

    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 syst...

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

    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.

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

    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

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

    Wang Peng; Jiang Lingyun

    2015-01-01

    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...

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

    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.

  10. An Efficient Mutual Authentication and Access Control Scheme for Wireless Sensor Networks in Healthcare

    Xuan Hung Le

    2011-03-01

    Full Text Available Wireless sensor networks (WSNs will play an active role in the 21th Century Healthcare IT to reduce the healthcare cost and improve the quality of care. The protection of data confidentiality and patient privacy are the most critical requirements for the ubiquitous use of WSNs in healthcare environments. This requires a secure and lightweight user authentication and access control. Symmetric key - based access control is not suitable for WSNs in healthcare due to dynamic network topology, mobility, and stringent resource constraints. In this paper, we propose a secure, lightweight public key - based security scheme, Mutual Authentication and Access Control based on Elliptic curve cryptography (MAACE. MAACE is a mutual authentication protocol where a healthcare professional can authenticate to an accessed node (a PDA or medical sensor and vice versa. This is to ensure that medical data is not exposed to an unauthorized person. On the other hand, it ensures that medical data sent to healthcare professionals did not originate from a malicious node. MAACE is more scalable and requires less memory compared to symmetric key-based schemes. Furthermore, it is much more lightweight than other public key-based schemes. Security analysis and performance evaluation results are presented and compared to existing schemes to show advantages of the proposed scheme.

  11. Congestion control for vehicular delay tolerant network routing protocols

    Oham, Chuka Finbars

    2014-01-01

    The Vehicular Delay Tolerant Network (VDTN) is a special and challenging type of the Delay Tolerant Network because of its high mobility, frequent disconnections and nodal congestion features. These challenging features make it prone to congestion which leads to a considerable amount of message drops in the network. To minimize the impact of congestion in the network, we designed and implemented the Congestion Aware Spray and Wait (CASaW) routing protocol. We varied the buffer sizes of the no...

  12. IVOA Recommendation: Observation Data Model Core Components and its Implementation in the Table Access Protocol Version 1.0

    Louys, Mireille; Schade, David; Dowler, Patrick; Micol, Alberto; Durand, Daniel; Tody, Doug; Michel, Laurent; Salgado, Jesus; Chilingarian, Igor; Rino, Bruno; Santander, Juan de Dios; Skoda, Petr

    2011-01-01

    This document defines the core components of the Observation data model that are necessary to perform data discovery when querying data centers for observations of interest. It exposes use-cases to be carried out, explains the model and provides guidelines for its implementation as a data access service based on the Table Access Protocol (TAP). It aims at providing a simple model easy to understand and to implement by data providers that wish to publish their data into the Virtual Observatory. This interface integrates data modeling and data access aspects in a single service and is named ObsTAP. It will be referenced as such in the IVOA registries. There will be a separate document to cover the full Observation data model. In this document, the Observation Data Model Core Components (ObsCoreDM) defines the core components of queryable metadata required for global discovery of observational data. It is meant to allow a single query to be posed to TAP services at multiple sites to perform global data discovery...

  13. Random access MAC protocols and system monitoring methodology in wireless mesh networks.

    Huang, F.

    2008-01-01

    As an extension of wireless Ad Hoc 1 and sensor 2 networks, wireless mesh networks (WMN) 3 have recently been developed as a key solution to provide high-quality multimedia services and applications, such as voice, data and video, over wireless personal area networks (WPAN) 4, wireless local area network (WXAN) 5 and wireless metropolitan area network (WMAN) 6. A WMN usually has a hierarchical network infrastructure with backbone and access networks operated in both Ad Hoc and centralized mod...

  14. Based on asynchronous communication protocol of geographic space information service access mechanism research

    G. Chen; Zhao, J.; Gu, M; Li, D.

    2014-01-01

    At present, the traditional way of accessing to classified network in geographic spatial information services is using network gatekeeper and firewall etc. to ensure public and classified network communications links. However, the physical isolation between classified network and public network is crossed, which is bound to cause classified network potential security hazard. In Yunnan province space Land dynamic monitoring integration project, it proposed the point to point text m...

  15. Perspectives of People Living with HIV on Access to Health Care: Protocol for a Scoping Review

    Maybank, Allison; Hurley, Oliver; Modir, Hilary; Farrell, Alison; Marshall, Zack; Kendall, Claire; Johnston, Sharon; Hogel, Matthew; Rourke, Sean B; Liddy, Clare

    2016-01-01

    Background Strategies to improve access to health care for people living with human immunodeficiency virus (PLHIV) have demonstrated limited success. Whereas previous approaches have been informed by the views of health providers and decision-makers, it is believed that incorporating patient perspectives into the design and evaluations of health care programs will lead to improved access to health care services. Objective We aim to map the literature on the perspectives of PLHIV concerning access to health care services, to identify gaps in evidence, and to produce an evidence-informed research action plan to guide the Living with HIV program of research. Methods This scoping review includes peer-reviewed and grey literature from 1946 to May 2014 using double data extraction. Variations of the search terms “HIV”, “patient satisfaction”, and “health services accessibility” are used to identify relevant literature. The search strategy is being developed in consultation with content experts, review methodologists, and a librarian, and validated using gold standard studies identified by those stakeholders. The inclusion criteria are (1) the study includes the perspectives of PLHIV, (2) study design includes qualitative, quantitative, or mixed methods, and (3) outcome measures are limited to patient satisfaction, their implied needs, beliefs, and desires in relation to access to health care. The papers are extracted by two independent reviewers, including quality assessment. Data is then collated, summarized, and thematically analyzed. Results A total of 12,857 references were retrieved, of which 326 documents were identified as eligible in pre-screening, and 64 articles met the inclusion criteria (56% qualitative studies, 38% quantitative studies and 6% mixed-method studies). Only four studies were conducted in Canada. Data synthesis is in progress and full results are expected in June, 2016. Conclusions This scoping review will record and characterize the

  16. A Service Access Security Control Model in Cyberspace

    Qianmu, Li; Jie, Yin; Jun, Hou; Jian, Xu; Hong, Zhang; Yong, Qi

    A service access control model in cyberspace is proposed, which provides a generalized and effective mechanism of security management with some items constraint specifications. These constraint specifications are organized to form a construction, and an enact process is proposed to make it scalable and flexible to meet the need of diversified service application systems in cyberspace. The model of this paper erases the downward information flow by extended rules of read/write, which is the breakthrough of the limitations when applying the standard role-based access control in cyberspace.

  17. Access to Health Care and Control of ABCs of Diabetes

    Zhang, Xuanping; Bullard, Kai McKeever; Gregg, Edward W.; Beckles, Gloria L.; Williams, Desmond E.; Barker, Lawrence E; Albright, Ann L.; Imperatore, Giuseppina

    2012-01-01

    OBJECTIVE To examine the relationship between access to health care and diabetes control. RESEARCH DESIGN AND METHODS Using data from the National Health and Nutrition Examination Survey, 1999–2008, we identified 1,221 U.S. adults (age 18–64 years) with self-reported diabetes. Access was measured by current health insurance coverage, number of times health care was received over the past year, and routine place to go for health care. Diabetes control measures included the proportion of people...

  18. Privacy Preservation in Role-based Access Control Model

    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.

  19. Optical label-controlled transparent metro-access network interface

    Osadchiy, Alexey Vladimirovich

    control. Highlights of my research include my proposal and experimental proof of principle of an optical coherent detection based optical access network architecture providing support for a large number of users over a single distribution fiber; a spectral amplitude encoded label detection technique for......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...

  20. Controlling user access to electronic resources without password

    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.

  1. A Group-oriented Access Control Scheme for P2P Networks

    Wang Xiaoming

    2011-02-01

    Full Text Available A group-oriented access control scheme is proposed for P2P (peer to peer networks. In the proposed scheme, authentication control, admission control and revocation control are used in order to provide security services for P2P networks. Moreover, the proposed scheme can simply and efficient establish share key between two members without interactions, therefore it can perform secure communications with them. The analysis of security and performance shows that the proposed scheme not only can realize authentication and secure communication, but also can easily and efficiently add new group members and revoke malicious group members. Therefore, it is more efficient, and more practical protocol for P2P networks.

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

    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...

  3. Review of Access Control Models for Cloud Computing

    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 .

  4. Advancing Migrant Access to Health Services in Europe (AMASE): Protocol for a Cross-sectional Study

    Álvarez-del Arco, Débora; Monge, Susana; Copas, Andrew J; Gennotte, Anne-Francoise; Volny-Anne, Alain; Göpel, Siri; Touloumi, Giota; Prins, Maria; Barros, Henrique; Staehelin, Cornelia; del Amo, Julia; Burns, Fiona M

    2016-01-01

    Background Migrants form a substantial proportion of the population affected by the human immunodeficiency virus (HIV) epidemic in Europe, yet HIV prevention for this population is hindered by poor understanding of access to care and of postmigration transmission dynamics. Objective We present the design and methods of the advancing Migrant Access to health Services in Europe (aMASE) study, the first European cross-cultural study focused on multiple migrant populations. It aims to identify the structural, cultural, and financial barriers to HIV prevention, diagnosis, and treatment and to determine the likely country of HIV acquisition in HIV-positive migrant populations. Methods We delivered 2 cross-sectional electronic surveys across 10 countries (Belgium, France, Germany, Greece, Italy, the Netherlands, Portugal, Spain, Switzerland, and United Kingdom). A clinic survey aimed to recruit up to 2000 HIV-positive patients from 57 HIV clinics in 9 countries. A unique study number linked anonymized questionnaire data to clinical records data (viral loads, CD4 cell counts, viral clades, etc). This questionnaire was developed by expert panel consensus and cognitively tested, and a pilot study was carried out in 2 countries. A Web-based community survey (n=1000) reached those living with HIV but not currently accessing HIV clinics, as well as HIV-negative migrants. It was developed in close collaboration with a community advisory group (CAG) made up of representatives from community organizations in 9 of the participating countries. The CAG played a key role in data collection by promoting the survey to higher-risk migrant groups (sub-Saharan Africans, Latin Americans, men who have sex with men, and people who inject drugs). The questionnaires have considerable content overlap, allowing for comparison. Questions cover ethnicity, migration, immigration status, HIV testing and treatment, health-seeking behavior, sexual risk, and drug use. The electronic questionnaires

  5. SAT-based Distributed Reactive Control Protocol Synthesis for Boolean Networks

    Sahin, Yunus Emre; Ozay, Necmiye

    2016-01-01

    This paper considers the synthesis of distributed reactive control protocols for a Boolean network in a distributed manner. We start with a directed acyclic graph representing a network of Boolean subsystems and a global contract, given as an assumption-guarantee pair. Assumption captures the environment behavior, and guarantee is the requirements to be satisfied by the system. Local assumption-guarantee contracts, together with local control protocols ensuring these local contracts, are comp...

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

    Gareth W Daniel; Min Chen

    2003-01-01

    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...

  7. On TCP-based Session Initiation Protocol (SIP) Server Overload Control

    Shen, Charles; Schulzrinne, Henning

    2010-01-01

    The Session Initiation Protocol (SIP) server overload management has attracted interest since SIP is being widely deployed in the Next Generation Networks (NGN) as a core signaling protocol. Yet all existing SIP overload control work is focused on SIP-over-UDP, despite the fact that TCP is increasingly seen as the more viable choice of SIP transport. This paper answers the following questions: is the existing TCP flow control capable of handling the SIP overload problem? If not, why and how c...

  8. Design and Optimization of Wireless Remote Monitoring and Control System Using the ZigBee Protocol

    Zhang, Jingcheng

    2011-01-01

    This thesis presents the design and the optimization of a wireless remote monitoring and control system utilizing the ZigBee protocol. From the system architecture point of view, the remote wireless monitoring and control system is mainly combined by 3 parts, the wireless sensor network, the message gateway and the web service. In order to increase the system flexibility and the reconfigurability, each part communicates with each other by using the standard communication protocols. The wirele...

  9. Access Control of Web and Java Based Applications

    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.

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

    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...

  11. Research on a dynamic workflow access control model

    Liu, Yiliang; Deng, Jinxia

    2007-12-01

    In recent years, the access control technology has been researched widely in workflow system, two typical technologies of that are RBAC (Role-Based Access Control) and TBAC (Task-Based Access Control) model, which has been successfully used in the role authorizing and assigning in a certain extent. However, during the process of complicating a system's structure, these two types of technology can not be used in minimizing privileges and separating duties, and they are inapplicable when users have a request of frequently changing on the workflow's process. In order to avoid having these weakness during the applying, a variable flow dynamic role_task_view (briefly as DRTVBAC) of fine-grained access control model is constructed on the basis existed model. During the process of this model applying, an algorithm is constructed to solve users' requirements of application and security needs on fine-grained principle of privileges minimum and principle of dynamic separation of duties. The DRTVBAC model is implemented in the actual system, the figure shows that the task associated with the dynamic management of role and the role assignment is more flexible on authority and recovery, it can be met the principle of least privilege on the role implement of a specific task permission activated; separated the authority from the process of the duties completing in the workflow; prevented sensitive information discovering from concise and dynamic view interface; satisfied with the requirement of the variable task-flow frequently.

  12. Object oriented programming techniques applied to device access and control

    In this paper a model, called the device server model, has been presented for solving the problem of device access and control faced by all control systems. Object Oriented Programming techniques were used to achieve a powerful yet flexible solution. The model provides a solution to the problem which hides device dependancies. It defines a software framework which has to be respected by implementors of device classes - this is very useful for developing groupware. The decision to implement remote access in the root class means that device servers can be easily integrated in a distributed control system. A lot of the advantages and features of the device server model are due to the adoption of OOP techniques. The main conclusion that can be drawn from this paper is that 1. the device access and control problem is adapted to being solved with OOP techniques, 2. OOP techniques offer a distinct advantage over traditional programming techniques for solving the device access problem. (J.P.N.)

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

    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.

  14. Audit-Based Access Control for Electronic Health Records

    Dekker, M.A.C.; Etalle, S.; Gadducci, F.

    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 acce

  15. Audit-Based Access Control for Electronic Health Records

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

    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 acc

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

    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

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

    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.

  18. Access control issues and solutions for large sites

    The Lawrence Livermore National Laboratory (LLNL) operates an automated access control system consisting of more than 100 portals. We have gained considerable practical experience in the issues involved in operating this large system, and have identified the central issues to include system reliability, the large user population, the need for central control, constant change, high visibility and the budget. This paper outlines these issues and draws from our experience to discuss some fruitful ways of addressing them

  19. Access control and interlock system at the Advanced Photon Source

    Forrestal, J.; Hogrefe, R.; Knott, M.; McDowell, W.; Reigle, D.; Solita, L.; Koldenhoven, R.; Haid, D. [Argonne National Lab., IL (United States). Advanced Photon Source

    1997-08-01

    The Advanced Photon Source (APS) consists of a linac, position accumulator ring (PAR), booster synchrotron, storage ring, and up to 70 experimental beamlines. The Access Control and Interlock System (ACIS) utilizes redundant programmable logic controllers (PLCs) and a third hard-wired chain to protect personnel from prompt radiation generated by the linac, PAR, synchrotron, and storage ring. This paper describes the ACIS`s design philosophy, configuration, hardware, functionality, validation requirements, and operational experience.

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

    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.

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

    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.

  2. Protocol for the Control of Emergencies with Dangerous Materials

    This document is required to serve as a guide for plant engineers, in charge of the security and industrial hygiene or those people that for its work, have relationship with the use, storage and distribution of chemical substances, which represent a diversity of risks as the toxicity, the inflammability and the risk of explosion. The information that the specific protocol contains is precise and a series of sections that summarize the general information of the substance are developed, like its use, the risk of explosion, the inflammability and the physical-chemical properties. Additionally, some sections are included like the answer mechanisms before the fire presence, the personnel's decontamination and of the equipment, the gathering of the waste and the procedures of first aids. The chemical substances that cause bigger quantity of events for dangerous materials in Costa Rica are the acids, the bases, the chlorine, the liquate petroleum gas (LPG), the ammonia and the agro-chemicals. Due to the intrinsic risk that it possesses these substances, a protocol to act efficiently in front of an emergency related with some of the substances are developed. Due to the increment in the incidence of events with dangerous materials in different population's sectors, for example spills in the roads, emergencies in industries and educational centers, a law with the purpose of stopping the use and the indiscriminate manipulation of these substances in non-capable locations is necessary. Additionally, it is necessary the upgrade in the equipment and in the containers that don't fulfill the minimum requirements of security, as well as to offer the maximum security to people that have contact with such chemical substances. (Author)

  3. Ubiquitous access control and policy management in personal networks

    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...... distributed master devices acting as access points- and also pure peer-to-peer interactions inside the PN. Taking benefit from the modularity and scalability of the design, this solution can be extended into supporting coalitions of different security domains, deriving from the creation of PNs federations....

  4. Distributed Networked Control System for Power Supply System of the Accelerator Based on Canopen Protocol

    Network based control system for a power supply unit of the linear accelerator was developed. Front-end level of the system is based on CAN fieldbus with CANopen and CANEX application level protocols. Both local and remote control foe each CANopen node is provided. Level 2 control stations of the system are ARM9 CPU based machines, operating under Linux OS

  5. A User Profile Based Access Control Model and Architecture

    Meriem Zerkouk

    2013-02-01

    Full Text Available Personalization and adaptation to the user profile capability are the hottest issues to ensure ambientassisted living and context awareness in nowadays environments. With the growing healthcare andwellbeing context aware applications, modeling security policies becomes an important issue in thedesign of future access control models. This requires rich semantics using ontology modeling for themanagement of services provided to dependant people. However, current access control models remainunsuitable due to lack of personalization, adaptability and smartness to the handicap situation.In this paper, we propose a novel adaptable access control model and its related architecture in whichthe security policy is based on the handicap situation analyzed from the monitoring of user’s behavior inorder to grant a service using any assistive device within intelligent environment. The design of ourmodel is an ontology-learning and evolving security policy for predicting the future actions of dependentpeople. This is reached by reasoning about historical data, contextual data and user behavior accordingto the access rules that are used in the inference engine to provide the right service according to theuser’s needs.

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

    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.

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

    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 Quality control (QC) of the analyses was monitored at three levels: the laboratory performing the analysis, the USGS QC officer, and the principal investigator for the study. This level of review resulted in an average of one QC sample for every 20 field samples, which proved to be minimally adequate for such a large-scale survey. Additional QC samples should be added to monitor within-batch quality to the extent that no more than 10 samples are analyzed between a QC sample. Only Cr (77%), Y (82%), and Sb (80%) fell outside the acceptable limits of accuracy (% recovery between 85 and 115%) because of likely residence in mineral phases resistant to 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

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

    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 3, HClO4, and HF. Separate methods were used for Hg, Se, total C, and carbonate-C on this same size fraction. Only Ag, In, and Te had a large percentage of concentrations below the detection limit. Quality control (QC) of the analyses was monitored at three levels: the laboratory performing the analysis, the USGS QC officer, and the principal investigator for the study. This level of review resulted in an average of one QC sample for every 20 field samples, which proved to be minimally adequate for such a large-scale survey. Additional QC samples should be added to monitor within-batch quality to the extent that no more than 10 samples are analyzed between a QC sample. Only Cr (77%), Y (82%), and Sb (80%) fell outside the acceptable limits of accuracy (% recovery between 85 and 115%) because of likely residence in mineral phases resistant to 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

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

    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...

  10. Verification of the safety communication protocol in train control system using colored Petri net

    This paper deals with formal and simulation-based verification of the safety communication protocol in ETCS (European Train Control System). The safety communication protocol controls the establishment of safety connection between train and trackside. Because of its graphical user interface and modeling flexibility upon the changes in the system conditions, this paper proposes a composition Colored Petri Net (CPN) representation for both the logic and the timed model. The logic of the protocol is proved to be safe by means of state space analysis: the dead markings are correct; there are no dead transitions; being fair. Further analysis results have been obtained using formal and simulation-based verification approach. The timed models for the open transmit system and the application process are created for the purpose of performance analysis of the safety communication protocol. The models describe the procedure of data transmission and processing, and also provide relevant timed and stochastic factors, as well as time delay and lost packet, which may influence the time for establishment of safety connection of the protocol. Time for establishment of safety connection of the protocol in normal state is verified by formal verification, and then time for establishment of safety connection with different probability of lost packet is simulated. After verification it is found that the time for establishment of safety connection of the safety communication protocol satisfies the safety requirements.

  11. A Multiparty Controlled Bidirectional Quantum Secure Direct Communication and Authentication Protocol Based on EPR Pairs

    Chang, Yan; Zhang, Shi-Bin; Yan, Li-Li; Sheng, Zhi-Wei

    2013-06-01

    A multiparty controlled bidirectional quantum secure direct communication and authentication protocol is proposed based on EPR pair and entanglement swapping. The legitimate identities of communicating parties are encoded to Bell states which act as a detection sequence. Secret messages are transmitted by using the classical XOR operation, which serves as a one-time-pad. No photon with secret information transmits in the quantum channel. Compared with the protocols proposed by Wang et al. [Acta Phys. Sin. 56 (2007) 673; Opt. Commun. 266 (2006) 732], the protocol in this study implements bidirectional communication and authentication, which defends most attacks including the ‘man-in-the-middle’ attack efficiently.

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

    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.

  13. On TCP-based Session Initiation Protocol (SIP) Server Overload Control

    Shen, Charles

    2010-01-01

    The Session Initiation Protocol (SIP) server overload management has attracted interest since SIP is being widely deployed in the Next Generation Networks (NGN) as a core signaling protocol. Yet all existing SIP overload control work is focused on SIP-over-UDP, despite the fact that TCP is increasingly seen as the more viable choice of SIP transport. This paper answers the following questions: is the existing TCP flow control capable of handling the SIP overload problem? If not, why and how can we make it work? We provide a comprehensive explanation of the default SIP-over-TCP overload behavior through server instrumentation. We also propose and implement novel but simple overload control algorithms without any kernel or protocol level modification. Experimental evaluation shows that with our mechanism the overload performance improves from its original zero throughput to nearly full capacity. Our work leads to the important general insight that the traditional notion of TCP flow control alone is incapable of...

  14. Type-Based Access Control in Data-Centric Systems

    Caires, Luís; Pérez, Jorge A.; Seco, João Costa; Vieira, Hugo Torres; Ferrão, Lúcio

    Data-centric multi-user systems, such as web applications, require flexible yet fine-grained data security mechanisms. Such mechanisms are usually enforced by a specially crafted security layer, which adds extra complexity and often leads to error prone coding, easily causing severe security breaches. In this paper, we introduce a programming language approach for enforcing access control policies to data in data-centric programs by static typing. Our development is based on the general concept of refinement type, but extended so as to address realistic and challenging scenarios of permission-based data security, in which policies dynamically depend on the database state, and flexible combinations of column- and row-level protection of data are necessary. We state and prove soundness and safety of our type system, stating that well-typed programs never break the declared data access control policies.

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

    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.

  16. An Access Control Model of Virtual Machine Security

    QIN Zhong-yuan; Chen, Qi; Lv, You; Qiang, Yong; GUO Ai-wen; SHEN Ri-sheng; Zhang Qunfang

    2013-01-01

    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 improve...

  17. Integrating CERN e-groups into TWiki access control.

    Jones, PL; Hoymr, N; CERN. Geneva. IT Department

    2010-01-01

    Wikis allow for easy collaborative editing of documents on the web for users located in different buildings, cities or even countries. TWiki culture lends to open free form editing and most pages are world readable and editable by CERN authenticated users, however access control is possible and is used to protect sensitive documents. This note discusses the integration of E-groups for authorisation purposes at CERN.

  18. Achieving Fine-grained Access Control in Virtual Organisations

    Zhang, Nien Fan; Yao, L.; Nenadic, A.; Chin, J.; Goble, C.; Rector, A.; Chadwick, David W; Otenko, Sassa; Shi, Q.

    2007-01-01

    In a virtual organization environment, where services and data are provided and shared amongorganizations from different administrative domains and protected with dissimilar security policies and measures, there is a need for a flexible authentication framework that supports the use of various authentication methods and tokens. The authentication strengths derived from the authentication methods and tokens should be incorporated into an access-control decision-making process, so that more sen...

  19. Access and control of resources: Lessons from the SANREM CRSP

    Flora, Cornelia B.

    2001-01-01

    Metadata only record Developing sustainability in an agricultural ecosystem requires that attention be given to inequities within communities. The experiences of SANREM CRSP revealed that gender inequality was a significant factor in the access and control of resources that were critical for the projects reaching their goals. Among the resources of financial, manufactured, human, environmental, and social capital, enhancing social capital among women was a crucial component of plans for in...

  20. THE ADMINISTRATOR OBJECT PATTERN FOR ROLE-BASED ACCESS CONTROL

    S. R. KODITUWAKKU

    2010-01-01

    The Object-Oriented paradigm approaches the software development by representing real world entities into classes of software objects. Object oriented design patterns facilitate small scale and large scale design reuse. This paper presents an object oriented design pattern, Administrator Object, to address the User-Role assignment problem in Role Based Access Control (RBAC). Two alternative solutions are proposed. The pattern is presented according to the Gang of Four template.

  1. THE ADMINISTRATOR OBJECT PATTERN FOR ROLE-BASED ACCESS CONTROL

    S. R. KODITUWAKKU

    2010-12-01

    Full Text Available The Object-Oriented paradigm approaches the software development by representing real world entities into classes of software objects. Object oriented design patterns facilitate small scale and large scale design reuse. This paper presents an object oriented design pattern, Administrator Object, to address the User-Role assignment problem in Role Based Access Control (RBAC. Two alternative solutions are proposed. The pattern is presented according to the Gang of Four template.

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

    Guoping Zhang; Jing Liu

    2011-01-01

    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 ...

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

    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. PMID:15066555

  4. Material control and surveillance for high frequency access vaults project

    The 'Material Control and Surveillance for High Frequency Access Vaults' project sponsored by United States Department of Energy's Office of Security Policy, Policy Integration and Technical Support Program (SO-20.3) focuses on enhancing nuclear materials control and surveillance in vaults that are frequently accessed. The focus of this effort is to improve materials control and accountability (MC and A) while decreasing the operational impact of these activities. Los Alamos and Y-12 have developed a testbed at the Los Alamos National Laboratory for evaluating and demonstrating integrated technologies for use in enhancing materials control and accountability in active nuclear material storage vaults. An update will be provided on the new systems demonstrated in the test-bed including a 'confirmatory cart' for expediting the performance of inventory and radio-frequency actuated video that demonstrates the concept of automated data entry for materials moving between MBA's. The United States Department of Energy's Office of Security Policy, Policy Integration and Technical Support Program (SO-20.3) has sponsored a project where nuclear material inventory, control and surveillance systems are evaluated, developed, and demonstrated in an effort to provide technologies that reduce risk, increase material assurance, and provide cost-efficient alternatives to manpower-intensive physical inventory and surveillance approaches for working (high-frequency-access) vaults. This Fiscal Year has been largely focused on evaluating and developing components of two sub-systems that could be used either separately in nuclear material vaults or as part of a larger integrated system for nuclear materials accountability, control and surveillance.

  5. ARCPAS - Automatic radiation control point access system an automated data collection terminal for radiation dose and access control

    Nuclear facilities such as nuclear power plants or fuel processing facilities are required to maintain accurate records of personnel access, exposure and work performed. Most facilities today have some sort of computerized data collection system for radiation dose and access control. The great majority rely on handwritten records, i.e., dose card or sign-in sheet which in turn are transferred to a computerized records management system manually. The ARCPAS terminal provides a method for automating personnel exposure data collection and processing. The terminal is a user interactive device which contains a unit for automatically reading and zeroing pocket dosemeters, a security badge reader for personnel identification, a 16 digit key pad for RWP information entry, a high resolution color CRT for interactive communication and a high speed tape printer providing an entry chit. The chit provides the individual worker with a record of the transaction including an individual identifying number, remaining dose for the quarter or period and RWP under which the worker entered the controlled area. The purpose of automating the access control is to provide fast, accurate, realtime data to the records management system. A secondary purpose is to relieve trained health physics technicians of control point duties so that their training and skills can be utilized more effectively in a facility's health physics program

  6. State control, access to capital and firm performance

    Oliver Zhen Li; Xijia Su; Zhifeng Yang

    2012-01-01

    We study the effect of state control on capital allocation and investment in China, where the government screens prospective stock issuers. We find that state firms are more likely to obtain government approval to conduct seasoned equity offerings than non-state firms. Further, non-state firms exhibit greater sensitivities of subsequent investment and stock performance to regulatory decisions on stock issuances than state firms. Our work suggests that state control of capital access distorts resource allocation and impedes the growth of non-state firms. We also provide robust evidence that financial constraints cause underinvestment.

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

    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.

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

    Garbutt Jane M; Highstein Gabrielle; Yan Yan; Strunk Robert C

    2012-01-01

    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 ...

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

    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.

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

    Smith, David B., E-mail: dsmith@usgs.gov [US Geological Survey, Denver Federal Center, MS 973, Denver, CO 80225 (United States); Woodruff, Laurel G. [US Geological Survey, St. Paul, MN 55112 (United States); O' Leary, Richard M. [US Geological Survey, Denver Federal Center, MS 973, Denver, CO 80225 (United States); Cannon, William F. [US Geological Survey, 954 National Center, Reston, VA 20192 (United States); Garrett, Robert G. [Geological Survey of Canada, 601 Booth Street, Ottawa, ON, Canada K1A 0E8 (Canada); Kilburn, James E. [US Geological Survey, Denver Federal Center, MS 973, Denver, CO 80225 (United States); Goldhaber, Martin B. [US Geological Survey, Denver Federal Center, MS 964, Denver, CO 80225 (United States)

    2009-08-15

    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 <2-mm fraction of each sample was analyzed for Al, Ca, Fe, K, Mg, Na, S, Ti, Ag, As, Ba, Be, Bi, Cd, Ce, Co, Cr, Cs, Cu, Ga, In, La, Li, Mn, Mo, Nb, Ni, P, Pb, Rb, Sb, Sc, Sn, Sr, Te, Th, Tl, U, V, W, Y, and Zn by inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry following a near-total digestion in a mixture of HCl, HNO{sub 3}, HClO{sub 4}, and HF. Separate methods were used for Hg, Se, total C, and carbonate-C on this same size fraction. Only Ag, In, and Te had a large percentage of concentrations below the detection limit. Quality control (QC) of the analyses was monitored at three levels: the laboratory performing the analysis, the USGS QC officer, and the principal investigator for the study. This level of review resulted in an average of one QC sample for every 20 field samples, which proved to be minimally adequate for such a large-scale survey. Additional QC samples should be added to monitor within-batch quality to the extent that no more than 10 samples are analyzed between a QC sample. Only Cr (77%), Y (82%), and Sb (80%) fell outside the acceptable limits of accuracy (% recovery between 85 and 115%) because of likely residence in mineral phases resistant to the acid digestion. A separate sample of 0-5-cm material was collected at each site for determination of organic

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

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

    2016-01-01

    , 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......, which comes at the price of increased delay and reduced system throughput. FD is expected to accelerate the TCP congestion control mechanism and hence mitigate such consequences. System level results show that FD can outperform HD and alleviate the TCP drawbacks when the inter-cell interference...

  12. Energy-efficient MAC protocols for Wireless Sensor Networks

    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.

  13. Studying the Noise Control Engineering Protocols in Industry

    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.

  14. A model to reduce complexity and maintain coherence between Access Control and Transmission Control policies

    Bertrand, Yoann; Blay-Fornarino, Mireille; Boudaoud, Karima; Riveill, Michel

    2016-01-01

    In order to protect resources from unauthorized access and data leakage in companies, security experts and administrators can use mechanisms such as Access Control (AC) and Transmission Control (TC). Both AC and TC are based on policies that are defined, modified and revoked by these experts. However, policy management can be a time-consuming and tiresome task, especially when both mechanisms are used on large sets of users and resources. Moreover, contradictions between AC and TC policies ca...

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

    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.

  16. A field exercise course to train IAEA safeguards inspectors in implementing the additional protocol and performing complementary access activities (LA-UR-06-5798)

    Full text: The IAEA Department of Safeguards has the task of implementing the Additional Protocol (AP) in the Member States that have signed agreements bringing that treaty into force. The IAEA inspector under the traditional INFCIRC/153 safeguards has been an accountant focused on the declared nuclear material stores of a Member State. The INFCIRC/540 Strengthened Safeguards System (SSS) provides the Agency and its inspectors with the right to investigate a Member State's nuclear programme to see if all declared activities are in order and no undeclared activities exist. This broadening of the scope of the inspector's responsibilities has changed the training of the inspectors to orient them to being an investigator compared to an accountant. The Safeguards training department has created a curriculum of courses that provides the background to train the inspectorate into this new inspection regime. The United States Support Program (USSP) has contributed to this curriculum by putting together a course at Brookhaven National Laboratory (BNL) in Additional Protocol Complementary Access (APCA) to give the IAEA the opportunity to provide inspectors a necessary field exercise in a realistic environment at a research site. Brookhaven National Laboratory contains three shutdown nuclear research reactors, operating particle accelerators, hot cells, radioactive waste storage, laser laboratories, and magnet production facilities on a large site very similar to numerous research facilities around the world situated in non-nuclear weapon states (NNWS). The BNL team created an Article 2 declaration containing annotated maps of the site, descriptions of the buildings on site, satellite and aerial photographs of the area, and a declaration of research activities on the site. The declaration is as realistic to actual BNL research except that proprietary and security concerns of the BNL site have been taken into account. The BNL team felt the best training vehicle provides a

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

    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...

  18. Minimal Protocol for MRS Quality Control and Acceptance Test for Philips-Achieva MRS Tool

    Nicolosi, Stefania; Zucchetto, Aldo; Vicari, Giuseppe; D’Angelo, Ildebrando; Messana, Domenico; Gilardi, Maria Carla; Scifo, Paola

    2010-01-01

    Difficulties in obtaining good phantoms, improvements in technologies of voxel localization, better sequences for water and fat suppression has brought us to define a minimal Protocol of home-made quality controls of MRS systems. Measurements, defined in the proposed protocol, have, as main goal, to establish if peaks quantification predicts realistic concentration values, meaning that, the occurrence of this event is a sufficient condition to declare that MRS system works good. Moreover, stability measurements helps in a correct data understanding. It is, indeed, realistic to think that environmental condition can introduce casual errors in the working good system. Discrepancies in the working good condition, under stochastic variability (environment), have to be related to systematic errors introduced by the set of pre and/or post-processing operations and/or by any forms of MRS bad-working tool that differs from the previous. The quality control minimal protocol has been executed on a Philips-Achieva MRS s...

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

    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

  20. User Driven Feedback Control System driven using CAN Protocol

    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.

  1. RFID card based access control system with counter for Indus Complex

    As per norms of the Atomic energy regulatory board (AERB) to operate a facility in round the clock which has a potential of radiation exposure, radiation safety rules are to be followed. Indus -1 and Indus-2 are synchrotron radiation sources which are open for various users round the clock. To monitor the persons inside the defined zone at any given time, a system is setup consisting of RF ID cards and their readers along with dedicated software. Software is developed in Visual Basic and uses UDP network protocol for receiving data from readers installed at various locations and connected to local area network. The paper describes the access control scheme followed in Indus Accelerator Complex. (author)

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

    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.

  3. An Access Control Model of Virtual Machine Security

    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.

  4. Privacy and Access Control for IHE-Based Systems

    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.

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

    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. French permanent survey on indoor air quality - Part 1.: Measurement protocols and quality control

    Ramalho, Olivier; Derbez, Mickael; Gregoire, Anthony; Garrigue, Julien; Kirchner, Séverine

    2006-01-01

    This paper focuses on a synthesis of the measurement and analytical protocols from the 2003-2005 campaign of the French permanent survey on indoor air quality and presents the associated quality control system including data traceability, quality code and interlaboratory tests. Preliminary exploitation of measurement and analysis errors are presented

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

    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 trainings focused on the 3 directions of medial, posteromedial, and posterior directions and aimed at exercises increasing fatigue resistance. PMID:27328275

  8. Joint Implementation under the Kyoto Protocol. Together on the road towards a better, controllable environment

    The main questions to be answered in this report concern the control on the compliance of the most important obligations as formulated in the Kyoto Protocol. Also attention is paid to the monitoring and reporting requirements of so-called flexible mechanisms, in particular joint implementation. 29 refs

  9. Analysis of quality control protocol implementation of equipment in radiotherapy services

    Considering the importance of the Quality Assurance in the radiotherapy services, there was an interest to make tests' evaluation for a Quality Control for the cobalt equipment, linear accelerator and simulator as a classification and comparison. The work proposed is a suggestion that can serve as tool for medical physicists that are starting to work in the radiotherapy area and for the most experts. The discussions were made by the gathering of local tests and official protocols, resulting in a minimum protocol as a suggestion for a routine work, emphasizing the periodicity and level of tolerance of each one of the tests. (author)

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

    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

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

    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.

  12. Advent of Biometric Sensors in Field of Access Control

    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.

  13. THE USAGE OF HRU SEGMENT MATRIX ACCESS IN THE ANALYSIS OF INFORMATION SECURITY SYSTEMS WHICH MAKE MANDATORY ACCESS CONTROL

    Korolev I. D.

    2014-09-01

    Full Text Available In this article we consider the usage of HRU access matrix changing system allowing for information security system which makes mandatory access control in case of information security analysis by using an automatic classification of formalized documents in the system of electronic document management

  14. An Improved Contract Net Protocol with Multi-Agent for Reservoir Flood Control Dispatch

    Wei Huang; Xingnan Zhang; Xiaodong Wei

    2011-01-01

    Contract Net Protocol (CNP) has been widely used in solving the problems of multi-Agent cooperates and reservoir flood control optimization dispatch. This paper designs an Agent functional module based on the multi-Agent coordinated the construction of reservoir flood control optimization dispatch and the corresponding Agent to solve the problem of classical CNP in the Agent communication aspect, to enhance the efficiency of reservoir optimization dispatch and to improve the insufficiency of ...

  15. LeCroy & Tektronix Oscilloscopes Remotely Controlled with LABView Drivers on LAN / GPIB Communication Protocol

    PRUTIANU Florin; POPESCU Viorel

    2012-01-01

    This paper presents a method to remote control oscilloscopes from LeCroy and Tektronix manufacturers. These drivers can be built to work for more models than one. As programming/implementation software it is used LabView, version 8.5, developed by National Instruments. These devices are remote controlled via Ethernet communication protocol or GPIB. By building device drivers for these devices, it is offered the possibility to integrate them into measuring or validation systems or other applic...

  16. One Bit Is Enough : a Framework for Deploying Explicit Feedback Congestion Control Protocols

    Vasic, Nedeljko; Kuntimaddi, Srinidhi; Kostic, Dejan

    2009-01-01

    Since the bandwidth-delay products of Internet links keep increasing, issues with TCP's convergence time, throughput, and amount of queuing in these environments are becoming more pressing. As we move toward the next-generation Internet, it is important to start experimenting with congestion control protocols for high BDP networks as soon as possible. Load-factor based congestion control approach holds great promise as it requires moderate changes in routers (only to monitor and inser...

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

    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.

  18. 78 FR 51810 - Twenty-Fourth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    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...

  19. 77 FR 25525 - Thirteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems.

    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...

  20. 77 FR 2343 - Eleventh Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2012-01-17

    ...). 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 a.m.-4..., Airport Security Access Control Systems. The agenda will include the following: February 9, 2012...

  1. On shaky ground - A study of security vulnerabilities in control protocols

    The recent introduction of information technologies such as Ethernet R into nuclear industry control devices has resulted in significantly less isolation from the outside world. This raises the question of whether these systems could be attacked by malware, network hackers or professional criminals to cause disruption to critical operations in a manner similar to the impacts now felt in the business world. To help answer this question, a study was undertaken to test a representative control protocol to determine if it had vulnerabilities that could be exploited. A framework was created in which a test could express a large number of test cases in very compact formal language. This in turn, allowed for the economical automation of both the generation of selectively malformed protocol traffic and the measurement of device under test's (DUT) behavior in response to this traffic. Approximately 5000 protocol conformance tests were run against two major brands of industrial controller. More than 60 categories of errors were discovered, the majority of which were in the form of incorrect error responses to malformed traffic. Several malformed packets however, caused the device to respond or communicate in inappropriate ways. These would be relatively simple for an attacker to inject into a system and could result in the plant operator losing complete view or control of the control device. Based on this relatively small set of devices, we believe that the nuclear industry urgently needs to adopt better security robustness testing of control devices as standard practice. (authors)

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

    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.

  3. The deployment of routing protocols in distributed control plane of SDN.

    Jingjing, Zhou; Di, Cheng; Weiming, Wang; Rong, Jin; Xiaochun, Wu

    2014-01-01

    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. PMID:25250395

  4. Protocol for the quality control systems of electronic portal imaging used in verification of radiotherapy treatment

    Following the approach of quality control of radiotherapy equipment, conceived in the IAEA TECDOC-1151, we analyzed the different tests must be to an EPID to guarantee levels of accuracy required in the administration of radiation treatments, including the study of the impact of different parameters, geometric and dosimetric imaging, involved in the process. Established the types and frequency of checks, as well as procedures for their implementation, the allowable tolerances set of values records and forms for recording . Was carried out assessment protocol in various services based on amorphous silicon EPID for its applicability and scope. Was designed and validated in clinical practice protocol for EPID quality control, demonstrating its applicability with a minimum of material and human resources. It We concluded that with proper and systematic quality control program, tests including dosimetry, the EPID can provide valuable information about physico-beam dosimetry, and ensure adequate accuracy geometric in the patient's location. (author)

  5. Exploring Round Trip Time fairness for Adaptive Layered Transmission Control Protocol

    V.Kavidha

    2010-05-01

    Full Text Available High performance data transfer services is needed in long distance high-speed networks. In this paper Adaptive Layered Transmission Control Protocol (ALTCP is proposed, which is used for making more scalability in highspeed networks. ALTCP is a simple adaptive layering technique for making the Additive Increase Multiplicative Decrease (AIMD algorithms used by TCP more efficient in probing for the available link bandwidth. ALTCP uses a three-dimensional congestion control framework. First the macroscopic control is employed to layer quickly and made efficient by using available link bandwidth, second microscopic control is used for extends the existing AIMD algorithm of TCP to determine the per acknowledgement behavior. Third the intermediate control is employed for decoupling the aggregate throughout from the number of opened TCP flows in parallel. In this research paper ALTCP protocol is designed and analyzed based on ns-2 simulations. The results show that ALTCP has faster magnitude than TCP in utilizing high bandwidth links. ALTCP has better TCP friendliness and Round Trip Time (RTT fairness compared with high-speed protocols namely High-speed TCP and Scalable TCP.

  6. Trust-based Access Control in Virtual Learning Community

    Wang, Shujuan; Liu, Qingtang

    The virtual learning community is an important application pattern of E-Learning. It emphasizes the cooperation of the members in the community, the members would like to share their learning resources, to exchange their experience and complete the study task together. This instructional mode has already been proved as an effective way to improve the quality and efficiency of instruction. At the present time, the virtual learning communities are mostly designed using static access control policy by which the access permission rights are authorized by the super administrator, the super administrator assigns different rights to different roles, but the virtual and social characteristics of virtual learning community make information sharing and collaboration a complex problem, the community realizes its instructional goal only if the members in it believe that others will offer the knowledge they owned and believe the knowledge others offered is well-meaning and worthy. This paper tries to constitute an effective trust mechanism, which could promise favorable interaction and lasting knowledge sharing.

  7. Security Aspects of Distance-Bounding Protocols

    Onete, Maria Cristina

    2012-01-01

    Authentication protocols, run between a so-called prover and a so-called verifier, enable the verifier to decide whether a prover is legitimate or not. Such protocols enable access control, and are used in e.g.~logistics, public transport, or personal identification. An authentication protocol is considered secure if an adversary cannot impersonate a legitimate prover. Such an adversary may eavesdrop authentication attempts between a legitimate prover and a legitimate verifier, interact with ...

  8. A Semantic Context-Based Model for MobileWeb Services Access Control

    Haibo Shen; Yu Cheng

    2011-01-01

    As mobile web services becomes more pervasive, applications based on mobile web services will need flexible access control mechanisms. Unlike traditional approaches based on the identity or role for access control, access decisions for these applications will depend on the combination of the required attributes of users and the contextual information. This paper proposes a semantic context-based access control model (called SCBAC) to be applied in mobile web services environment by combining ...

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

    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...

  10. Variable TDMA MAC Protocol For WDM EPON

    Minsuk; Jung; Yongseok; Chang; Jonghoon; Eom; Sungho; Kim

    2003-01-01

    A MAC(Media Access Control) protocol, one of the most important technologies for an EPON(Ethernet Passive Optical Network), contains a scheduling algorithm to avoid collisions in shared links and assigns an effective bandwidth when ONUs (Optical Network Units) transfer signals upward. The current paper proposes a MAC Protocol that operates a TDMA(Time method with a variable slot assignment to overcome short of bandwidth using by the number of n wavelength., the next generation access network. To verify ...

  11. Access Control in Decentralised Publish/Subscribe Systems

    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.

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

    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.

  13. 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

    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.

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

    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. PMID:23629061

  15. A Self-Configurable Server for Controlling Devices Over the Simple Network Management Protocol

    Rybnikov, V.; Petrosyan, V.

    2015-01-01

    open-source protocol that allows manufacturers toutilize it for controlling and monitoring their hardware.More and more SNMP-manageable devices show up onthe market that can be used by control systems foraccelerators. SNMP devices are also being used at thefree-electron laser (FLASH [1]) and planned to be used atthe European X-ray Free Electron Laser (XFEL[2]) atDESY, Hamburg, Germany. To provide an easy anduniform way of controlling SNMP devices a serverprogram has been developed. The server...

  16. Using Simple Network Management Protocol (SNMP) implementing data flow and run controls in the KLOE experiment

    Event builder systems in high rate physics experiments are going to be configured as computer networks built around switches (FDDI, ATM, FCS, HIPPI). Data coming from different sectors of the apparatus go into the switch in such a way that all the data related to the same event are concentrated in the same processor. A central processor that is responsible of the data flow control manages the assignment between events and processors. The standard TCP/IP is frequently used to transfer data, while the standard SNMP is used to manage the network devices. The KLOE experiment intent to extend the use of the SNMP protocol in its DAQ system. Private extensions of the SNMP standard MIB are used to implement the network related and feed-back functionalities of the data flow protocol. Similar extensions are used to implement the command distribution of the Run Control system. (author)

  17. GMPLS: IP-Centric Control Protocols for Optical Networks(Tutorial)

    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. Protocol for quality control of scanners used in the simulation of radiotherapy treatment planning

    Computed Tomography (CT) has become the tool fundamental imaging of modern radiation therapy, to locate targets and critical organs and dose planning. Tomographs used for these purposes require strict assurance program quality, which differs in many aspects of monitoring required for diagnostic use only with intention. The aim of this work has been the design and validation of a quality control protocol applicable to any TAC used for simulation, radiotherapy planning. (author)

  19. Weight-loss intervention using implementation intentions and mental imagery: a randomised control trial study protocol

    Hattar, Anne; Hagger, Martin S.; Pal, Sebely

    2015-01-01

    Background Overweight and obesity are major health problems worldwide. This protocol describes the HEALTHI (Healthy Eating and Active LifesTyle Health Intervention) Program, a 12-week randomised-controlled weight-loss intervention that adopts two theory-based intervention techniques, mental imagery and implementation intentions, a behaviour-change technique based on planning that have been shown to be effective in promoting health-behaviour change in previous research. The effectiveness of go...

  20. MObile Technology for Improved Family Planning Services (MOTIF): study protocol for a randomised controlled trial.

    Smith, C.; Vannak, U; Sokhey, L; Ngo, TD; Gold, J; Khut, K; Edwards, P.; Rathavy, T; Free, C

    2013-01-01

    BACKGROUND Providing women with contraceptive methods following abortion is important to reduce repeat abortion rates, yet evidence for effective post-abortion family planning interventions are limited. This protocol outlines the evaluation of a mobile phone-based intervention using voice messages to support post-abortion family planning in Cambodia. METHODS/DESIGN A single blind randomised controlled trial of 500 participants. Clients aged 18 or over, attending for abortion at four Mari...

  1. Requirements and Challenges of Location-Based Access Control in Healthcare Emergency Response

    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...... 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...... emergency response scenario which highlights the novel challenges that arise when enforcing access control in an environment with moving subjects and objects. To address a realistic application scenario, we consider movement on road networks, and we identify complex access control decisions relevant to such...

  2. Multi-tag content access control in RFID system

    Xue, Shun

    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...

  3. Physical aspects of quality assurance in radiotherapy: A protocol for quality control

    In consistency with the increasing requests from Member States for establishing radiotherapy programmes, an IAEA Technical Co-operation project was initiated in Latin America aimed at improving the physical aspects (as a complement to the clinical issues) of quality assurance in radiotherapy; this ARCAL XXX project (RLA/6/032) was classified as a Model Project of the IAEA. Among the important outcomes of the project were (i) the training of a considerable number of medical physicists in hospitals of the region, (ii) the development of a protocol for quality control procedures, and (iii) the organization of quality audit site visits (to the participant countries) where the implementation in hospitals of the developed quality control procedures is verified. The present publication is the protocol for quality control of the physical aspects of radiotherapy. It contains detailed procedures on what should be measured by a medical physicist in a radiotherapy treatment unit and related equipment, and how this should be made. The latter is made through several appendices, which make the document rather unique. The protocol was developed by medical physicists of the region for the professionals of the region, and it is the first document of this kind ever written in Spanish. A training course was organized in November 1998 (Havana, Cuba) where its practical implementation was taught. There are plans to have this document translated into different languages for the various regions having similar TC projects. (author)

  4. Energy Efficient MAC Protocols for Wireless Sensor Network: A Survey

    Eleazar Chukwuka

    2013-08-01

    Full Text Available Wireless Sensor Network (WSN is an attractive choice for a variety of applications as no wiredinfrastructure is needed. Other wireless networks are not as energy constrained as WSNs, because theymay be plugged into the mains supply or equipped with batteries that are rechargeable and replaceable.Among others, one of the main sources of energy depletion in WSN is communications controlled by theMedium Access Control (MAC protocols. An extensive survey of energy efficient MAC protocols ispresented in this article. We categorise WSN MAC protocols in the following categories: controlled access(CA, random access (RA, slotted protocols (SP and hybrid protocols (HP. We further discuss howenergy efficient MAC protocols have developed from fixed sleep/wake cycles through adaptive to dynamiccycles, thus becoming more responsive to traffic load variations. Finally we present open researchquestions on MAC layer design for WSNs in terms of energy efficiency.

  5. Cross-layer rate control, medium access control and routing design in cooperative VANET

    Zhou, Liang; Zheng, Baoyu; Geller, Benoit; Wei, Anne; Xu, Shan; Li, Yajun

    2008-01-01

    In this paper, we address the rate control, the Medium Access Control (MAC) and the routing problem for cooperative Vehicular Ad-Hoc Network (VANET) in the framework of cross-layer design. At first, we introduce the cooperative communication conception to VANET, and propose an opportunistic cooperation strategy to improve the system performance. And then, we develop a cross-layer solution which consists of the link capacity detection with adjusting persistence probability at the MAC Layer, th...

  6. Study Application of RADIUS Protocol on Ethernet

    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.

  7. Access Control Mechanisms for Semantic Web services-A Discussion on Requirements & Future Directions

    Gondara, Mandeep Kaur

    2011-01-01

    Semantic Web is an open, distributed, and dynamic environment where access to resources cannot be controlled in a safe manner unless the access decision takes into account during discovery of web services. Security becomes the crucial factor for the adoption of the semantic based web services. An access control means that the users must fulfill certain conditions in order to gain access over web services. Access control is important in both perspectives i.e. legal and security point of view. This paper discusses important requirements for effective access control in semantic web services which have been extracted from the literature surveyed. I have also discussed open research issues in this context, focusing on access control policies and models in this paper.

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

    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.

  9. Road and street smart lighting control systems as a new application area of the hot-potato protocol

    Kiedrowski, Piotr; Gutierrez Lopez, Jose Manuel; Boniewicz, Piotr; Perez de Prado, Rocio

    2014-01-01

    This paper presents the new application area of the hot-potato routing protocol, which is a “last-mile” communication network for controlling systems of road and street lighting. Four variants of the hot-potato protocol are analyzed with use of the graph theory. For the assessment of the traffic ...

  10. Real-Time Performance of Hybrid Mobile Robot Control Utilizing USB Protocol

    Jacek Augustyn

    2015-01-01

    This article discusses the problem of usability of the USB 2.0 protocol in the area of real-time control of a mobile robot. Optimization methods of data transfer handling were proposed. The impact of the optimization results on the entire system’s performance was examined in practice. As a test-bed, a hybrid system composed of two devices communicating by direct USB connection was implemented. The first of the mentioned devices was a 32-bit SoC micro-system serving as a direct control unit, a...

  11. Priority Based Congestion Control Dynamic Clustering Protocol in Mobile Wireless Sensor Networks.

    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. PMID:26504898

  12. How to Improve the Accessibility and Reduce the Total Cost of Ownership with Ecolig Protocol and Android in Mobile Learning

    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.

  13. Implementing the Kyoto protocol in Europe: Interactions between international and Community controls

    This bibliographical note presents a book which discusses the coexistence of the Kyoto protocol and of a regional regime within the European Union for the actual application of rules requiring mechanisms of control. The international regime implements a continuous monitoring which combines conventional techniques and more intrusive procedures. The European Community introduced a non-contentious mechanism with a large and strong law basis and sanction ability. The author assesses the ability of the monitoring system as a whole to ensure the very credibility of the Protocol. She also assesses the reliability of international and community economic tools which aim at reducing greenhouse gas emissions at a minimum cost. She also discusses the desirable evolutions of the regime of struggle against climate changes

  14. Research of Real-Time Wireless Networks Control System MAC Protocol

    Xiao-ying Shuai

    2010-04-01

    Full Text Available Data transported through the control system of WLAN included: burst real-time data (BRD, periodical real-time date (PRD and non-real-time data (NRD. Priority ranged from the high level to the low level and distinguished them by different inter frame space (IFS. BRD station sent RTS to reserve channel freeing SIFS and transmitted burst data after SIFS; PRD transported through AP polling; non-real-time data transport through CSMA/CA protocol at the stage of DCF. This paper presented the new solution(limited and polling backoff, LPB to solve the conflict, set conflict threshold, adopted modified backoff algorithm of burst real-time data, improved the performance of real-time data and guaranteed the delay to keep the delay limited. The analysis and simulation show that the new protocol can promote the response of real-time data and make the delay limited.

  15. Collaboration Policies: Access Control Management in Decentralized Heterogeneous Workflows

    Mine Altunay

    2006-07-01

    Full Text Available Service-oriented computing promotes collaboration by defining the standards layer that allows compatibility between disparate domains. Workflows, by taking advantage of the service oriented framework, provide the necessary tools to harness services in order to tackle complicated problems. As a result, a service is no longer exposed to a small pre-determined homogeneous pool of users; instead it has a large, undefined, and heterogeneous pool of users. This paradigm shift in computing results in increased service exposure. The interactions among the services of a workflow must be carefully evaluated against the security risks associated with them. Classical security problems, such as delegation of rights, conflict of interest, and access control in general, become more complicated due to multiple autonomous security domains and the absence of pre- established trust relationships among the domains. Our work tackles these problems in two aspects: it provides a service owner with the necessary means to express and evaluate its trust requirements from a workflow (collaboration policies, and it incorporates these trust requirements into the workflow-planning framework (workflow authorization framework. Our policy-based framework allows bilateral peer-level trust evaluations that are based on each peer’s collaboration policies, and incorporates the outcome of these evaluations into the workflow planning logic. As a result, our work provides the necessary tools for promoting multi-party ad-hoc collaborations, and aims to reduce the reluctance and hesitation towards these collaborations by attacking the security risks associated with them.

  16. Enhanced Role Based Access Control Mechanism for Electronic Examination System

    Adebukola Onashoga

    2014-02-01

    Full Text Available Over the years, e-learning and e-examination has become standard in many institutions of higher learning. It has been observed that examination questions and results can be easily intercepted by invalid users, thus the security of resources shared among valid users is not guaranteed. In order to solve these problems as it relates to access control, a Role based Examination System (RBES was designed, developed and evaluated. RBES attempted to solve the security issue by the combination of two authentication techniques: text-based authentication and graphical password authentication. The Text-based authentication utilizes two text-based parameters namely the username and password. The graphical password authentication makes use of a finite set of controls (RBES chooses radio buttons which are identified by numbers. These numbers constitute the password used for graphical authentication. To improve on resource sharing among users in the examination system, RBES proposes role management (role creation, role update, role removal and user management (user creation, user update and user removal. The developed system made use of asp.net, C#, IIS server, WAMP server, Mysql and other tools for its development. RBES was tested by some legitimate and illegitimate users and the performance of the system was found to be satisfactory, hence RBES shows an efficient and reliable scheme that can be deployed in any examination or e-learning system. Finally the potential threats to the system were modeled and the use of weak passwords was found to be the most likely threat the system could be vulnerable to.

  17. HIERARCHICAL ACCESS CONTROL IN DYNAMIC PEER GROUPS USING SYMMETRIC POLYNOMIAL AND TREE BASED GROUP ELLIPTIC CURVE DIFFIE HELLMAN SCHEME

    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.

  18. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    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.

  19. A 4D-Role Based Access Control Model for Multitenancy Cloud Platform

    Jiangfeng Li; Zhenyu Liao; Chenxi Zhang; Yang Shi

    2016-01-01

    Since more and more applications and services have been transferred from servers in the B/S architecture to cloud, user access control has become a significant part in a multitenancy cloud platform. Role based access control model makes users participate in an enterprise system as particular identities. However, in a multitenancy cloud environment, it has a high probability that the information of tenants has been leaked by using existing role based access control (RBAC) model. Moreover, mana...

  20. Multi-Trust_OrBAC: Access Control Model for Multi-Organizational Critical Systems Migrated To the Cloud

    Mustapha Ben Saidi.

    2013-05-01

    Full Text Available Security of information systems is a problem chronic, the arrival of cloud computing as a new computing model, feeds the difficulty of implementing effective solutions. Thus more research is currently focused on data security in the cloud, and especially the issue of confidentiality. In this paper we propose a new protocol access control for complex, heterogeneous, interoperable, and distributed systems in the context of Cloud Computing : « Multi-TrustOrBAC » (Multi-Organization - Trust Based Access Control. This protocol allows a TTP «Trust Tierd Party [10] » to force users belonging to several organizations to cooperate to meet the security policies defined independently by them. The aim is to offer to organizations working together and having decided to migrate to the cloud, a means of real-time monitoring of their safety. Our solution is based on both the concept of trust assigned to users and to the definition of an order on the set of security policies. The logical formalism is used to specify and describe the rules of the security policies of different organizations.

  1. Underwater acoustic sensor networks: Medium access control, routing and reliable transfer

    Xie, Peng

    Recently there have been growing interests in monitoring aquatic environments for scientific exploration, commercial exploitation and coastline protection. The ideal vehicle for this type of extensive monitoring is a mobile underwater sensor network (M-UWSN), consisting of a large number of low cost underwater sensors that can move with water currents and dispersion. M-UWSNs are significantly different from terrestrial sensor networks: (1) Radio channels do not work well under water. They must be replaced by acoustic channels, which feature long propagation delays, low communication bandwidth and high channel error rates; (2) While most ground sensors are static, underwater sensor nodes may move with water currents (and other underwater activities), as introduces passive sensor mobility. Due to the very different environment properties and the unique characteristics of acoustic channels, the protocols developed for terrestrial sensor networks are not applicable to M-UWSNs, and new research at every level of the protocol suite is demanded. In this dissertation work, we investigate three fundamental networking problems in M-UWSN design: medium access control, multi-hop routing and reliable data transfer. (1) Medium access control (MAC): the long propagation delays and narrow communication bandwidth of acoustic channels pose the major challenges to the energy-efficient MAC design in M-UWSNs. For the first time, we formally investigate the random access and RTS/CTS techniques in networks with long propagation delays and low communication bandwidth (as in M-UWSNs). Based on this study, we propose a novel reservation-based MAC approach, called R-MAC, for dense underwater sensor networks with unevenly distributed (spatially and temporally) traffic. Simulation results show that R-MAC is not only energy efficient but also supports fairness. (2) Multi-hop routing: In M-UWSNs, energy efficiency and mobility handling are the two major concerns for multi-hop routing, which have

  2. EVCP: a convergence time improved high-speed transport congestion control protocol

    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.

  3. Role-based access control through on-demand classification of electronic health record.

    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. PMID:26559071

  4. Designing a Secure E-commerce with Credential Purpose-based Access Control

    Norjihan Abdul Ghani; Harihodin Selamat; Zailani Mohamed Sidek

    2014-01-01

    The rapid growth of e-commerce has created a great opportunities for both businesses and end users. The essential e-commerce process is required for the successful operation and management of e-commerce activities. One of the processes is access control and security. E-commerce must establish a secure access between the parties in an e-commerce transaction by authenticating users, authorizing access, and enforcing security features. The e-commerce application must authorize access to only tho...

  5. Task-and-role-based access-control model for computational grid

    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.

  6. Wi-Fi Networks Security and Accessing Control

    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.

  7. A Stream Control Transmission Protocol Based OAM System of 3G Cellular Network

    2005-01-01

    OAM (Operations, Administration and Maintenance) system is a very important component of 3G cellular network. In order to acquire overall management, fast response and steady operation, an SCTP (Stream Control Transmission Protocol) based OAM, i. e. , SOAM system was proposed. SOAM implements new characters of SCTP such as multi-stream, enforced SACK and heartbeat mechanism on its transport layer. These characters help SOAM decrease the message transmission delay and accelerate the link failure detection. Besides, a new component named SOAM agent was introduced to improve the operation efficiency of SOAM. The experimental results prove the proposed SOAM system achieves better performance on signaling transmission compared with conventional TCP based OAM system.

  8. Perioperative Glycemic Control in Plastic Surgery: Review and Discussion of an Institutional Protocol.

    Dortch, John D; Eck, Dustin L; Ladlie, Beth; TerKonda, Sarvam P

    2016-07-01

    Perioperative hyperglycemia is a well-known risk factor for surgical morbidity such as wound healing, infection, and prolonged hospitalization. This association has been reported for a number of surgical subspecialties, including plastic surgery. Specialty-specific guidelines have become increasingly available in the literature. Currently, glucose management guidelines for plastic surgery are lacking. Recognizing that multiple approaches exist for perioperative glucose, protocol-based models provide the necessary structure and guidance for approaching glycemic control. In this article, we review the influence of diabetes on outcomes in plastic surgery patients and propose a practical approach to perioperative blood glucose management based on current Endocrine Society and Mayo Clinic institutional guidelines. PMID:27301370

  9. The "Healthy Habits, Healthy Girls" randomized controlled trial for girls: study design, protocol, and baseline results.

    Leme, Ana Carolina Barco; Philippi, Sonia Tucunduva

    2015-07-01

    The purpose of this article is to describe the study design, protocol, and baseline results of the "Healthy Habits, Healthy Girls" program. The intervention is being evaluated through a randomized controlled trial in 10 public schools in the city of São Paulo, Brazil. Data on the following variables were collected and assessed at baseline and will be reevaluated at 7 and 12 months: body mass index, waist circumference, dietary intake, nutrition, physical activity, social cognitive mediators, physical activity level, sedentary behaviors, self-rated physical status, and overall self-esteem. According to the baseline results, 32.4% and 23.4% of girls were overweight in the intervention and control groups, respectively, and in both groups a higher percentage failed to meet daily recommendations for moderate and vigorous physical activity and maximum screen time (TV, computer, mobile devices). There were no significant differences between the groups for most of the variables, except age (p = 0.000) and waist circumference (p = 0.014). The study showed a gap in the Brazilian literature on protocols for randomized controlled trials to prevent obesity among youth. The current study may thus be an important initial contribution to the field. PMID:26248094

  10. APPLICATION OF NEWTON RAPHSON ALGORITHM FOR OPTIMIZING TRANSMISSION CONTROL PROTOCOL PERFORMANCE

    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

    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. Authenticated Blind Issuing of Symmetric Keys for Mobile Access Control System without Trusted Parties

    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. A Generic Role Based Access Control Model for Wind Power Systems

    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....

  14. An effective access control approach to support mobility in IPv6 networks

    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.

  15. "hCG priming" effect in controlled ovarian stimulation through a long protocol

    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. On the Decidability of the Safety Problem for Access Control Policies

    Kleiner, Eldar; Newcomb, Tom

    2006-01-01

    An access control system regulates the rights of users to gain access to resources in accordance with a specified policy. The rules in this policy may interact in a way that is not obvious via human inspection; there is, therefore, a need for automated verification techniques that can check whether a policy does indeed implement some desired security requirement. Thirty years ago, a formalisation of access control presented a model and a safety specification for which satisfaction is undecida...

  17. Random access procedures and radio access network (RAN) overload control in standard and advanced long-term evolution (LTE and LTE-A) networks

    Kiilerich Pratas, Nuno; Thomsen, Henning; Popovski, Petar

    2015-01-01

    In this chapter, we describe and discuss the current LTE random access procedure and the Radio Access Network Load Control solution within LTE/LTE-A. We provide an overview of the several considered load control solutions and give a detailed description of the standardized Extended Access Class...... Barring solution. We then provide a brief overview of the Load Control solutions provided by the Enhanced Packet Core (EPC) Network and how they intertwine with the Extended Access Barring at the Enhanced Universal Terrestrial Radio Access Network (E-UTRAN). We also provide an outlook on the current 3GPP...... efforts in regards to MTC related load control issues....

  18. 单兵作战系统中信息监听冲突消除技术研究%Conflict-Eliminated Channel Access of MAC Protocol in IISCS

    杨令兴; 张喜斌; 魏小龙; 马二涛; 冯文斌

    2013-01-01

    The static slot allocation TDMA channel access algorithms used in Integrated Individual Soldier Combat System ( IISCS ) are not adaptable to the demand of large battlefield network and autonomous operation.To solve the problem,we proposed a dynamic slot allocation TDMA access algorithm of MAC protocol,named C-TDMA,based on consumption algorithm and binary tree slot allocation algorithm .The access conflicts are eliminated in the control slot by multiple RTS/CTS.The consumption arithmetic is used to control the data flow and improve fairness access of different services on the basis of delay quality,and the binary tree slot allocation algorithm is used for distributed network environment .The simulation results indicate that real-time services can be supported by C-TDMA protocol in heavy-load and mixed-service in IISCS,which presents good performance on access efficiency .%针对当前单兵作战系统通信网络中所采用的固定分配TDMA算法不能适应大型战场环境和自组织运行需求的问题,提出一种基于消费算法和二叉树时隙分配算法的动态时隙分配TDMA算法,即C-TDMA算法,通过多组载波监听消除接入冲突,在保证延时的基础上使用消费算法控制节点分组发送量,提高信道接入公平性,同时通过二叉树时隙分配算法支持网络分布式运行。仿真结果表明,对于负载较重、传输混合业务且时延敏感的单兵作战系统网络,该算法可以消除接入冲突,提高信道吞吐率。

  19. H-RBAC: A Hierarchical Access Control Model for SaaS Systems

    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.

  20. 77 FR 71474 - Seventeenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2012-11-30

    ...). 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, 2012... Federal Aviation Administration Seventeenth Meeting: RTCA Special Committee 224, Airport Security...

  1. 78 FR 43963 - Twenty-Third Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2013-07-22

    ...). 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, 2013... Federal Aviation Administration Twenty-Third Meeting: RTCA Special Committee 224, Airport Security...

  2. 77 FR 64838 - Sixteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2012-10-23

    ...). 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, 2012... Federal Aviation Administration Sixteenth Meeting: RTCA Special Committee 224, Airport Security...

  3. 78 FR 16757 - Twentieth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2013-03-18

    ...). 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 9... Federal Aviation Administration Twentieth Meeting: RTCA Special Committee 224, Airport Security...

  4. 78 FR 31627 - Twenty-Second Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2013-05-24

    ...). 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, 2013... Federal Aviation Administration Twenty-Second Meeting: RTCA Special Committee 224, Airport Security...

  5. 78 FR 7850 - Nineteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2013-02-04

    ...). 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, 2013... Federal Aviation Administration Nineteenth Meeting: RTCA Special Committee 224, Airport Security...

  6. 77 FR 55894 - Fifteenth Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2012-09-11

    ...). 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, 2012... Federal Aviation Administration Fifteenth Meeting: RTCA Special Committee 224, Airport Security...

  7. Keep on Blockin’ in the Free World: Personal Access Control for Low-Cost RFID Tags

    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

  8. 78 FR 22025 - Twenty First Meeting: RTCA Special Committee 224, Airport Security Access Control Systems

    2013-04-12

    ...). 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, 2013... Federal Aviation Administration Twenty First Meeting: RTCA Special Committee 224, Airport Security...

  9. 75 FR 4007 - Risk Management Controls for Brokers or Dealers With Market Access

    2010-01-26

    ... COMMISSION 17 CFR Part 240 RIN 3235-AK53 Risk Management Controls for Brokers or Dealers With Market Access... market access to customers or other persons, to implement risk management controls and supervisory.... 40354 (August 24, 1998), 63 FR 46264 (August 31, 1998) (NASD NTM-98-66). Certain market participants...

  10. 76 FR 60398 - Exemption to Prohibition on Circumvention of Copyright Protection Systems for Access Control...

    2011-09-29

    ... Prohibition on Circumvention of Copyright Protection Systems for Access Control Technologies, 68 FR 62011... Circumvention of Copyright Protection Systems for Access Control Technologies, 71 FR 68472, 68480, published in... Rulemaking Proceeding The Digital Millennium Copyright Act, Public Law 105-304 (1998), amended title 17...

  11. Medium access control and hardware prototype designs for low-energy wireless sensor networks

    Kohvakka, M.

    2009-07-01

    A Wireless Sensor Network (WSN) is an emerging technology consisting of small, cheap, and ultra-low energy sensor nodes, which cooperatively monitor physical quantities, actuate, and perform data processing tasks. A deployment may comprise thousands of randomly distributed autonomous nodes, which must self-configure and create a multi-hop network topology.This thesis focuses on low-energy WSNs targeting to long network lifetime. The main research problem is the combination of adaptive and scalable multi-hop networking with constrained energy budget, processing power, and communication bandwidth. The research problem is approached by energy-efficient protocols and low-power sensor node platforms. The main contribution of this thesis is an energy-efficient Medium Access Control (MAC) design for TUTWSN (Tampere University of Technology Wireless Sensor Network). The design comprises channel access and networking mechanisms, which specify data exchange, link synchronization, network self-configuration, and neighbor discovery operations. The second outcome are several low-power sensor node platforms, which have been designed and implemented to evaluate the performance of the MAC design and hardware components in real deployments. The third outcome are the performance models and analysis of several MAC designs including TUTWSN, IEEE 802.15.4, and the most essential research proposals.The results and conclusion of this Thesis indicate that it is possible to implement multi-hop WSNs in harsh and dynamic operation conditions with years of lifetime using current low-cost components and batteries. Energy analysis results indicate that the lowest energy consumption is achieved by using simple and high data-rate transceivers. It is also critical to minimize sleep mode power consumption of all components and to use accurate wake-up timers. However, the selection of components constitutes only a minor part of the solution, and an energy-efficient MAC layer design being able to

  12. PANATIKI: A Network Access Control Implementation Based on PANA for IoT Devices

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

    2013-01-01

    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 a...

  13. Security Mechanisms and Access Control Infrastructure for Biometrics Passport using Cryptographic Protocols

    V.K. NARENDIRA KUMAR; B. Srinivasan

    2013-01-01

    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...

  14. Security Mechanisms and Access Control Infrastructure for Biometrics Passport using Cryptographic Protocols

    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.

  15. Design and analysis of medium access control protocols for ad hoc and cooperative wireless networks

    Alonso Zárate, Jesús

    2009-01-01

    La presente tesis doctoral contribuye a la incesante evolución de las comunicaciones inalámbricas. Se centra en el diseño de protocolos de acceso al medio (MAC) para redes ad hoc y redes inalámbricas cooperativas. En una primera parte introductoria se presenta un minucioso estado del arte y se establecen las bases teóricas de las contribuciones presentadas en la tesis. En esta primera parte introductoria se definen las principales motivaciones de la tesis y se plantean los objetivos. Despu...

  16. Physical aspects of radiotherapy quality assurance: quality control protocol - Update of IAEA TECDOC-1151

    An International Atomic Energy Agency (IAEA) regional project for Latin America (ARCAL XXX) entitled ''Improvement of Quality Assurance in Radiotherapy'' was completed in 2000. One of its more relevant contributions was the development of a quality control protocol for radiotherapy physics, published as an IAEA TECDOC. This was the first document of this type published entirely in Spanish, having a marked practical approach, and focused on the situation of the radiotherapy in Latin America at that time. The document found broad application and was widely adopted in the region. The recommendations and guidelines of the document were also applied in other countries having a similar level of development in radiotherapy. Since the publication of TECDOC-1151, the status of radiotherapy has changed significantly in many of the radiotherapy institutions in the Latin American region. Technological advances and improvements have created the need for a thorough revision of the protocol to reflect the current situation regarding radiotherapy equipment and techniques, keeping it a suitable and practical tool to guarantee high quality in the nowadays rather complex radiotherapy treatments. To fulfill this goal, a specific task was included in the IAEA regional project ''Improvements in Quality Assurance in Radiotherapy in the Latin American Region'' (ARCAL XC), running during the period 2007-2009, where a group of experts was formed and commissioned with the document revision. The general criteria and procedures given in TECDOC-1151 are still valid for basic radiotherapy equipment, widely disseminated and playing an important role in clinical practice in the region. It was then considered to develop additional criteria and recommendations for the new advanced technologies in the form of a supplement to the existing protocol. The supplement describes procedures and provides recommendations for newly introduced radiotherapy equipment, followed by a series of appendixes where

  17. Implementation of the quality control protocol in Crawls; Puesta en marcha del protocolo de control de calidad en rastreos

    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)

  18. A dynamic access control method based on QoS requirement

    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.

  19. The Study of Access Control for Service-Oriented Computing in Internet of Things

    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.

  20. A Secure Time-Stamp Based Concurrency Control Protocol For Distributed Databases

    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.

  1. An Access Control Metamodel for Web Service-Oriented Architecture

    Emig, Christian; Brandt, Frank; Abeck, Sebastian; Biermann, Jürgen; Klarl, Heiko

    2008-01-01

    With the mutual consent to use WSDL (Web Service Description Language) to describe web service interfaces and SOAP as the basic communication protocol, the cornerstone for web service-oriented architecture (WSOA) has been established. Considering the momentum observable by the growing number of specifications in the web service domain for the indispensable cross-cutting concern of identity management (IdM) it is still an open issue how a WSOA-aware IdM architecture is built and how it is link...

  2. Sustainable medium access control: Implementation and evaluation of ODMAC

    Fafoutis, Xenofon; Di Mauro, Alessio; Dragoni, Nicola

    vital to guarantee the sustainability of the system; whereas, in the opposite case, the system should use the energy surplus to increase the application performance. In this paper, we implement and evaluate On-Demand MAC (ODMAC), the first receiver-initiated MAC protocol specifically designed for energy...... harvesting applications. In particular, we provide a basic yet fully operational implementation of ODMAC for the Texas Instruments' MSP430 microprocessor family. Furthermore, we verify the theoretical results of our previous work by achieving sustainable operation of an energy harvesting node in various...

  3. Monitoring of high voltage supply using the Controller Area Network protocol

    Luz, Igo Amauri dos S.; Farias, Paulo Cesar M.A.; Guedes, Germano P. [Universidade Estadual de Feira de Santana (UEFS), BA (Brazil)

    2011-07-01

    Full text: In recent years, experimental physics has made great progress in the investigation of the phenomenology of neutrinos, with significant contribution from experiments using nuclear reactors as source of particles. In this context, The Neutrinos Angra Project proposes the use of an anti-neutrinos detector with ability to monitor parameters related to the activity of nuclear reactors. One of the tasks defined in the project is the development of a system to control and to monitor the high voltage supply units used by the photomultiplier tubes (PMTs) of the detector. The solution proposed in this work is based on the use of microcontrollers, from Microchip PIC family to adjust the operating point of the high voltage supply units and to acquire the current and output voltage data. Analysis of these data allows the effective control of the gain of the PMTs and to identify anomalous operational conditions. In this work is proposed the study of the Controller Area Network (CAN) protocol and the implementation of a laboratory network to reproduce the typical operations of data acquisition and information transfer between the nodes. The development of this network is divided in two stages. The first part consisted of the setup of a CAN network, using the PIC18F2680 microcontroller, which has the CAN protocol internally implemented. This network serves as a reduced model of the final system, allowing simulation of typical situations of data acquisition and transmission between the nodes and a computer. In the second part of the work, the PIC18F4550 microcontroller was associated with the external CAN controller MCP2515 to develop a CAN/USB converter. This converter provides a new communication channel between network nodes and the computer, in addition to the RS232 interface. (author)

  4. Multi-channel MAC Protocol in Cognitive Radio Networks

    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.

  5. Risk access control model for Hadoop%面向Hadoop的风险访问控制模型

    李甲帅; 彭长根; 朱义杰; 马海峰

    2016-01-01

    Traditional access control models are hard to restrain the malicious behavior of authorized users. Accord-ingly, Hadoop platform with this access control model is difficult to prevent the risk of privacy disclosure. A model of access control based on risk was proposed. A risk function of information entropy was designed from users’ his-torical behavior based on setting the tags of subject and object. Furthermore, the tracking chain of risk was built, which could adjust the users’ access authority dynamically according to the risk value and its volatility. Combining with access token and risk supervision, the risk access control mechanism for big data privacy protection was real-ized, which could be applied to enhance the security of Hadoop Kerberos protocol. Finally, the experiment result shows that the model can constrain the authorized users’ access behavior effectively.%传统的访问控制机制难以约束授权用户的恶意行为,使得采用这种访问控制机制的Hadoop平台面临着大数据隐私泄露的风险。提出了一种基于风险的访问控制模型,该模型通过对主体和客体标签的设定,根据用户的历史行为记录构造信息熵风险值计算函数,并进一步建立风险值波动的追踪链,通过风险值及其波动幅度动态调整用户的访问权限。将该模型应用于Hadoop的Kerberos认证协议的改进,结合访问令牌及风险监测实现大数据隐私保护风险访问控制机制。最后,针对医疗大数据进行应用仿真,实验表明该模型可以有效约束大数据应用平台中授权用户的访问行为。

  6. Description of the Protocols for Randomized Controlled Trials on Cancer Drugs Conducted in Spain (1999–2003)

    Bonfill, Xavier; Ballesteros, Mónica; Gich, Ignasi; Serrano, María Antonia; García López, Fernando; Urrútia, Gerard

    2013-01-01

    Objective To describe the characteristics of randomized controlled clinical trials (RCT) on cancer drugs conducted in Spain between 1999 and 2003 based on their protocols. Methods We conducted an observational retrospective cohort study to identify the protocols of RCTs on cancer drugs authorized by the Agencia Española del Medicamento y Productos Sanitarios (AEMPS) (Spanish Agency for Medicines and Medical Devices) during 1999-2003. A descriptive analysis was completed and the association be...

  7. Role mining in business taming role-based access control administration

    Colantonio, Alessandro; Ocello, Alberto

    2012-01-01

    With continuous growth in the number of information objects and the users that can access these objects, ensuring that access is compliant with company policies has become a big challenge. Role-based Access Control (RBAC) - a policy-neutral access control model that serves as a bridge between academia and industry - is probably the most suitable security model for commercial applications. Interestingly, role design determines RBAC's cost. When there are hundreds or thousands of users within an organization, with individual functions and responsibilities to be accurately reflected in terms of a

  8. Characterization of accessibility for affine connection control systems at some points with nonzero velocity

    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.

  9. Exploring the impact of a decision support intervention on vascular access decisions in chronic hemodialysis patients: study protocol

    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

  10. A Fault-Tolerant Emergency-Aware Access Control Scheme for Cyber-Physical Systems

    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.

  11. A General Attribute and Rule Based Role-Based Access Control Model

    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.

  12. Enhancing Security and Privacy in Video Surveillance through Role-Oriented Access Control Mechanism

    Mahmood Rajpoot, Qasim

    Use of video surveillance has significantly increased in the last few decades. Modern video surveillance systems are equipped with techniques that automatically extract information about the objects and events from the video streams and allow traversal of data in an effective and efficient manner...... that is suitable for video surveillance systems as well as other domains sharing similar requirements. As the currently dominant access control models – the role-based access control (RBAC) and the attribute-based access control (ABAC) – suffer from limitations while offering features complementary to each other......, their integration has become an important area of research. Our access control model combines the two models in a novel way in order to unify their benefits while avoiding their limitations. Our approach provides a mechanism that not only takes information about the current circumstances into account during access...

  13. An entity access control model for network services management

    Dias, Bruno

    2005-01-01

    The Network Services Management Framework tries to overcome the most important limitations of present network management frameworks, namely the most widely supported framework – the Internet Network Management Framework – by defining a management framework using a network services management distributed architecture that provides services management functions with any desired level of functionality. This document introduces one of the most important parts of this framework, the Entity Access ...

  14. Workflow management systems, their security and access control mechanisms

    Chehrazi, Golriz

    2007-01-01

    This paper gives an overview of workflow management systems (WfMSs) and their security requirements with focus on access mechanisms. It is a descriptive paper in which we examine the state of the art of workflow systems, describe what security risks affect WfMSs in particular, and how these can be diminiuished. WfMSs manage, illustrate and support business processes. They contribute to the performance, automation and optimization of processes, which is important in the global economy today. ...

  15. A View-Based Access Control Model for SPARQL

    Gabillon, Alban; Letouzey, Léo

    2010-01-01

    Existing security models for RDF use RDF patterns for defining the security policy. This approach leads to a number of security rules which rapidly tends to be unmanageable. In this paper we define a new security model which follows the traditional approach of creating security views, which has long been used by SQL database administrators. Our model first logically distributes RDF data into SPARQL views and then it defines security rules regulating SPARQL access to views. Moreover our model ...

  16. Proximity-based access control for context-sensitive information provision in SOA-based systems

    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.

  17. Cooperative MIMO Transmissions in WSN Using Threshold Based MAC Protocol

    Vidhya, J.; Dananjayan, P.

    2010-01-01

    Sensor networks require robust and efficient communication protocols to maximise the network lifetime.Radio irregularity, channel fading and interference results in larger energy consumption and latency forpacket transmission over wireless channel. Cooperative multi-input multi-output (MIMO) schemes whenincorporated in wireless senor network (WSN) can significantly improve the communicationperformance. An inefficiently designed medium access control (MAC) protocol however, may diminishthe per...

  18. MULTI - TRACER CONTROL ROOM AIR INLEAKAGE PROTOCOL AND SIMULATED PRIMARY AND EXTENDED MULTI - ZONE RESULTS

    The perfluorocarbon tracer (PFT) technology can be applied simultaneously to the wide range in zonal flowrates (from tens of cfms in some Control Rooms to almost 1,000,000 cfm in Turbine Buildings), to achieve the necessary uniform tagging for subsequent determination of the desired air inleakage and outleakage from all zones surrounding a plant's Control Room (CR). New types of PFT sources (Mega sources) were devised and tested to handle the unusually large flowrates in a number of HVAC zones in power stations. A review of the plans of a particular nuclear power plant and subsequent simulations of the tagging and sampling results confirm that the technology can provide the necessary concentration measurement data to allow the important ventilation pathways involving the Control Room and its air flow communications with all adjacent zones to be quantitatively determined with minimal uncertainty. Depending on need, a simple single or 3-zone scheme (involving the Control Room alone or along with the Aux. Bldg. and Turbine Bldg.) or a more complex test involving up to 7 zones simultaneously can be accommodated with the current revisions to the technology; to test all the possible flow pathways, several different combinations of up to 7 zones would need to be run. The potential exists that for an appropriate investment, in about 2 years, it would be possible to completely evaluate an entire power plant in a single extended multizone test with up to 12 to 13 separate HVAC zones. With multiple samplers in the Control Room near each of the contiguous zones, not only will the prevalent inleakage or outleakage zones be documented, but the particular location of the pathway's room of ingress can be identified. The suggested protocol is to perform a 3-zone test involving the Control Room, Aux. Bldg., and Turbine Bldg. to (1) verify CR total inleakage and (2) proportion that inleakage to distinguish that from the other 2 major buildings and any remaining untagged locations

  19. Increasing walking in patients with intermittent claudication: Protocol for a randomised controlled trial

    O'Carroll Ronan E

    2010-10-01

    Full Text Available Abstract Background People with intermittent claudication are at increased risk of death from heart attack and stroke compared to matched controls. Surgery for intermittent claudication is for symptom management and does not reduce the risk of cardiovascular morbidity and mortality. Increasing physical activity can reduce claudication symptoms and may improve cardiovascular health. This paper presents the pilot study protocol for a randomised controlled trial to test whether a brief psychological intervention leads to increased physical activity, improvement in quality of life, and a reduction in the demand for surgery, for patients with intermittent claudication. Methods/Design We aim to recruit 60 patients newly diagnosed with intermittent claudication, who will be randomised into two groups. The control group will receive usual care, and the treatment group will receive usual care and a brief 2-session psychological intervention to modify illness and walking beliefs and develop a walking action plan. The primary outcome will be walking, measured by pedometer. Secondary outcomes will include quality of life and uptake of surgery for symptom management. Participants will be followed up after (a 4 months, (b 1 year and (c 2 years. Discussion This study will assess the acceptability and efficacy of a brief psychological intervention to increase walking in patients with intermittent claudication, both in terms of the initiation, and maintenance of behaviour change. This is a pilot study, and the results will inform the design of a larger multi-centre trial. Trial Registration Current Controlled Trials ISRCTN28051878

  20. Multi-agent controlled teleportation of multi-qubit quantum information via two-step protocol

    Yang Jie

    2005-01-01

    Utilizing both the general quantum teleportation and the two-step protocol, a new method is presented by which multi-qubit quantum information can be teleported in a much easier way from a sender Alice to a receiver Bob via the control of many agents in a network than by Yang et al's method. In this method, only all the agents collaborate with Bob can the unknown states in Alice's qubits be fully reconstructed in Bob's qubits. Comparisons between the method and Yang et al's method are made. Results show that, in this method, the preparation difficulty of initial states and the identification difficulty of entangled states are considerably reduced, new method is more feasible in technique, and Hadamard operations are not needed at all.

  1. Anonymous authentication protocol for multi-services in wireless environments

    2008-01-01

    To provide mutual authentication among users, wireless networks, and service providers in roaming wireless environments, this article presents an anonymous authentication and access control protocol. Bases on this protocol, entities of different trusted domains can mutually authenticate each other and preserve the anonymity of users. Hybrid cryptosystem, secret splitting, and hash chains are used in the protocol, which decrease computational loads and establish trusted relations for both entities. The proposed protocol has the least computation complexity compared with other protocols, whereas, the security has been significantly improved.

  2. Immediate vs. delayed insertion of intrauterine contraception after second trimester abortion: study protocol for a randomized controlled trial

    Soon Judith A

    2011-06-01

    Full Text Available Abstract Background We describe the rationale and protocol for a randomized controlled trial (RCT to assess whether intrauterine contraception placed immediately after a second trimester abortion will result in fewer pregnancies than current recommended practice of intended placement at 4 weeks post-abortion. Decision analysis suggests the novel strategy could substantially reduce subsequent unintended pregnancies and abortions. This paper highlights considerations of design, implementation and evaluation of a trial expected to provide rigorous evidence for appropriate insertion timing and health economics of intrauterine contraception after second trimester abortion. Methods/Design Consenting women choosing to use intrauterine contraception after abortion for a pregnancy of 12 to 24 weeks will be randomized to insertion timing groups either immediately (experimental intervention or four weeks (recommended care post abortion. Primary outcome measure is pregnancy rate at one year. Secondary outcomes include: cumulative pregnancy rates over five year follow-up period, comprehensive health economic analyses comparing immediate and delayed insertion groups, and device retention rates, complication rates (infection, expulsion and, contraceptive method satisfaction. Web-based Contraception Satisfaction Questionnaires, clinical records and British Columbia linked health databases will be used to assess primary and secondary outcomes. Enrolment at all clinics in the province performing second trimester abortions began in May 2010 and is expected to complete in late 2011. Data on one year outcomes will be available for analysis in 2014. Discussion The RCT design combined with access to clinical records at all provincial abortion clinics, and to information in provincial single-payer linked administrative health databases, birth registry and hospital records, offers a unique opportunity to evaluate such an approach by determining pregnancy rate at one

  3. Assessment of current practices in creating and using passwords as a control mechanism for information access

    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.

  4. A Distributed Architecture for Sharing Ecological Data Sets with Access and Usage Control Guarantees

    Bonnet, Philippe; Gonzalez, Javier; Granados, Joel Andres

    2014-01-01

    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...... 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...... 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....

  5. Craniosacral therapy for migraine: Protocol development for an exploratory controlled clinical trial

    Coeytaux Remy R

    2008-06-01

    have withdrawn from the study after giving consent. Conclusion This report endorses the feasibility of undertaking a rigorous randomized clinical trial of CST for migraine using a standardized CST protocol and an innovative control protocol developed for the study. Subjects are able and willing to complete detailed headache diaries during an 8-week baseline period, with few dropouts during the study period, indicating the acceptability of both interventions. Trial Registration ClinicalTrials.gov NCT00665236

  6. A Semantic Context-Based Model for MobileWeb Services Access Control

    Haibo Shen

    2011-02-01

    Full Text Available As mobile web services becomes more pervasive, applications based on mobile web services will need flexible access control mechanisms. Unlike traditional approaches based on the identity or role for access control, access decisions for these applications will depend on the combination of the required attributes of users and the contextual information. This paper proposes a semantic context-based access control model (called SCBAC to be applied in mobile web services environment by combining semantic web technologies with context-based access control mechanism. The proposed model is a context-centric access control solutions, context is the first-class principle that explicitly guides both policy specification and enforcement process. In order to handle context information in the model, this paper proposes a context ontology to represent contextual information and employ it in the inference engine. As well as, this paper specifies access control policies as rules over ontologies representing the concepts introduced in the SCBAC model, and uses semantic web rule language (SWRL to form policy rule and infer those rules by JESS inference engine. The proposed model can also be applied to context-aware applications.

  7. WWW--Wealth, Weariness or Waste. Controlled Vocabulary and Thesauri in Support of Online Information Access.

    Batty, David

    1998-01-01

    Discusses the problems of access to information in a machine-sensible environment, and the potential of modern library techniques to help in solving them. Explains how authors and publishers can make information more accessible by providing indexing information that uses controlled vocabulary, terms from a thesaurus, or other linguistic assistance…

  8. Real-Time Performance of Hybrid Mobile Robot Control Utilizing USB Protocol

    Jacek Augustyn

    2015-02-01

    Full Text Available This article discusses the problem of usability of the USB 2.0 protocol in the area of real-time control of a mobile robot. Optimization methods of data transfer handling were proposed. The impact of the optimization results on the entire system’s performance was examined in practice. As a test-bed, a hybrid system composed of two devices communicating by direct USB connection was implemented. The first of the mentioned devices was a 32-bit SoC micro-system serving as a direct control unit, and the second one was an off-the-shelf PDA providing supervisory control and logging. Due to this design, the system meets regimes of the real-time constraints and maintains continuity of a data stream at a large bandwidth. The real-time performances of subsystems and the entire system were experimentally examined depending on various operating conditions. Thanks to the performed experiments, the dependency of real-time limits on operational parameters has been determined.

  9. Peer mentorship to promote effective pain management in adolescents: study protocol for a randomised controlled trial

    Hayes Loran P

    2011-05-01

    Full Text Available Abstract Background This protocol is for a study of a new program to improve outcomes in children suffering from chronic pain disorders, such as fibromyalgia, recurrent headache, or recurrent abdominal pain. Although teaching active pain self-management skills through cognitive-behavioral therapy (CBT or a complementary program such as hypnotherapy or yoga has been shown to improve pain and functioning, children with low expectations of skill-building programs may lack motivation to comply with therapists' recommendations. This study will develop and test a new manualized peer-mentorship program which will provide modeling and reinforcement by peers to other adolescents with chronic pain (the mentored participants. The mentorship program will encourage mentored participants to engage in therapies that promote the learning of pain self-management skills and to support the mentored participants' practice of these skills. The study will examine the feasibility of this intervention for both mentors and mentored participants, and will assess the preliminary effectiveness of this program on mentored participants' pain and functional disability. Methods This protocol will recruit adolescents ages 12-17 with chronic pain and randomly assign them to either peer mentorship or a treatment-as-usual control group. Mentored participants will be matched with peer mentors of similar age (ages 14-18 who have actively participated in various treatment modalities through the UCLA Pediatric Pain Program and have learned to function successfully with a chronic pain disorder. The mentors will present information to mentored participants in a supervised and monitored telephone interaction for 2 months to encourage participation in skill-building programs. The control group will receive usual care but without the mentorship intervention. Mentored and control subjects' pain and functioning will be assessed at 2 months (end of intervention for mentored participants and

  10. The development of the cell cryopreservation protocol with controlled rate thawing.

    Gurina, Tatyana M; Pakhomov, Alexandr V; Polyakova, Anna L; Legach, Evgeniy I; Bozhok, Galyna A

    2016-06-01

    Thawing in the water bath is often considered as a standard procedure. The thermal history of samples thawed in this way is poorly controlled, but cryopreservation and banking of cell-based products require standardization, automation and safety of all the technological stages including thawing. The programmable freezers allow implementation of the controlled cooling as well as the controlled thawing. As the cell damage occurs during the phase transformation that takes place in the cryoprotectant medium in the process of freezing-thawing, the choice of warming rates within the temperature intervals of transformations is very important. The goal of the study was to investigate the influence of warming rates within the intervals of the phase transformations in the DMSO-based cryoprotectant medium on the cell recovery and to develop a cryopreservation protocol with controlled cooling and warming rates. The temperature intervals of phase transformations such as melting of the eutectic mixture of the cryoprotectant solution (MEMCS), melting of the eutectic salt solution (MESS), melting of the main ice mass (MMIM), recrystallization before MEMCS, recrystallization before MESS and recrystallization before MMIM were determined by thermo-mechanical analysis. The biological experiments were performed on the rat testicular interstitial cells (TIC). The highest levels of the cell recovery and metabolic activity after cryopreservation were obtained using the protocol with the high (20 °C/min) warming rate in the temperature intervals of crystallization of the eutectics as well as recrystallizations and the low (1 °C/min) warming rate in the temperature intervals of melting of the eutectics as well as MMIM. The total cell recovery was 65.3 ± 2.1 %, the recovery of the 3-beta-HSD-positive (Leydig) cells was 82.9 ± 1.8 %, the MTT staining was 32.5 ± 0.9 % versus 42.1 ± 1.7 %; 57.4 ± 2.1 % and 24.0 ± 1.1 % respectively, when compared to the thawing in

  11. Energy harvesting aware hybrid MAC protocol for WBANs

    Ibarra, Ernesto; Antonopoulos, Angelos; KARTSAKLI, Elli; Verikoukis, Christos

    2013-01-01

    In this paper, we propose a hybrid polling Medium Access Control (MAC) protocol with Human Energy Harvesting capabilities, called HEH-BMAC, designed for Wireless Body Area Networks (WBANs). The proposed protocol uses a dynamic schedule algorithm to combine User Identification polling (ID) and Probabilistic Contention (PC) random access, adapting the network operation to the random, time-varying nature of the human energy harvesting sources. HEH-BMAC offers different levels of node priorities ...

  12. State system of accounting for and control of nuclear materials and Protocol Additional in the Slovak Republic

    proposed procedures at the facility for nuclear materials accountancy and control with special reference to material balance areas and key measurement points, measurements of flow and procedures for physical inventory taking. This document is prepared by the IAEA using the Design Information Questionnaire supplied by the facility operator. The Nuclear Regulatory Authority of the Slovak Republic uses computerised system for SSAC - Code ZARUKY 3.00. This code should be able to communicate with the database of operators, which are allowed to handle nuclear material and it should reflect all limitations specified in theirs permissions. It is created on a system with fully satisfactory safety, strictly defined confidentiality and in a system, which allows the access of several users in parallel. As a new component of the code the system for reporting in accordance with the requirements of the Additional Protocol will be incorporated. Starting after political changes in the Central Europe in the beginning of nineties the Slovak Republic is facing a new type of crime illicit trafficking of nuclear and radioactive materials. Direct economical losses in this case are not comparable with the impact on proliferation and radiation safety risk. The government of the Slovak Republic is aware of the situation and has prepared some measures, which may help us to cope with this problem. These measures were mostly concentrated on detection on the state border as well as inside the state. However, the most important is a state system of measures how to prevent removal of material into illegal use. The Protocol Additional was signed by the government of the Slovak Republic in September 1999. However, The Protocol cannot be ratified, as the laws now in effect in the Slovak Republic do not make it possible to meet all requirements resulting from the Protocol. To enable the ratification of the Protocol Additional, first of all it is necessary to amend the Atomic Law and associated regulations

  13. The Smart Card concept applied to access control

    Passwords tend to be handled carelessly, and so are easily lost or stolen. Because they are intangible, their loss or theft generally goes unnoticed. Because they are constant, they may be used by anyone for as long as they remain in active use by a legitimate user. A step up in password security is offered by a new range of products which generate a new code each time the device is used. Devices are being produced in packages as small as a standard plastic credit card, including internal battery power, integral keyboard and LCD display. Security features of the Smart Card are reviewed, and several random access code generators currently available in the commercial marketplace are described

  14. Increasing organ donation via anticipated regret (INORDAR: protocol for a randomised controlled trial

    O'Carroll Ronan E

    2012-03-01

    Full Text Available Abstract Background Throughout the world there is an insufficient supply of donor organs to meet the demand for organ transplantations. This paper presents a protocol for a randomised controlled trial, testing whether a simple, theory-based anticipated regret manipulation leads to a significant increase in posthumous organ donor registrations. Methods We will use a between-groups, prospective randomised controlled design. A random sample of 14,520 members of the adult Scottish general public will be contacted via post. These participants will be randomly allocated into 1 of the 4 conditions. The no questionnaire control (NQC group will simply receive a letter and donor registration form. The questionnaire control (QC arm will receive a questionnaire measuring their emotions and non-cognitive affective attitudes towards organ donation. The theory of planned behavior (TPB group will complete the emotions and affective attitudes questionnaire plus additional items assessing their cognitive attitudes towards organ donation, perceived control over registration and how they think significant others view this action. Finally, the anticipated regret (AR group will complete the same indices as the TPB group, plus two additional anticipated regret items. These items will assess the extent to which the participant anticipates regret for not registering as an organ donor in the near future. The outcome variable will be NHS Blood and Transplant verified registrations as an organ donor within 6 months of receiving our postal intervention. Discussion This study will assess whether simply asking people to reflect on the extent to which they may anticipate regret for not registering as an organ donor increases organ donor registration 6 months later. If successful, this simple and easy to administer theory-based intervention has the potential to save lives and money for the NHS by reducing the number of people receiving treatments such as dialysis. This

  15. Purpose engineering for Contextual Role-Based Access Control (C-RBAC

    Muhammad Nabeel Tahir

    2008-09-01

    Full Text Available Distributed and ubiquitous computing environments have brought enormous efficiency to the collection, manipulation and distribution of information and services. Although this efficiency has revolutionized countless organizations but it has also increased the threats to individual’s privacy because the information stored within the collection of heterogeneous distributed components is sensitive and requires some form of access control. The way to protect privacy in this age of information technology requires such access control system that can accommodate organization requirements to protect privacy of individuals with ease in management and administration of resources. Among those requirements, purpose inference is one of the major problems as the total access control decision mainly relies on the user intentions/purposed. This work in this paper is an attempt to provide purpose engineering semantics that we use for the proposed contextual role-based access control model (C-RBAC in order to comply with HIPAA.

  16. Human engineering considerations in designing a computerized controlled access security system

    This paper describes a human engineering effort in the design of a major security system upgrade at Lawrence Livermore National Laboratory. This upgrade was to be accomplished by replacing obsolete and difficult-to-man (i.e., multiple operator task actions required) security equipment and systems with a new, automated, computer-based access control system. The initial task was to assist the electronic and mechanical engineering staff in designing a computerized security access system too functionally and ergonomically accommodate 100% of the Laboratory user population. The new computerized access system was intended to control entry into sensitive exclusion areas by requiring personnel to use an entry booth-based system and/or a remote access control panel system. The primary user interface with the system was through a control panel containing a magnetic card reader, function buttons, LCD display, and push-button keypad

  17. Modelling and Analysing Access Control Policies in XACML 3.0

    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...... (c.f. GM03,Mos05,Ris13) and manual analysis of the overall effect and consequences of a large XACML policy set is a very daunting and time-consuming task. In this thesis we address the problem of understanding the semantics of access control policy language XACML, in particular XACML version 3.0. The...... main focus of this thesis is modelling and analysing access control policies in XACML 3.0. There are two main contributions in this thesis. First, we study and formalise XACML 3.0, in particular the Policy Decision Point (PDP). The concrete syntax of XACML is based on the XML format, while its standard...

  18. Comparison of CSMA based MAC protocols of wireless sensor networks

    singh, Himanshu

    2012-01-01

    Energy conservation has been an important area of interest in Wireless Sensor networks (WSNs). Medium Access Control (MAC) protocols play an important role in energy conservation. In this paper, we describe CSMA based MAC protocols for WSN and analyze the simulation results of these protocols. We implemented S-MAC, T-MAC, B-MAC, B-MAC+, X-MAC, DMAC and Wise-MAC in TOSSIM, a simulator which unlike other simulators simulates the same code running on real hardware. Previous surveys mainly focused on the classification of MAC protocols according to the techniques being used or problem dealt with and presented a theoretical evaluation of protocols. This paper presents the comparative study of CSMA based protocols for WSNs, showing which MAC protocol is suitable in a particular environment and supports the arguments with the simulation results. The comparative study can be used to find the best suited MAC protocol for wireless sensor networks in different environments.

  19. The RFID smart card management application for the hotel access control

    Kreslin, Robert

    2011-01-01

    In this thesis we wanted to present the project that was made for a smaller hotel in Nova Gorica. The goal was to create an application for managing access control according to customer's wishes as well as to introduce the system into the existent infrastructure. The first step was to define what access control actually means. In broad terms it is divided into RFID – radio-frequency identification and biometric identification. Both have their strengths and their weaknesses. Next step was choo...

  20. ConXsense - Automated Context Classification for Context-Aware Access Control

    Miettinen, Markus; Heuser, Stephan; Kronz, Wiebke; Sadeghi, Ahmad-Reza; Asokan, N.

    2013-01-01

    We present ConXsense, the first framework for context-aware access control on mobile devices based on context classification. Previous context-aware access control systems often require users to laboriously specify detailed policies or they rely on pre-defined policies not adequately reflecting the true preferences of users. We present the design and implementation of a context-aware framework that uses a probabilistic approach to overcome these deficiencies. The framework utilizes context se...