WorldWideScience

Sample records for on-demand routing protocol

  1. A Multicast Protocol Utilizing On-demand Routing Strategy for MPRN

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper proposes a multicast protocol utilizing ondemand routing strategy for mobile packet radio network. It does not maintain permanent route tables with full topological views. Instead, multicast senders apply on-demand procedures to dynamically discover routes and build forwarding group in this protocol. The data packets are propagated by each forwarding group member via scoped flooding, so the protocol can reduce network bandwidth overhead and avoid the propagation of potentially large routing updates throughout the network.

  2. Performance Analysis of On-Demand Routing Protocols in Wireless Mesh Networks

    Directory of Open Access Journals (Sweden)

    Arafatur RAHMAN

    2009-01-01

    Full Text Available Wireless Mesh Networks (WMNs have recently gained a lot of popularity due to their rapid deployment and instant communication capabilities. WMNs are dynamically self-organizing, self-configuring and self-healing with the nodes in the network automatically establishing an adiej hoc network and preserving the mesh connectivity. Designing a routing protocol for WMNs requires several aspects to consider, such as wireless networks, fixed applications, mobile applications, scalability, better performance metrics, efficient routing within infrastructure, load balancing, throughput enhancement, interference, robustness etc. To support communication, various routing protocols are designed for various networks (e.g. ad hoc, sensor, wired etc.. However, all these protocols are not suitable for WMNs, because of the architectural differences among the networks. In this paper, a detailed simulation based performance study and analysis is performed on the reactive routing protocols to verify the suitability of these protocols over such kind of networks. Ad Hoc On-Demand Distance Vector (AODV, Dynamic Source Routing (DSR and Dynamic MANET On-demand (DYMO routing protocol are considered as the representative of reactive routing protocols. The performance differentials are investigated using varying traffic load and number of source. Based on the simulation results, how the performance of each protocol can be improved is also recommended.

  3. Receiver-Based Ad Hoc On Demand Multipath Routing Protocol for Mobile Ad Hoc Networks.

    Science.gov (United States)

    Al-Nahari, Abdulaziz; Mohamad, Mohd Murtadha

    2016-01-01

    Decreasing the route rediscovery time process in reactive routing protocols is challenging in mobile ad hoc networks. Links between nodes are continuously established and broken because of the characteristics of the network. Finding multiple routes to increase the reliability is also important but requires a fast update, especially in high traffic load and high mobility where paths can be broken as well. The sender node keeps re-establishing path discovery to find new paths, which makes for long time delay. In this paper we propose an improved multipath routing protocol, called Receiver-based ad hoc on demand multipath routing protocol (RB-AOMDV), which takes advantage of the reliability of the state of the art ad hoc on demand multipath distance vector (AOMDV) protocol with less re-established discovery time. The receiver node assumes the role of discovering paths when finding data packets that have not been received after a period of time. Simulation results show the delay and delivery ratio performances are improved compared with AOMDV.

  4. Enhancing On-Demand Multicast Routing Protocols using Mobility Prediction in Mobile Ad-hoc Network

    Directory of Open Access Journals (Sweden)

    Nermin Makhlouf

    2014-08-01

    Full Text Available A Mobile Ad hoc Network (MANET is a self-organizing wireless communication network in which mobile devices are based on no infrastructure like base stations or access points. Minimal configuration and quick deployment make ad hoc networks suitable for emergency situations like disaster recovery or military conflict. Since node mobility may cause links to be broken frequently, a very important issue for routing in MANETs is how to set reliable paths which can last as long as possible. To solve this problem, non-random behaviors for the mobility patterns that mobile users exhibit are exploited. This paper introduces a scheme to improve On-Demand Multicast Routing Protocol (ODMRP performances by using mobility prediction. 

  5. A Time-Slotted On-Demand Routing Protocol for Mobile Ad Hoc Unmanned Vehicle Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hope Forsmann; Robert Hiromoto; John Svoboda

    2007-04-01

    The popularity of UAVs has increased dramatically because of their successful deployment in military operations, their ability to preserve human life, and the continual improvements in wireless communication that serves to increase their capabilities. We believe the usefulness of UAVs would be dramatically increased if formation flight were added to the list of capabilities. Currently, sustained formation flight with a cluster of UAVs has only been achieved with two nodes by the Multi-UAV Testbed at the Massachusetts Institute of Technology. (Park, 2004) Formation flight is a complex operation requiring the ability to adjust the flight patterns on the fly and correct for wind gusts, terrain, and differences in node equipment. All of which increases the amount of inner node communication. Since one of the problems with MANET communication is network congestion, we believe a first step towards formation flight can be made through improved inner node communication. We have investigated current communication routing protocols and developed an altered hybrid routing protocol in order to provide communication with less network congestion.

  6. MQARR-AODV: A NOVEL MULTIPATH QOS AWARE RELIABLE REVERSE ON-DEMAND DISTANCE VECTOR ROUTING PROTOCOL FOR MOBILE AD-HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    K.G. Santhiya

    2012-12-01

    Full Text Available MANET (Mobile Ad-hoc Network is an infra structure less wireless ad-hoc network that does not require any basic central control. The topology of the network changes drastically due to very fast mobility of nodes. So an adaptive routing protocol is needed for routing in MANET. AODV (Ad-hoc On-demand Distance Vector routing is the effective and prominent on-demand Ad-hoc routing protocols. During route establishment phase in traditional AODV, only one route reply message will be sent in the reverse path to establish routing path. The high mobility of nodes may affect the reply messages which lead to the retransmission of route request message by the sender which in turn leads to higher communication delay, power consumption and the reduction in the ratio of packets delivered. Sending multiple route reply messages and establishing multiple paths in a single path discovery will reduce the routing overhead involved in maintaining the connection between source and destination nodes. Multipath routing can render high scalability, end-to-end throughput and provide load balancing in MANET. The new proposed novel Multipath QoS aware reliable routing protocol establishes two routes of maximum node disjoint paths and the data transfer is carried out in the two paths simultaneously. To select best paths, the new proposed protocol uses three parameters Link Eminence, MAC overhead and node residual energy. The experimental values prove that the MQARR-AODV protocol achieves high reliability, stability, low latency and outperforms AODV by the less energy consumption, overhead and delay.

  7. Ad Hoc on-Demand Distance Vector (AODV Routing Protocol Performance Evaluation on Hybrid Ad Hoc Network: Comparison of Result of Ns-2 Simulation and Implementation on Testbed using PDA

    Directory of Open Access Journals (Sweden)

    Riri Sari

    2010-10-01

    Full Text Available In Mobile Ad hoc NETwork (MANET, node supplemented with wireless equipment has the capacity to manage and organise autonomously, without the presence of network infrastructures. Hybrid ad hoc network, enable several nodes to move freely (mobile to create instant communication. Independent from infrastructure. They could access the Local Area Network (LAN or the Internet. Functionalities of ad hoc network very much dependent on the routing protocol that determines the routing around node. Ad hoc On-demand Distance Vector (AODV is one of routing protocols in ad hoc network which has a reactive characteristic. This protocol is the most common protocol being researched and used. In this Research, AODV protocol investigation was conducted by developing a testbed using Personal Computer, several Laptops (the Linux Red Hat operation system 9.0 and Fedora Core 2, and Personal Digital Assistant (PDA. This research also made a complete package by mean of cross compilation for PDA iPAQ. In general, results obtained from the simulation of AODV protocol using Network Simulator NS-2 are packet delivery ratio 99.89%, end-to-end delay of 0.14 seconds and routing overhead of 1,756.61 byte per second. Afterwards results from simulation were compared to results from testbed. Results obtained from testbed are as follows: the packet delivery ratio is 99.57%, the end-to-end delay is 1.004 seconds and the routing overhead is 1,360.36 byte per second.

  8. Mobility-Assisted on-Demand Routing Algorithm for MANETs in the Presence of Location Errors

    Directory of Open Access Journals (Sweden)

    Trung Kien Vu

    2014-01-01

    Full Text Available We propose a mobility-assisted on-demand routing algorithm for mobile ad hoc networks in the presence of location errors. Location awareness enables mobile nodes to predict their mobility and enhances routing performance by estimating link duration and selecting reliable routes. However, measured locations intrinsically include errors in measurement. Such errors degrade mobility prediction and have been ignored in previous work. To mitigate the impact of location errors on routing, we propose an on-demand routing algorithm taking into account location errors. To that end, we adopt the Kalman filter to estimate accurate locations and consider route confidence in discovering routes. Via simulations, we compare our algorithm and previous algorithms in various environments. Our proposed mobility prediction is robust to the location errors.

  9. Improvement In MAODV Protocol Using Location Based Routing Protocol

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    Kaur Sharnjeet

    2016-01-01

    Full Text Available Energy saving is difficult in wireless sensor network (WSN due to limited resources. Each node in WSN is constrained by their limited battery power for their energy. The energy is reduced as the time goes off due to the packet transmission and reception. Energy management techniques are necessary to minimize the total power consumption of all the nodes in the network in order to maximize its life span. Our proposed protocol Location based routing (LBR aimed to find a path which utilizes the minimum energy to transmit the packets between the source and the destination. The required energy for the transmission and reception of data is evaluated in MATLAB. LBR is implemented on Multicast Ad hoc On Demand Distance Vector Routing Protocol (MAODV to manage the energy consumption in the transmission and reception of data. Simulation results of LBR show the energy consumption has been reduced.

  10. Energy Reduction Multipath Routing Protocol for MANET Using Recoil Technique

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Sahu

    2018-04-01

    Full Text Available In Mobile Ad-hoc networks (MANET, power conservation and utilization is an acute problem and has received significant attention from academics and industry in recent years. Nodes in MANET function on battery power, which is a rare and limited energy resource. Hence, its conservation and utilization should be done judiciously for the effective functioning of the network. In this paper, a novel protocol namely Energy Reduction Multipath Routing Protocol for MANET using Recoil Technique (AOMDV-ER is proposed, which conserves the energy along with optimal network lifetime, routing overhead, packet delivery ratio and throughput. It performs better than any other AODV based algorithms, as in AOMDV-ER the nodes transmit packets to their destination smartly by using a varying recoil off time technique based on their geographical location. This concept reduces the number of transmissions, which results in the improvement of network lifetime. In addition, the local level route maintenance reduces the additional routing overhead. Lastly, the prediction based link lifetime of each node is estimated which helps in reducing the packet loss in the network. This protocol has three subparts: an optimal route discovery algorithm amalgamation with the residual energy and distance mechanism; a coordinated recoiled nodes algorithm which eliminates the number of transmissions in order to reduces the data redundancy, traffic redundant, routing overhead, end to end delay and enhance the network lifetime; and a last link reckoning and route maintenance algorithm to improve the packet delivery ratio and link stability in the network. The experimental results show that the AOMDV-ER protocol save at least 16% energy consumption, 12% reduction in routing overhead, significant achievement in network lifetime and packet delivery ratio than Ad hoc on demand multipath distance vector routing protocol (AOMDV, Ad hoc on demand multipath distance vector routing protocol life

  11. VANET Routing Protocols: Pros and Cons

    OpenAIRE

    Paul, Bijan; Ibrahim, Md.; Bikas, Md. Abu Naser

    2012-01-01

    VANET (Vehicular Ad-hoc Network) is a new technology which has taken enormous attention in the recent years. Due to rapid topology changing and frequent disconnection makes it difficult to design an efficient routing protocol for routing data among vehicles, called V2V or vehicle to vehicle communication and vehicle to road side infrastructure, called V2I. The existing routing protocols for VANET are not efficient to meet every traffic scenarios. Thus design of an efficient routing protocol h...

  12. Predictive routing for autonomous mobility-on-demand systems with ride-sharing

    NARCIS (Netherlands)

    Alonso Mora, J.; Wallar, Alex; Rus, Daniela; Bicchi, A.; Maciejewski, T.

    2017-01-01

    Ride-sharing, or carpooling, systems with autonomous vehicles will provide efficient and reliable urban mobility on demand. In this work we present a method for dynamic vehicle routing that leverages historical data to improve the performance of a network of self-driving taxis. In particular, we

  13. On-Demand Routing in Multi-hop Wireless Mobile Ad Hoc Networks

    National Research Council Canada - National Science Library

    Maltz, David A

    2001-01-01

    .... Routing protocols used in ad hoc networks must automatically adjust to environments that can vary between the extremes of high mobility with low bandwidth, and low mobility with high bandwidth...

  14. Generalized routing protocols for multihop relay networks

    KAUST Repository

    Khan, Fahd Ahmed

    2011-07-01

    Performance of multihop cooperative networks depends on the routing protocols employed. In this paper we propose the last-n-hop selection protocol, the dual path protocol, the forward-backward last-n-hop selection protocol and the forward-backward dual path protocol for the routing of data through multihop relay networks. The average symbol error probability performance of the schemes is analysed by simulations. It is shown that close to optimal performance can be achieved by using the last-n-hop selection protocol and its forward-backward variant. Furthermore we also compute the complexity of the protocols in terms of number of channel state information required and the number of comparisons required for routing the signal through the network. © 2011 IEEE.

  15. Achieving sink node anonymity in tactical wireless sensor networks using a reactive routing protocol

    Science.gov (United States)

    2017-06-01

    node anonymity, base station anonymity, Wireless Sensor Networks (WSN), Mobile Ad hoc Network (MANET), Lightweight Ad hoc On-Demand – Next Generation ... Generation (LOADng) reactive-routing protocol to achieve anonymity. This modified protocol prevents an attacker from identifying the sink node without...within the constraints of WSN communication protocols, specifically IEEE 802.15.4. We use and modify the Lightweight Ad hoc On-Demand – Next Generation

  16. A SURVEY ON MULTICAST ROUTING PROTOCOLS FOR PERFORMANCE EVALUATION IN WIRELESS SENSOR NETWORK

    Directory of Open Access Journals (Sweden)

    A. Suruliandi

    2015-03-01

    Full Text Available Multicast is a process used to transfer same message to multiple receivers at the same time. This paper presents the simulation and analysis of the performance of six different multicast routing protocols for Wireless Sensor Network (WSN. They are On Demand Multicast Routing Protocol (ODMRP, Protocol for Unified Multicasting through Announcement (PUMA, Multicast Adhoc On demand Distance Vector Protocol (MAODV, Overlay Boruvka-based Adhoc Multicast Protocol (OBAMP, Application Layer Multicast Algorithm (ALMA and enhanced version of ALMA (ALMA-H for WSN. Among them, ODMRP, MAODV and PUMA are reactive protocols while OBAMP, ALMA and ALMA-H are proactive protocols. This paper compares the performance of these protocols with common parameters such as Throughput, Reliability, End-to-End delay and Packet Delivery Ratio (PDR with increasing the numbers of nodes and increasing the speed of the nodes. The main objective of this work is to select the efficient multicast routing protocol for WSN among six multicast routing protocol based on relative strength and weakness of each protocol. The summary of above six multicast routing protocols is presented with a table of different performance characteristics. Experimental result shows that ODMRP attains higher throughput, reliability and higher packet delivery ratio than other multicast routing protocol, while incurring far less end-to-end delay.

  17. Dynamic Request Routing for Online Video-on-Demand Service: A Markov Decision Process Approach

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    Jianxiong Wan

    2014-01-01

    Full Text Available We investigate the request routing problem in the CDN-based Video-on-Demand system. We model the system as a controlled queueing system including a dispatcher and several edge servers. The system is formulated as a Markov decision process (MDP. Since the MDP formulation suffers from the so-called “the curse of dimensionality” problem, we then develop a greedy heuristic algorithm, which is simple and can be implemented online, to approximately solve the MDP model. However, we do not know how far it deviates from the optimal solution. To address this problem, we further aggregate the state space of the original MDP model and use the bounded-parameter MDP (BMDP to reformulate the system. This allows us to obtain a suboptimal solution with a known performance bound. The effectiveness of two approaches is evaluated in a simulation study.

  18. Robust On-Demand Multipath Routing with Dynamic Path Upgrade for Delay-Sensitive Data over Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Sunil Kumar

    2013-01-01

    Full Text Available Node mobility in mobile ad hoc networks (MANETs causes frequent route breakages and intermittent link stability. In this paper, we introduce a robust routing scheme, known as ad hoc on-demand multipath distance vector with dynamic path update (AOMDV-DPU, for delay-sensitive data transmission over MANET. The proposed scheme improves the AOMDV scheme by incorporating the following features: (i a routing metric based on the combination of minimum hops and received signal strength indicator (RSSI for discovery of reliable routes; (ii a local path update mechanism which strengthens the route, reduces the route breakage frequency, and increases the route longevity; (iii a keep alive mechanism for secondary route maintenance which enables smooth switching between routes and reduces the route discovery frequency; (iv a packet salvaging scheme to improve packet delivery in the event of a route breakage; and (v low HELLO packet overhead. The simulations are carried out in ns-2 for varying node speeds, number of sources, and traffic load conditions. Our AOMDV-DPU scheme achieves significantly higher throughput, lower delay, routing overhead, and route discovery frequency and latency compared to AOMDV. For H.264 compressed video traffic, AOMDV-DPU scheme achieves 3 dB or higher PSNR gain over AOMDV at both low and high node speeds.

  19. A Multipath Routing Protocol Based on Bloom Filter for Multihop Wireless Networks

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    Junwei Jin

    2016-01-01

    Full Text Available On-demand multipath routing in a wireless ad hoc network is effective in achieving load balancing over the network and in improving the degree of resilience to mobility. In this paper, the salvage capable opportunistic node-disjoint multipath routing (SNMR protocol is proposed, which forms multiple routes for data transmission and supports packet salvaging with minimum overhead. The proposed mechanism constructs a primary path and a node-disjoint backup path together with alternative paths for the intermediate nodes in the primary path. It can be achieved by considering the reverse route back to the source stored in the route cache and the primary path information compressed by a Bloom filter. Our protocol presents higher capability in packet salvaging and lower overhead in forming multiple routes. Simulation results show that SNMR outperforms the compared protocols in terms of packet delivery ratio, normalized routing load, and throughput.

  20. A Geographical Heuristic Routing Protocol for VANETs

    Science.gov (United States)

    Urquiza-Aguiar, Luis; Tripp-Barba, Carolina; Aguilar Igartua, Mónica

    2016-01-01

    Vehicular ad hoc networks (VANETs) leverage the communication system of Intelligent Transportation Systems (ITS). Recently, Delay-Tolerant Network (DTN) routing protocols have increased their popularity among the research community for being used in non-safety VANET applications and services like traffic reporting. Vehicular DTN protocols use geographical and local information to make forwarding decisions. However, current proposals only consider the selection of the best candidate based on a local-search. In this paper, we propose a generic Geographical Heuristic Routing (GHR) protocol that can be applied to any DTN geographical routing protocol that makes forwarding decisions hop by hop. GHR includes in its operation adaptations simulated annealing and Tabu-search meta-heuristics, which have largely been used to improve local-search results in discrete optimization. We include a complete performance evaluation of GHR in a multi-hop VANET simulation scenario for a reporting service. Our study analyzes all of the meaningful configurations of GHR and offers a statistical analysis of our findings by means of MANOVA tests. Our results indicate that the use of a Tabu list contributes to improving the packet delivery ratio by around 5% to 10%. Moreover, if Tabu is used, then the simulated annealing routing strategy gets a better performance than the selection of the best node used with carry and forwarding (default operation). PMID:27669254

  1. A Novel Smart Routing Protocol for Remote Health Monitoring in Medical Wireless Networks

    Directory of Open Access Journals (Sweden)

    T. V. P. Sundararajan

    2014-01-01

    Full Text Available In a Medical Wireless Network (MWN, sensors constantly monitor patient's physiological condition and movement. Inter-MWN communications are set up between the Patient Server and one or more Centralized Coordinators. However, MWNs require protocols with little energy consumption and the self-organizing attribute perceived in ad-hoc networks. The proposed Smart Routing Protocol (SRP selects only the nodes with a higher residual energy and lower traffic density for routing. This approach enhances cooperation among the nodes of a Mobile Ad Hoc Network. Consequently, SRP produces better results than the existing protocols, namely Conditional Min-Max Battery Cost Routing, Min-Max Battery Cost Routing and AdHoc On-demand Distance Vector in terms of network parameters. The performance of the erstwhile schemes for routing protocols is evaluated using the network simulator Qualnet v 4.5.

  2. A Clustering Routing Protocol for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Jinke Huang

    2016-01-01

    Full Text Available The dynamic topology of a mobile ad hoc network poses a real challenge in the design of hierarchical routing protocol, which combines proactive with reactive routing protocols and takes advantages of both. And as an essential technique of hierarchical routing protocol, clustering of nodes provides an efficient method of establishing a hierarchical structure in mobile ad hoc networks. In this paper, we designed a novel clustering algorithm and a corresponding hierarchical routing protocol for large-scale mobile ad hoc networks. Each cluster is composed of a cluster head, several cluster gateway nodes, several cluster guest nodes, and other cluster members. The proposed routing protocol uses proactive protocol between nodes within individual clusters and reactive protocol between clusters. Simulation results show that the proposed clustering algorithm and hierarchical routing protocol provide superior performance with several advantages over existing clustering algorithm and routing protocol, respectively.

  3. Advanced routing protocols for wireless networks

    CERN Document Server

    Campista , Miguel Elias Mitre

    2014-01-01

    This text introduces the principles of routing protocols and metrics as they affect wireless networking environments, specifically in urban areas. Timely because of the recent rise in small city life, this topic includes the consideration of ad hoc, mesh, vehicular, sensor, and delay tolerant networks. These approaches are each unique, and author Miguel Mitre Campista provides a thorough, but accessible, explanation of their individual characteristics for engineers, computer scientists, IT professionals, and curious Internet users.

  4. CBHRP: A Cluster Based Routing Protocol for Wireless Sensor Network

    OpenAIRE

    Rashed, M. G.; Kabir, M. Hasnat; Rahim, M. Sajjadur; Ullah, Sk. Enayet

    2012-01-01

    A new two layer hierarchical routing protocol called Cluster Based Hierarchical Routing Protocol (CBHRP) is proposed in this paper. It is an extension of LEACH routing protocol. We introduce cluster head-set idea for cluster-based routing where several clusters are formed with the deployed sensors to collect information from target field. On rotation basis, a head-set member receives data from the neighbor nodes and transmits the aggregated results to the distance base station. This protocol ...

  5. An improved AODV routing protocol based on tower structure

    Directory of Open Access Journals (Sweden)

    Li Yong Qiang

    2016-01-01

    Full Text Available The paper proposed a new routing protocol(IAODV based on tower structure in the Ad Hoc network for the problem which Location Routing Protocol need hardware and Complex algorithm. By the simulation, The complexity of the new routing protocol is reduced without reducing the performance of the network.

  6. Sigma Routing Metric for RPL Protocol

    Directory of Open Access Journals (Sweden)

    Paul Sanmartin

    2018-04-01

    Full Text Available This paper presents the adaptation of a specific metric for the RPL protocol in the objective function MRHOF. Among the functions standardized by IETF, we find OF0, which is based on the minimum hop count, as well as MRHOF, which is based on the Expected Transmission Count (ETX. However, when the network becomes denser or the number of nodes increases, both OF0 and MRHOF introduce long hops, which can generate a bottleneck that restricts the network. The adaptation is proposed to optimize both OFs through a new routing metric. To solve the above problem, the metrics of the minimum number of hops and the ETX are combined by designing a new routing metric called SIGMA-ETX, in which the best route is calculated using the standard deviation of ETX values between each node, as opposed to working with the ETX average along the route. This method ensures a better routing performance in dense sensor networks. The simulations are done through the Cooja simulator, based on the Contiki operating system. The simulations showed that the proposed optimization outperforms at a high margin in both OF0 and MRHOF, in terms of network latency, packet delivery ratio, lifetime, and power consumption.

  7. Intelligent QoS routing algorithm based on improved AODV protocol for Ad Hoc networks

    Science.gov (United States)

    Huibin, Liu; Jun, Zhang

    2016-04-01

    Mobile Ad Hoc Networks were playing an increasingly important part in disaster reliefs, military battlefields and scientific explorations. However, networks routing difficulties are more and more outstanding due to inherent structures. This paper proposed an improved cuckoo searching-based Ad hoc On-Demand Distance Vector Routing protocol (CSAODV). It elaborately designs the calculation methods of optimal routing algorithm used by protocol and transmission mechanism of communication-package. In calculation of optimal routing algorithm by CS Algorithm, by increasing QoS constraint, the found optimal routing algorithm can conform to the requirements of specified bandwidth and time delay, and a certain balance can be obtained among computation spending, bandwidth and time delay. Take advantage of NS2 simulation software to take performance test on protocol in three circumstances and validate the feasibility and validity of CSAODV protocol. In results, CSAODV routing protocol is more adapt to the change of network topological structure than AODV protocol, which improves package delivery fraction of protocol effectively, reduce the transmission time delay of network, reduce the extra burden to network brought by controlling information, and improve the routing efficiency of network.

  8. Bellman Ford algorithm - in Routing Information Protocol (RIP)

    Science.gov (United States)

    Krianto Sulaiman, Oris; Mahmud Siregar, Amir; Nasution, Khairuddin; Haramaini, Tasliyah

    2018-04-01

    In a large scale network need a routing that can handle a lot number of users, one of the solutions to cope with large scale network is by using a routing protocol, There are 2 types of routing protocol that is static and dynamic, Static routing is manually route input based on network admin, while dynamic routing is automatically route input formed based on existing network. Dynamic routing is efficient used to network extensively because of the input of route automatic formed, Routing Information Protocol (RIP) is one of dynamic routing that uses the bellman-ford algorithm where this algorithm will search for the best path that traversed the network by leveraging the value of each link, so with the bellman-ford algorithm owned by RIP can optimize existing networks.

  9. A Rule-Based Data Transfer Protocol for On-Demand Data Exchange in Vehicular Environment

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    Liao Hsien-Chou

    2009-01-01

    Full Text Available The purpose of Intelligent Transport System (ITS is mainly to increase the driving safety and efficiency. Data exchange is an important way to achieve the purpose. An on-demand data exchange is especially useful to assist a driver avoiding some emergent events. In order to handle the data exchange under dynamic situations, a rule-based data transfer protocol is proposed in this paper. A set of rules is designed according to the principle of request-forward-reply (RFR. That is, they are used to determine the timing of data broadcasting, forwarding, and replying automatically. Two typical situations are used to demonstrate the operation of rules. One is the front view of a driver occluded by other vehicles. The other is the traffic jam. The proposed protocol is flexible and extensible for unforeseen situations. Three simulation tools were also implemented to demonstrate the feasibility of the protocol and measure the network transmission under high density of vehicles. The simulation results show that the rule-based protocol is efficient on data exchange to increase the driving safety.

  10. Function-Oriented Networking and On-Demand Routing System in Network Using Ant Colony Optimization Algorithm

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    Young-Bo Sim

    2017-11-01

    Full Text Available In this paper, we proposed and developed Function-Oriented Networking (FON, a platform for network users. It has a different philosophy as opposed to technologies for network managers of Software-Defined Networking technology, OpenFlow. It is a technology that can immediately reflect the demands of the network users in the network, unlike the existing OpenFlow and Network Functions Virtualization (NFV, which do not reflect directly the needs of the network users. It allows the network user to determine the policy of the direct network, so it can be applied more precisely than the policy applied by the network manager. This is expected to increase the satisfaction of the service users when the network users try to provide new services. We developed FON function that performs on-demand routing for Low-Delay Required service. We analyzed the characteristics of the Ant Colony Optimization (ACO algorithm and found that the algorithm is suitable for low-delay required services. It was also the first in the world to implement the routing software using ACO Algorithm in the real Ethernet network. In order to improve the routing performance, several algorithms of the ACO Algorithm have been developed to enable faster path search-routing and path recovery. The relationship between the network performance index and the ACO routing parameters is derived, and the results are compared and analyzed. Through this, it was possible to develop the ACO algorithm.

  11. Intelligent routing protocol for ad hoc wireless network

    Science.gov (United States)

    Peng, Chaorong; Chen, Chang Wen

    2006-05-01

    A novel routing scheme for mobile ad hoc networks (MANETs), which combines hybrid and multi-inter-routing path properties with a distributed topology discovery route mechanism using control agents is proposed in this paper. In recent years, a variety of hybrid routing protocols for Mobile Ad hoc wireless networks (MANETs) have been developed. Which is proactively maintains routing information for a local neighborhood, while reactively acquiring routes to destinations beyond the global. The hybrid protocol reduces routing discovery latency and the end-to-end delay by providing high connectivity without requiring much of the scarce network capacity. On the other side the hybrid routing protocols in MANETs likes Zone Routing Protocol still need route "re-discover" time when a route between zones link break. Sine the topology update information needs to be broadcast routing request on local zone. Due to this delay, the routing protocol may not be applicable for real-time data and multimedia communication. We utilize the advantages of a clustering organization and multi-routing path in routing protocol to achieve several goals at the same time. Firstly, IRP efficiently saves network bandwidth and reduces route reconstruction time when a routing path fails. The IRP protocol does not require global periodic routing advertisements, local control agents will automatically monitor and repair broke links. Secondly, it efficiently reduces congestion and traffic "bottlenecks" for ClusterHeads in clustering network. Thirdly, it reduces significant overheads associated with maintaining clusters. Fourthly, it improves clusters stability due to dynamic topology changing frequently. In this paper, we present the Intelligent Routing Protocol. First, we discuss the problem of routing in ad hoc networks and the motivation of IRP. We describe the hierarchical architecture of IRP. We describe the routing process and illustrate it with an example. Further, we describe the control manage

  12. Performance Evaluation of AODV Routing Protocol in VANET with NS2

    Directory of Open Access Journals (Sweden)

    Divya Rathi

    2017-03-01

    Full Text Available In intelligent transportation systems, the collaboration between vehicles and the road side units is essential to bring these systems to realization. The emerging Vehicular Ad Hoc Network (VANET is becoming more and more important as it provides intelligent transportation application, comfort, safety, entertainment for people in vehicles. In order to provide stable routes and to get good performance in VANET, there is a need of proper routing protocols must be designed. In this paper, we are working with the very well-known ad-hoc on-demand distance vector (AODV routing protocol. The existing Routing protocol AODV-L which is based on the Link expiration time is extended to propose a more reliable AODV-AD which is based on multichannel MAC protocol. For the performance evaluation of routing protocols, a simulation tool ‘NS2’ has been used. Simulation results show that the proposed AODV-AD protocol can achieves better performances in forms of high Route stability, Packet Delivery ratio and packet loss rate than traditional AODV-L and traditional AODV.

  13. RSRP: A Robust Secure Routing Protocol in MANET

    Directory of Open Access Journals (Sweden)

    Sinha Ditipriya

    2014-05-01

    Full Text Available In this paper, we propose a novel algorithm RSRP to build a robust secure routing protocol in mobile ad-hoc networks (MANETs. This algorithm is based on some basic schemes such as RSA_CRT for encryption and decryption of messages; CRT for safety key generation, Shamir’s secret sharing principle for generation of secure routes. Those routes which are free from any malicious node and which belong to the set of disjoint routes between a source-destination pair are considered as probable routes. Shamir’s secret sharing principle is applied on those probable routes to obtain secure routes. Finally, most trustworthy and stable route is selected among those secure routes. Selection of the final route depends on some criteria of the nodes present in a route e.g.: battery power, mobility and trust value. In addition, complexity of key generation is reduced to a large extent by using RSA-CRT instead of RSA. In turn, the routing becomes less expensive and most secure and robust one. Performance of this routing protocol is then compared with non-secure routing protocols (AODV and DSR, secure routing scheme using secret sharing, security routing protocol using ZRP and SEAD depending on basic characteristics of these protocols. All such comparisons show that RSRP shows better performance in terms of computational cost, end-to-end delay and packet dropping in presence of malicious nodes in the MANET, keeping the overhead in terms of control packets same as other secure routing protocols.

  14. Evaluation and development the routing protocol of a fully functional simulation environment for VANETs

    Science.gov (United States)

    Ali, Azhar Tareq; Warip, Mohd Nazri Mohd; Yaakob, Naimah; Abduljabbar, Waleed Khalid; Atta, Abdu Mohammed Ali

    2017-11-01

    Vehicular Ad-hoc Networks (VANETs) is an area of wireless technologies that is attracting a great deal of interest. There are still several areas of VANETS, such as security and routing protocols, medium access control, that lack large amounts of research. There is also a lack of freely available simulators that can quickly and accurately simulate VANETs. The main goal of this paper is to develop a freely available VANETS simulator and to evaluate popular mobile ad-hoc network routing protocols in several VANETS scenarios. The VANETS simulator consisted of a network simulator, traffic (mobility simulator) and used a client-server application to keep the two simulators in sync. The VANETS simulator also models buildings to create a more realistic wireless network environment. Ad-Hoc Distance Vector routing (AODV), Dynamic Source Routing (DSR) and Dynamic MANET On-demand (DYMO) were initially simulated in a city, country, and highway environment to provide an overall evaluation.

  15. Routing protocol extension for resilient GMPLS multi-domain networks

    DEFF Research Database (Denmark)

    Manolova, Anna Vasileva; Ruepp, Sarah Renée; Romeral, Ricardo

    2010-01-01

    This paper evaluates the performance of multi-domain networks under the Generalized Multi-Protocol Label Switching control framework in case of a single inter-domain link failure. We propose and evaluate a routing protocol extension for the Border Gateway Protocol, which allows domains to obtain...... two Autonomous System disjoint paths and use them efficiently under failure conditions. Three main applications for the protocol extension are illustrated: reducing traffic loss on existing connections by xploiting pre-selected backup paths derived with our proposal, applying multi-domain restoration...... as survivability mechanism in case of single link failure, and employing proper failure notification mechanisms for routing of future connection requests under routing protocol re-convergence. Via simulations we illustrate the benefits of utilizing the proposed routing protocol extension for networks employing...

  16. A Survey of Routing Protocols in Wireless Body Sensor Networks

    Science.gov (United States)

    Bangash, Javed Iqbal; Abdullah, Abdul Hanan; Anisi, Mohammad Hossein; Khan, Abdul Waheed

    2014-01-01

    Wireless Body Sensor Networks (WBSNs) constitute a subset of Wireless Sensor Networks (WSNs) responsible for monitoring vital sign-related data of patients and accordingly route this data towards a sink. In routing sensed data towards sinks, WBSNs face some of the same routing challenges as general WSNs, but the unique requirements of WBSNs impose some more constraints that need to be addressed by the routing mechanisms. This paper identifies various issues and challenges in pursuit of effective routing in WBSNs. Furthermore, it provides a detailed literature review of the various existing routing protocols used in the WBSN domain by discussing their strengths and weaknesses. PMID:24419163

  17. Modelling and Initial Validation of the DYMO Routing Protocol for Mobile Ad-Hoc Networks

    DEFF Research Database (Denmark)

    Espensen, Kristian Asbjørn Leth; Kjeldsen, Mads Keblov; Kristensen, Lars Michael

    2008-01-01

    A mobile ad-hoc network (MANET) is an infrastructureless network established by a set of mobile devices using wireless communication. The Dynamic MANET On-demand (DYMO) protocol is a routing protocol for multi-hop communication in MANETs currently under development by the Internet Engineering Task...... Force (IETF). This paper presents a Coloured Petri Net (CPN) model of the mandatory parts of the DYMO protocol, and shows how scenario-based state space exploration has been used to validate key properties of the protocol. Our CPN modelling and verification work has spanned two revisions of the DYMO...... protocol specification and have had direct impact on the most recent version of the protocol specification....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-01-01

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

  19. Routing Protocols for Underwater Wireless Sensor Networks: Taxonomy, Research Challenges, Routing Strategies and Future Directions.

    Science.gov (United States)

    Khan, Anwar; Ali, Ihsan; Ghani, Abdullah; Khan, Nawsher; Alsaqer, Mohammed; Rahman, Atiq Ur; Mahmood, Hasan

    2018-05-18

    Recent research in underwater wireless sensor networks (UWSNs) has gained the attention of researchers in academia and industry for a number of applications. They include disaster and earthquake prediction, water quality and environment monitoring, leakage and mine detection, military surveillance and underwater navigation. However, the aquatic medium is associated with a number of limitations and challenges: long multipath delay, high interference and noise, harsh environment, low bandwidth and limited battery life of the sensor nodes. These challenges demand research techniques and strategies to be overcome in an efficient and effective fashion. The design of routing protocols for UWSNs is one of the promising solutions to cope with these challenges. This paper presents a survey of the routing protocols for UWSNs. For the ease of description, the addressed routing protocols are classified into two groups: localization-based and localization-free protocols. These groups are further subdivided according to the problems they address or the major parameters they consider during routing. Unlike the existing surveys, this survey considers only the latest and state-of-the-art routing protocols. In addition, every protocol is described in terms of its routing strategy and the problem it addresses and solves. The merit(s) of each protocol is (are) highlighted along with the cost. A description of the protocols in this fashion has a number of advantages for researchers, as compared to the existing surveys. Firstly, the description of the routing strategy of each protocol makes its routing operation easily understandable. Secondly, the demerit(s) of a protocol provides (provide) insight into overcoming its flaw(s) in future investigation. This, in turn, leads to the foundation of new protocols that are more intelligent, robust and efficient with respect to the desired parameters. Thirdly, a protocol can be selected for the appropriate application based on its described

  20. Perancangan dan Analisis Redistribution Routing Protocol OSPF dan EIGRP

    Directory of Open Access Journals (Sweden)

    DWI ARYANTA

    2014-07-01

    OSPF (Open Shortest Path First and EIGRP (Enhanced Interior Gateway Routing Protocol are two routing protocols are widely used in computer networks. Differences between the characteristics of routing protocols pose a problem in the delivery of data packets. Redistribution technique is the solution for communication between routing protocols. By using the software Cisco Packet Tracer 5.3 in this study were made simulating OSPF and EIGRP redistribution linked by technique, then compared its quality with a single EIGRP and OSPF routing protocols. Testing parameters in this study is the value of the time delay and trace route. Value trace route based on direct calculation of cost and metric compared with the simulation results. The result can be OSPF and EIGRP redistribution process. Value delay redistribution 1% better than OSPF and EIGRP 2-3% under traffic density dependent. In calculating the trace route redistribution is done 2 calculations, the cost for OSPF area and the area of the EIGRP metric. Making primary and alternate paths based on the packet delivery rate and the cost of the smallest metric, it is proved by calculation and simulation. Keywords: OSPF, EIGRP, Redistribution, Delay, Cost, Metric.

  1. Enhanced DSR Routing Protocol for the Short Time Disconnected MANET

    Directory of Open Access Journals (Sweden)

    PAPAJ Ján

    2013-05-01

    Full Text Available Data delivery in Mobile Ad-Hoc network (MANET is a very difficult task due to the fact the sporadic connections between mobile nodes. For this reason, we introduce the new modified routing protocol that enables the data delivery in the case that the connections are disconnected. A key aspect of the protocol is a process of finding connections between source and destination nodes that can provide low end-to-end delay and better delivery performance in a disconnected MANET. The protocol provides the concepts of opportunistic routing of the routing packets in disconnected MANETs. In this paper we present a modification of the DSR routing protocol and also some results of a simulation.

  2. Perancangan dan Analisis Redistribution Routing Protocol OSPF dan EIGRP

    Directory of Open Access Journals (Sweden)

    DWI ARYANTA

    2016-02-01

    Full Text Available Abstrak OSPF (Open Shortest Path First dan EIGRP (Enhanced Interior Gateway Routing Protocol adalah dua routing protokol yang banyak digunakan dalam jaringan komputer. Perbedaan karakteristik antar routing protokol menimbulkan masalah dalam pengiriman paket data. Teknik redistribution adalah solusi untuk melakukan komunikasi antar routing protokol. Dengan menggunakan software Cisco Packet Tracer 5.3 pada penelitian ini dibuat simulasi OSPF dan EIGRP yang dihubungkan oleh teknik redistribution, kemudian dibandingkan kualitasnya dengan single routing protokol EIGRP dan OSPF. Parameter pengujian dalam penelitian ini adalah nilai time delay dan trace route. Nilai trace route berdasarkan perhitungan langsung cost dan metric dibandingkan dengan hasil simulasi. Hasilnya dapat dilakukan proses redistribution OSPF dan EIGRP. Nilai delay redistribution lebih baik 1% dibanding OSPF dan 2-3% di bawah EIGRP tergantung kepadatan traffic. Dalam perhitungan trace route redistribution dilakukan 2 perhitungan, yaitu cost untuk area OSPF dan metric pada area EIGRP. Pengambilan jalur utama dan alternatif pengiriman paket berdasarkan nilai cost dan metric yang terkecil, hal ini terbukti berdasarkan perhitungan dan simulasi. Kata kunci: OSPF, EIGRP, Redistribution, Delay, Cost, Metric. Abstract OSPF (Open Shortest Path First and EIGRP (Enhanced Interior Gateway Routing Protocol are two routing protocols are widely used in computer networks. Differences between the characteristics of routing protocols pose a problem in the delivery of data packets. Redistribution technique is the solution for communication between routing protocols. By using the software Cisco Packet Tracer 5.3 in this study were made simulating OSPF and EIGRP redistribution linked by technique, then compared its quality with a single EIGRP and OSPF routing protocols. Testing parameters in this study is the value of the time delay and trace route. Value trace route based on direct calculation of cost

  3. Cluster Based Hierarchical Routing Protocol for Wireless Sensor Network

    OpenAIRE

    Rashed, Md. Golam; Kabir, M. Hasnat; Rahim, Muhammad Sajjadur; Ullah, Shaikh Enayet

    2012-01-01

    The efficient use of energy source in a sensor node is most desirable criteria for prolong the life time of wireless sensor network. In this paper, we propose a two layer hierarchical routing protocol called Cluster Based Hierarchical Routing Protocol (CBHRP). We introduce a new concept called head-set, consists of one active cluster head and some other associate cluster heads within a cluster. The head-set members are responsible for control and management of the network. Results show that t...

  4. The Comparative Study Some of Reactive and Proactive Routing Protocols in The Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Anas Ali Hussien

    2018-02-01

    Full Text Available The wireless sensor network (WSN consists mostly of a large number of nodes in a large area where not all nodes are directly connected. The applications of comprise a wide variety of scenarios.The mobile nodes are free to move because this network has selfــstructured topology. Routing protocols are responsible for detecting and maintaining paths in the network, and it classified into reactive (OnـــDemand, proactive (Table driven, and hybrid. In this paper represents a performance study of some WSN routing protocols: the Dynamic Source Routing (DSR, Ad hoc On-Demand Distance Vector (AODV, and Destination-Sequenced Distance-Vector (DSDV. The comparison made according to important metrics like packet delivery ratio (PDR, total packets dropped, Average end-to-end delay (Avg EED, and normalized routing load under the Transmission Control Protocol (TCP and User Datagram Protocol (UDP traffic connection and with varying number of nodes, pause time; and  varying speed. In this work used (NSــ2.35 that installed on (Ubuntu 14.04 operating system to implementing the scenario. Conclude that the DSR has better performance in TCP connection; while the DSDV has better performance in UDP protocol.

  5. A tree routing protocol for cognitive radio network

    Directory of Open Access Journals (Sweden)

    Mohammed Hashem

    2017-07-01

    Full Text Available Cognitive Radio (CR technology is an agile solution for spectrum congestion and spectrum access utilization problems that result from the legacy fixed spectrum management policies. CR technology can exploit unused licensed band to meet the increasing demand for radio frequency. The routing process faces many challenges in CR Network (CRN such as the absence of centralized infrastructure, the coordination between the routing module and spectrum management module, in addition to the frequent link failure due to the sudden appearance of PUs. In this paper we propose a Tree routing protocol for cognitive radio network (C-TRP that jointly utilizes the tree routing algorithm with a spectrum management module in routing decisions, and also we proposed a new metric used in taking the best route decisions. In addition, we enhance the traditional tree routing algorithm by using a neighbor table technique that speeds up the forwarding data packets. Moreover, we add a robust recovery module to C-TRP to resume the network in case of the link failure. The main motivation in the design of C-TRP is quick data transmission and maximization of date rates. The performance evaluation is carried out in NS2 simulator. The simulation results proved that C-TRP protocol achieves better performance in terms of average “PDR”, “end-to-end delay” and “routing overhead ratio “compared to “CTBR” and “STOD-RP” routing protocols.

  6. Performance analysis of routing protocols for IoT

    Science.gov (United States)

    Manda, Sridhar; Nalini, N.

    2018-04-01

    Internet of Things (IoT) is an arrangement of advancements that are between disciplinary. It is utilized to have compelling combination of both physical and computerized things. With IoT physical things can have personal virtual identities and participate in distributed computing. Realization of IoT needs the usage of sensors based on the sector for which IoT is integrated. For instance, in healthcare domain, IoT needs to have integration with wearable sensors used by patients. As sensor devices produce huge amount of data, often called big data, there should be efficient routing protocols in place. To the extent remote systems is worried there are some current protocols, for example, OLSR, DSR and AODV. It additionally tosses light into Trust based routing protocol for low-power and lossy systems (TRPL) for IoT. These are broadly utilized remote directing protocols. As IoT is developing round the corner, it is basic to investigate routing protocols that and evaluate their execution regarding throughput, end to end delay, and directing overhead. The execution experiences can help in settling on very much educated choices while incorporating remote systems with IoT. In this paper, we analyzed different routing protocols and their performance is compared. It is found that AODV showed better performance than other routing protocols aforementioned.

  7. Optimized energy-delay sub-network routing protocol development and implementation for wireless sensor networks

    International Nuclear Information System (INIS)

    Fonda, James W; Zawodniok, Maciej; Jagannathan, S; Watkins, Steve E

    2008-01-01

    The development and the implementation issues of a reactive optimized energy-delay sub-network routing (OEDSR) protocol for wireless sensor networks (WSN) are introduced and its performance is contrasted with the popular ad hoc on-demand distance vector (AODV) routing protocol. Analytical results illustrate the performance of the proposed OEDSR protocol, while experimental results utilizing a hardware testbed under various scenarios demonstrate improvements in energy efficiency of the OEDSR protocol. A hardware platform constructed at the University of Missouri-Rolla (UMR), now the Missouri University of Science and Technology (MST), based on the Generation 4 Smart Sensor Node (G4-SSN) prototyping platform is also described. Performance improvements are shown in terms of end-to-end (E2E) delay, throughput, route-set-up time and drop rates and energy usage is given for three topologies, including a mobile topology. Additionally, results from the hardware testbed provide valuable lessons for network deployments. Under testing OEDSR provides a factor of ten improvement in the energy used in the routing session and extends network lifetime compared to AODV. Depletion experiments show that the time until the first node failure is extended by a factor of three with the network depleting and network lifetime is extended by 6.7%

  8. An Improved 6LoWPAN Hierarchical Routing Protocol

    Directory of Open Access Journals (Sweden)

    Xue Li

    2015-10-01

    Full Text Available IETF 6LoWPAN working group is engaged in the IPv6 protocol stack research work based on IEEE802.15.4 standard. In this working group, the routing protocol is one of the important research contents. In the 6LoWPAN, HiLow is a well-known layered routing protocol. This paper puts forward an improved hierarchical routing protocol GHiLow by improving HiLow parent node selection and path restoration strategy. GHiLow improves the parent node selection by increasing the choice of parameters. Simutaneously, it also improves path recovery by analysing different situations to recovery path. Therefore, GHiLow contributes to the ehancement of network performance and the decrease of network energy consumption.

  9. Management of Energy Consumption on Cluster Based Routing Protocol for MANET

    Science.gov (United States)

    Hosseini-Seno, Seyed-Amin; Wan, Tat-Chee; Budiarto, Rahmat; Yamada, Masashi

    The usage of light-weight mobile devices is increasing rapidly, leading to demand for more telecommunication services. Consequently, mobile ad hoc networks and their applications have become feasible with the proliferation of light-weight mobile devices. Many protocols have been developed to handle service discovery and routing in ad hoc networks. However, the majority of them did not consider one critical aspect of this type of network, which is the limited of available energy in each node. Cluster Based Routing Protocol (CBRP) is a robust/scalable routing protocol for Mobile Ad hoc Networks (MANETs) and superior to existing protocols such as Ad hoc On-demand Distance Vector (AODV) in terms of throughput and overhead. Therefore, based on this strength, methods to increase the efficiency of energy usage are incorporated into CBRP in this work. In order to increase the stability (in term of life-time) of the network and to decrease the energy consumption of inter-cluster gateway nodes, an Enhanced Gateway Cluster Based Routing Protocol (EGCBRP) is proposed. Three methods have been introduced by EGCBRP as enhancements to the CBRP: improving the election of cluster Heads (CHs) in CBRP which is based on the maximum available energy level, implementing load balancing for inter-cluster traffic using multiple gateways, and implementing sleep state for gateway nodes to further save the energy. Furthermore, we propose an Energy Efficient Cluster Based Routing Protocol (EECBRP) which extends the EGCBRP sleep state concept into all idle member nodes, excluding the active nodes in all clusters. The experiment results show that the EGCBRP decreases the overall energy consumption of the gateway nodes up to 10% and the EECBRP reduces the energy consumption of the member nodes up to 60%, both of which in turn contribute to stabilizing the network.

  10. A source-initiated on-demand routing algorithm based on the Thorup-Zwick theory for mobile wireless sensor networks.

    Science.gov (United States)

    Mao, Yuxin; Zhu, Ping

    2013-01-01

    The unreliability and dynamics of mobile wireless sensor networks make it hard to perform end-to-end communications. This paper presents a novel source-initiated on-demand routing mechanism for efficient data transmission in mobile wireless sensor networks. It explores the Thorup-Zwick theory to achieve source-initiated on-demand routing with time efficiency. It is able to find out shortest routing path between source and target in a network and transfer data in linear time. The algorithm is easy to be implemented and performed in resource-constrained mobile wireless sensor networks. We also evaluate the approach by analyzing its cost in detail. It can be seen that the approach is efficient to support data transmission in mobile wireless sensor networks.

  11. Evaluation of svr: a wireless sensor network routing protocol

    International Nuclear Information System (INIS)

    Baloch, J.; Khanzada, T.J.S.

    2014-01-01

    The advancement in technology has made it possible to create small in size, low cost sensor nodes. However, the small size and low cost of such nodes comesat at price that is, reduced processing power, low memory and significantly small battery energy storage. WSNs (Wireless Sensor Networks) are inherently ad hoc in nature and are assumed to work in the toughest terrain. The network lifetime plays a pivotal role in a wireless sensor network. A long network lifetime, could be achieved by either making significant changes in these low cost devices, which is not a feasible solution or by improving the means of communication throughout the network. The communication in such networks could be improved by employing energy efficient routing protocols, to route the data throughout the network. In this paper the SVR (Spatial Vector Routing) protocol is compared against the most common WSN routing protocols, and from the results it could be inferred that the SVR protocol out performs its counterparts. The protocol provides an energy efficient means of communication in the network. (author)

  12. A security analysis of the 802.11s wireless mesh network routing protocol and its secure routing protocols.

    Science.gov (United States)

    Tan, Whye Kit; Lee, Sang-Gon; Lam, Jun Huy; Yoo, Seong-Moo

    2013-09-02

    Wireless mesh networks (WMNs) can act as a scalable backbone by connecting separate sensor networks and even by connecting WMNs to a wired network. The Hybrid Wireless Mesh Protocol (HWMP) is the default routing protocol for the 802.11s WMN. The routing protocol is one of the most important parts of the network, and it requires protection, especially in the wireless environment. The existing security protocols, such as the Broadcast Integrity Protocol (BIP), Counter with cipher block chaining message authentication code protocol (CCMP), Secure Hybrid Wireless Mesh Protocol (SHWMP), Identity Based Cryptography HWMP (IBC-HWMP), Elliptic Curve Digital Signature Algorithm HWMP (ECDSA-HWMP), and Watchdog-HWMP aim to protect the HWMP frames. In this paper, we have analyzed the vulnerabilities of the HWMP and developed security requirements to protect these identified vulnerabilities. We applied the security requirements to analyze the existing secure schemes for HWMP. The results of our analysis indicate that none of these protocols is able to satisfy all of the security requirements. We also present a quantitative complexity comparison among the protocols and an example of a security scheme for HWMP to demonstrate how the result of our research can be utilized. Our research results thus provide a tool for designing secure schemes for the HWMP.

  13. Analysis of Pervasive Mobile Ad Hoc Routing Protocols

    Science.gov (United States)

    Qadri, Nadia N.; Liotta, Antonio

    Mobile ad hoc networks (MANETs) are a fundamental element of pervasive networks and therefore, of pervasive systems that truly support pervasive computing, where user can communicate anywhere, anytime and on-the-fly. In fact, future advances in pervasive computing rely on advancements in mobile communication, which includes both infrastructure-based wireless networks and non-infrastructure-based MANETs. MANETs introduce a new communication paradigm, which does not require a fixed infrastructure - they rely on wireless terminals for routing and transport services. Due to highly dynamic topology, absence of established infrastructure for centralized administration, bandwidth constrained wireless links, and limited resources in MANETs, it is challenging to design an efficient and reliable routing protocol. This chapter reviews the key studies carried out so far on the performance of mobile ad hoc routing protocols. We discuss performance issues and metrics required for the evaluation of ad hoc routing protocols. This leads to a survey of existing work, which captures the performance of ad hoc routing algorithms and their behaviour from different perspectives and highlights avenues for future research.

  14. Energy Aware GPSR Routing Protocol in a Wireless Sensor Network ...

    African Journals Online (AJOL)

    Energy is the scarce resource in wireless sensor networks (WSNs), and it determines the lifetime of WSNs. For this reason, WSN algorithms and routing protocols should be selected in a manner which fulfills these energy requirements. This paper presents a solution to increase the lifetime of WSNs by decreasing their ...

  15. A Novel Load Balancing Scheme for Multipath Routing Protocol in MANET

    Directory of Open Access Journals (Sweden)

    Kokilamani Mounagurusamy

    2016-09-01

    Full Text Available The recent advancements in information and communication technology create a great demand for multipath routing protocols. In MANET, nodes can be arbitrarily located and can move freely at any given time. The topology of MANET can change rapidly and unpredictably. Because wireless link capacities are usually limited, congestion is possible in MANETs. Hence, balancing the load in a MANET is important since nodes with high load will deplete their batteries quickly, thereby increasing the probability of disconnecting or partitioning the network. To overcome these, the multipath protocol should be aware of load at route discovery phase. The main objective of the proposed article is to balance the load on a node and to extend the lifetime of the node due to the congestion, energy depletion and link failures. This article describes a novel load and congestion aware scheme called Path Efficient Ad-hoc On-demand Multipath Distance Vector (PE-AOMDV protocol to increase the performance of routing process in MANET in terms of congestion, end-to-end delay and load balancing. A new threshold value and a counter variable are introduced to limit the number of communication paths passing over a node in route discovery phase. For every new request the counter variable is incremented by one and the threshold value is compared to see whether the maximum number of connections has been reached or not. The proposed method is network simulator ns-2 and it is found that there is a significant improvement in the proposed scheme. It reduces the energy consumption, average end-to-end delay and normalized routing overhead. Also the proposed scheme increases packet delivery ratio, throughput and minimizes routing overheads.

  16. Interface Assignment-Based AODV Routing Protocol to Improve Reliability in Multi-Interface Multichannel Wireless Mesh Networks

    Directory of Open Access Journals (Sweden)

    Won-Suk Kim

    2015-01-01

    Full Text Available The utilization of wireless mesh networks (WMNs has greatly increased, and the multi-interface multichannel (MIMC technic has been widely used for the backbone network. Unfortunately, the ad hoc on-demand distance vector (AODV routing protocol defined in the IEEE 802.11s standard was designed for WMNs using the single-interface single-channel technic. So, we define a problem that happens when the legacy AODV is used in MIMC WMNs and propose an interface assignment-based AODV (IA-AODV in order to resolve that problem. IA-AODV, which is based on multitarget path request, consists of the PREQ prediction scheme, the PREQ loss recovery scheme, and the PREQ sender assignment scheme. A detailed operation according to various network conditions and services is introduced, and the routing efficiency and network reliability of a network using IA-AODV are analyzed over the presented system model. Finally, after a real-world test-bed for MIMC WMNs using the IA-AODV routing protocol is implemented, the various indicators of the network are evaluated through experiments. When the proposed routing protocol is compared with the existing AODV routing protocol, it performs the path update using only 14.33% of the management frames, completely removes the routing malfunction, and reduces the UDP packet loss ratio by 0.0012%.

  17. Performance modeling of neighbor discovery in proactive routing protocols

    Directory of Open Access Journals (Sweden)

    Andres Medina

    2011-07-01

    Full Text Available It is well known that neighbor discovery is a critical component of proactive routing protocols in wireless ad hoc networks. However there is no formal study on the performance of proposed neighbor discovery mechanisms. This paper provides a detailed model of key performance metrics of neighbor discovery algorithms, such as node degree and the distribution of the distance to symmetric neighbors. The model accounts for the dynamics of neighbor discovery as well as node density, mobility, radio and interference. The paper demonstrates a method for applying these models to the evaluation of global network metrics. In particular, it describes a model of network connectivity. Validation of the models shows that the degree estimate agrees, within 5% error, with simulations for the considered scenarios. The work presented in this paper serves as a basis for the performance evaluation of remaining performance metrics of routing protocols, vital for large scale deployment of ad hoc networks.

  18. Congestion control for vehicular delay tolerant network routing protocols

    OpenAIRE

    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...

  19. Cluster chain based energy efficient routing protocol for moblie WSN

    Directory of Open Access Journals (Sweden)

    WU Ziyu

    2016-04-01

    Full Text Available With the ubiquitous smart devices acting as mobile sensor nodes in the wireless sensor networks(WSNs to sense and transmit physical information,routing protocols should be designed to accommodate the mobility issues,in addition to conventional considerations on energy efficiency.However,due to frequent topology change,traditional routing schemes cannot perform well.Moreover,existence of mobile nodes poses new challenges on energy dissipation and packet loss.In this paper,a novel routing scheme called cluster chain based routing protocol(CCBRP is proposed,which employs a combination of cluster and chain structure to accomplish data collection and transmission and thereafter selects qualified cluster heads as chain leaders to transmit data to the sink.Furthermore,node mobility is handled based on periodical membership update of mobile nodes.Simulation results demonstrate that CCBRP has a good performance in terms of network lifetime and packet delivery,also strikes a better balance between successful packet reception and energy consumption.

  20. Routing Protocol for Mobile Ad-hoc Wireless Networks

    Directory of Open Access Journals (Sweden)

    I. M. B. Nogales

    2007-09-01

    Full Text Available Bluetooth is a cutting-edge technology used for implementing wireless ad hoc networks. In order to provide an overall scheme for mobile ad hoc networks, this paper deals with scatternet topology formation and routing algorithm to form larger ad hoc wireless Networks. Scatternet topology starts by forming a robust network, which is less susceptible to the problems posed by node mobility. Mobile topology relies on the presence of free nodes that create multiple connections with the network and on their subsequently rejoining the network. Our routing protocol is a proactive routing protocol, which is tailor made for the Bluetooth ad hoc network. The connection establishment connects nodes in a structure that simplifies packet routing and scheduling. The design allows nodes to arrive and leave arbitrarily, incrementally building the topology and healing partitions when they occur. We present simulation results that show that the algorithm presents low formation latency and also generates an efficient topology for forwarding packets along ad-hoc wireless networks.

  1. A Secure Cluster-Based Multipath Routing Protocol for WMSNs

    Directory of Open Access Journals (Sweden)

    Jamal N. Al-Karaki

    2011-04-01

    Full Text Available The new characteristics of Wireless Multimedia Sensor Network (WMSN and its design issues brought by handling different traffic classes of multimedia content (video streams, audio, and still images as well as scalar data over the network, make the proposed routing protocols for typical WSNs not directly applicable for WMSNs. Handling real-time multimedia data requires both energy efficiency and QoS assurance in order to ensure efficient utility of different capabilities of sensor resources and correct delivery of collected information. In this paper, we propose a Secure Cluster-based Multipath Routing protocol for WMSNs, SCMR, to satisfy the requirements of delivering different data types and support high data rate multimedia traffic. SCMR exploits the hierarchical structure of powerful cluster heads and the optimized multiple paths to support timeliness and reliable high data rate multimedia communication with minimum energy dissipation. Also, we present a light-weight distributed security mechanism of key management in order to secure the communication between sensor nodes and protect the network against different types of attacks. Performance evaluation from simulation results demonstrates a significant performance improvement comparing with existing protocols (which do not even provide any kind of security feature in terms of average end-to-end delay, network throughput, packet delivery ratio, and energy consumption.

  2. A SURVEY on WIRELESS MESH NETWORKS, ROUTING METRICS and PROTOCOLS

    Directory of Open Access Journals (Sweden)

    Safak DURUKAN ODABASI

    2013-01-01

    Full Text Available Today, Internet has become an indispensable part of our daily lives. It has a growing user community in many fields from banking transactions to online entertainment. It will be very efficient for users, as the next generation internet access becomes wireless like frequently used services such as cellular phones. But for providing this, a new network is needed to be designed or an existing network must be improved as well as making changes on infrastructure. At this point, mesh network infrastructure arises and offers more sophisticated internet access with less need. The most important advantage of mesh networks is the capability of working without infrastructure. Mesh networks are an additional access technology more than being a renewed one in the next generation wireless networks called 4G. In this study, wireless mesh networks and example applications are mentioned. Base architecture and design factors are emphasized, current routing protocols that are used on wireless mesh networks and routing metrics on which these protocols are based, are explained. Finally, the performance effects of these protocols and metrics on different network topologies are referred.

  3. Comparison of MANET Routing Protocols in Different Traffic and Mobility Models

    Directory of Open Access Journals (Sweden)

    J. Baraković

    2010-06-01

    Full Text Available Routing protocol election in MANET (Mobile Ad Hoc Network is a great challenge, because of its frequent topology changes and routing overhead. This paper compares performances of three routing protocols: Destination Sequenced Distance Vector (DSDV, Ad Hoc Ondemand Distance Vector (AODV and Dynamic Source Routing (DSR, based on results analysis obtained using simulations with different load and mobility scenarios performed with Network Simulator version 2 (NS-2. In low load and low mobility scenarios routing protocols perform in a similar manner. However, with mobility and load increasing DSR outperforms AODV and DSDV protocols.

  4. A two-hop based adaptive routing protocol for real-time wireless sensor networks.

    Science.gov (United States)

    Rachamalla, Sandhya; Kancherla, Anitha Sheela

    2016-01-01

    One of the most important and challenging issues in wireless sensor networks (WSNs) is to optimally manage the limited energy of nodes without degrading the routing efficiency. In this paper, we propose an energy-efficient adaptive routing mechanism for WSNs, which saves energy of nodes by removing the much delayed packets without degrading the real-time performance of the used routing protocol. It uses the adaptive transmission power algorithm which is based on the attenuation of the wireless link to improve the energy efficiency. The proposed routing mechanism can be associated with any geographic routing protocol and its performance is evaluated by integrating with the well known two-hop based real-time routing protocol, PATH and the resulting protocol is energy-efficient adaptive routing protocol (EE-ARP). The EE-ARP performs well in terms of energy consumption, deadline miss ratio, packet drop and end-to-end delay.

  5. Performance evaluation of spatial vector routing protocol for wireless sensor networks

    International Nuclear Information System (INIS)

    Baloch, J.; Jokhio, I.

    2012-01-01

    WSNs (Wireless Sensor Networks) is an emerging area of research. Researchers worldwide are working on the issues faced by sensor nodes. Communication has been a major issue in wireless networks and the problem is manifolds in WSN s because of the limited resources. The routing protocol in such networks plays a pivotal role, as an effective routing protocol could significantly reduce the energy consumed in transmitting and receiving data packets throughout a network. In this paper the performance of SVR (Spatial Vector Routing) an energy efficient, location aware routing protocol is compared with the existing location aware protocols. The results from the simulation trials show the performance of SVR. (author)

  6. Performance Evaluation of Spatial Vector Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Javed Ali Baloch

    2012-10-01

    Full Text Available WSNs (Wireless Sensor Networks is an emerging area of research. Researchers worldwide are working on the issues faced by sensor nodes. Communication has been a major issue in wireless networks and the problem is manifolds in WSNs because of the limited resources. The routing protocol in such networks plays a pivotal role, as an effective routing protocol could significantly reduce the energy consumed in transmitting and receiving data packets throughout a network. In this paper the performance of SVR (Spatial Vector Routing an energy efficient, location aware routing protocol is compared with the existing location aware protocols. The results from the simulation trials show the performance of SVR.

  7. Energy-Aware Routing Protocol for Ad Hoc Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mann Raminder P

    2005-01-01

    Full Text Available Wireless ad hoc sensor networks differ from wireless ad hoc networks from the following perspectives: low energy, lightweight routing protocols, and adaptive communication patterns. This paper proposes an energy-aware routing protocol (EARP suitable for ad hoc wireless sensor networks and presents an analysis for its energy consumption in various phases of route discovery and maintenance. Based on the energy consumption associated with route request processing, EARP advocates the minimization of route requests by allocating dynamic route expiry times. This paper introduces a unique mechanism for estimation of route expiry time based on the probability of route validity, which is a function of time, number of hops, and mobility parameters. In contrast to AODV, EARP reduces the repeated flooding of route requests by maintaining valid routes for longer durations.

  8. Towards designing energy-efficient routing protocol for wireless mesh networks

    CSIR Research Space (South Africa)

    Dludla, AG

    2009-08-01

    Full Text Available Different studies have proposed number of routing protocols to overcome data transmission challenges. Very few of these protocols consider node energy. In this study, the state of art work from various studies is reviewed and compared based...

  9. Cost analysis of hybrid adaptive routing protocol for heterogeneous ...

    Indian Academy of Sciences (India)

    NONITA SHARMA

    Event detection; wireless sensor networks; hybrid routing; cost benefit analysis; proactive routing; reactive routing. 1. ... additional energy, high processing power, etc. are deployed to extend the .... transmit to its parent node. (2) Reactive ...

  10. Real-Time QoS Routing Protocols in Wireless Multimedia Sensor Networks: Study and Analysis.

    Science.gov (United States)

    Alanazi, Adwan; Elleithy, Khaled

    2015-09-02

    Many routing protocols have been proposed for wireless sensor networks. These routing protocols are almost always based on energy efficiency. However, recent advances in complementary metal-oxide semiconductor (CMOS) cameras and small microphones have led to the development of Wireless Multimedia Sensor Networks (WMSN) as a class of wireless sensor networks which pose additional challenges. The transmission of imaging and video data needs routing protocols with both energy efficiency and Quality of Service (QoS) characteristics in order to guarantee the efficient use of the sensor nodes and effective access to the collected data. Also, with integration of real time applications in Wireless Senor Networks (WSNs), the use of QoS routing protocols is not only becoming a significant topic, but is also gaining the attention of researchers. In designing an efficient QoS routing protocol, the reliability and guarantee of end-to-end delay are critical events while conserving energy. Thus, considerable research has been focused on designing energy efficient and robust QoS routing protocols. In this paper, we present a state of the art research work based on real-time QoS routing protocols for WMSNs that have already been proposed. This paper categorizes the real-time QoS routing protocols into probabilistic and deterministic protocols. In addition, both categories are classified into soft and hard real time protocols by highlighting the QoS issues including the limitations and features of each protocol. Furthermore, we have compared the performance of mobility-aware query based real-time QoS routing protocols from each category using Network Simulator-2 (NS2). This paper also focuses on the design challenges and future research directions as well as highlights the characteristics of each QoS routing protocol.

  11. A Family of ACO Routing Protocols for Mobile Ad Hoc Networks

    Science.gov (United States)

    Rupérez Cañas, Delfín; Sandoval Orozco, Ana Lucila; García Villalba, Luis Javier; Kim, Tai-hoon

    2017-01-01

    In this work, an ACO routing protocol for mobile ad hoc networks based on AntHocNet is specified. As its predecessor, this new protocol, called AntOR, is hybrid in the sense that it contains elements from both reactive and proactive routing. Specifically, it combines a reactive route setup process with a proactive route maintenance and improvement process. Key aspects of the AntOR protocol are the disjoint-link and disjoint-node routes, separation between the regular pheromone and the virtual pheromone in the diffusion process and the exploration of routes, taking into consideration the number of hops in the best routes. In this work, a family of ACO routing protocols based on AntOR is also specified. These protocols are based on protocol successive refinements. In this work, we also present a parallelized version of AntOR that we call PAntOR. Using programming multiprocessor architectures based on the shared memory protocol, PAntOR allows running tasks in parallel using threads. This parallelization is applicable in the route setup phase, route local repair process and link failure notification. In addition, a variant of PAntOR that consists of having more than one interface, which we call PAntOR-MI (PAntOR-Multiple Interface), is specified. This approach parallelizes the sending of broadcast messages by interface through threads. PMID:28531159

  12. A Family of ACO Routing Protocols for Mobile Ad Hoc Networks.

    Science.gov (United States)

    Rupérez Cañas, Delfín; Sandoval Orozco, Ana Lucila; García Villalba, Luis Javier; Kim, Tai-Hoon

    2017-05-22

    In this work, an ACO routing protocol for mobile ad hoc networks based on AntHocNet is specified. As its predecessor, this new protocol, called AntOR, is hybrid in the sense that it contains elements from both reactive and proactive routing. Specifically, it combines a reactive route setup process with a proactive route maintenance and improvement process. Key aspects of the AntOR protocol are the disjoint-link and disjoint-node routes, separation between the regular pheromone and the virtual pheromone in the diffusion process and the exploration of routes, taking into consideration the number of hops in the best routes. In this work, a family of ACO routing protocols based on AntOR is also specified. These protocols are based on protocol successive refinements. In this work, we also present a parallelized version of AntOR that we call PAntOR. Using programming multiprocessor architectures based on the shared memory protocol, PAntOR allows running tasks in parallel using threads. This parallelization is applicable in the route setup phase, route local repair process and link failure notification. In addition, a variant of PAntOR that consists of having more than one interface, which we call PAntOR-MI (PAntOR-Multiple Interface), is specified. This approach parallelizes the sending of broadcast messages by interface through threads.

  13. Compromises Between Quality of Service Metrics and Energy Consumption of Hierarchical and Flat Routing Protocols for Wireless Sensors Network

    Directory of Open Access Journals (Sweden)

    Abdelbari BEN YAGOUTA

    2016-11-01

    Full Text Available Wireless Sensor Network (WSN is wireless network composed of spatially distributed and tiny autonomous nodes, which cooperatively monitor physical or environmental conditions. Among the concerns of these networks is prolonging the lifetime by saving nodes energy. There are several protocols specially designed for WSNs based on energy conservation. However, many WSNs applications require QoS (Quality of Service criteria, such as latency, reliability and throughput. In this paper, we will compare three routing protocols for wireless sensors network LEACH (Low Energy Adaptive Clustering Hierarchy, AODV (Ad hoc on demand Distance Vector and LABILE (Link Quality-Based Lexical Routing using Castalia simulator in terms of energy consumption, throughput, reliability and latency time of packets received by sink under different conditions to determinate the best configurations that offers the most suitable compromises between energy conservation and all QoS metrics for each routing protocols. The results show that, the best configurations that offer the suitable compromises between energy conservation and all QoS metrics is a large number of deployed nodes with low packet rate for LEACH (300 nodes and 1 packet/s, a medium number of deployed nodes with low packet rate For AODV (100 nodes and 1 packet/s and a very low nodes density with low packet rate for LABILE (50 nodes and 1 packet/s.

  14. Energy efficient routing protocols for wireless sensor networks: comparison and future directions

    Directory of Open Access Journals (Sweden)

    Loganathan Murukesan

    2017-01-01

    Full Text Available Wireless sensor network consists of nodes with limited resources. Hence, it is important to design protocols or algorithms which increases energy efficiency in order to improve the network lifetime. In this paper, techniques used in the network layer (routing of the internet protocol stack to achieve energy efficiency are reviewed. Usually, the routing protocols are classified into four main schemes: (1 Network Structure, (2 Communication Model, (3 Topology Based, and (4 Reliable Routing. In this work, only network structure based routing protocols are reviewed due to the page constraint. Besides, this type of protocols are much popular among the researchers since they are fairly simple to implement and produce good results as presented in this paper. Also, the pros and cons of each protocols are presented. Finally, the paper concludes with possible further research directions.

  15. Routing protocols for wireless sensor networks: What the literature says?

    Directory of Open Access Journals (Sweden)

    Amit Sarkar

    2016-12-01

    Full Text Available Routing in Wireless Sensor Networks (WSNs plays a significant role in the field of environment-oriented monitoring, traffic monitoring, etc. Here, wide contributions that are made toward routing in WSN are explored. The paper mainly aims to categorize the routing problems and examines the routing-related optimization problems. For achieving the motive, 50 papers from the standard journals are collected and primarily reviewed in a chronological way. Later, various features that are related to energy, security, speed and reliability problems of routing are discussed. Subsequently, the literature is analyzed based on the simulation environment and experimental setup, awareness over the Quality of Service (QoS and the deployment against various applications. In addition, the optimization of the routing algorithms and the meta-heuristic study of routing optimization are explored. Routing is a vast area with numerous unsolved issues and hence, various research gaps along with future directions are also presented.

  16. A Performance Study of LEACH and Direct Diffusion Routing Protocols in Wireless Sensor Network

    International Nuclear Information System (INIS)

    Fakher, S.; Sharshar, K.; Moawad, M.I.; Shokair, M.

    2016-01-01

    The Wireless Sensor Network (WSN) is composed of a large number of sensor nodes with limited computation communication, and battery facilities. One of the common applications of this network is environment monitoring through sensing motion, measuring temperature, humidity and radiation. One of the basic activities in WSN is data gathering which represents a great challenge. Many routing protocols are proposed for that network to collect and aggregate the data. The most popular ones are hierarchy and data centric routing protocols. The main goal of this study is to identify the most preferable routing protocol, to be used in each mobility model. This paper studies the performance of LEACH (Low Energy Adaptive Clustering Hierarchy) from hierarchy routing protocol and direct diffusion from data centric routing protocol which is not clarified until now. Moreover, a comparison between LEACH and direct diffusion protocol using NS2 simulator will be made, and an analysis of these protocols will be conducted. The comparison includes packet delivery ratio, throughput, average energy ratio, average delay, network lifetime, and routing overhead. The performance is evaluated by varying the number of sensor nodes under three mobility models Reference Point Group Mobility Model (RPGM), Manhattan and random waypoint mobility model. Simulation results show that LEACH routing protocol has a good performance in RPGM and Manhattan than random waypoint mobility model. Direct diffusion has a good performance in random waypoint mobility model than in RPGM and Manhattan mobility model

  17. A MODIFIED ROUTE DISCOVERY APPROACH FOR DYNAMIC SOURCE ROUTING (DSR PROTOCOL IN MOBILE AD-HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    Alaa Azmi Allahham

    2017-02-01

    Full Text Available Mobile Ad-hoc networks (MANETs involved in many applications, whether commercial or military because of their characteristics that do not depend on the infrastructure as well as the freedom movement of their elements, but in return has caused this random mobility of the nodes many of the challenges, where the routing is considered one of these challenges. There are many types of routing protocols that operate within MANET networks, which responsible for finding paths between the source and destination nodes with the modernization of these paths which are constantly changing due to the dynamic topology of the network stemming from the constant random movement of the nodes. The DSR (Dynamic Source Routing routing protocol algorithm is one of these routing protocols which consist of two main stages; route discovery and maintenance, where the route discovery algorithm operates based on blind flooding of request messages. blind flooding is considered as the most well known broadcasting mechanism, it is inefficient in terms of communication and resource utilization, which causing increasing the probability of collisions, repeating send several copies of the same message, as well as increasing the delay. Hence, a new mechanism in route discovery stage and in caching the routes in DSR algorithm according to the node's location in the network and the direction of the broadcast is proposed for better performance especially in terms of delay as well as redundant packets rate. The implementation of proposed algorithms showed positive results in terms of delay, overhead, and improve the performance of MANETs in general.

  18. A Survey on Temperature-Aware Routing Protocols in Wireless Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sangman Moh

    2013-08-01

    Full Text Available The rapid growth of the elderly population in the world and the rising cost of healthcare impose big issues for healthcare and medical monitoring. A Wireless Body Sensor Network (WBSN is comprised of small sensor nodes attached inside, on or around a human body, the main purpose of which is to monitor the functions and surroundings of the human body. However, the heat generated by the node’s circuitry and antenna could cause damage to the human tissue. Therefore, in designing a routing protocol for WBSNs, it is important to reduce the heat by incorporating temperature into the routing metric. The main contribution of this paper is to survey existing temperature-aware routing protocols that have been proposed for WBSNs. In this paper, we present a brief overview of WBSNs, review the existing routing protocols comparatively and discuss challenging open issues in the design of routing protocols.

  19. A Comparative Study of Wireless Sensor Networks and Their Routing Protocols

    Directory of Open Access Journals (Sweden)

    Subhajit Pal

    2010-11-01

    Full Text Available Recent developments in the area of micro-sensor devices have accelerated advances in the sensor networks field leading to many new protocols specifically designed for wireless sensor networks (WSNs. Wireless sensor networks with hundreds to thousands of sensor nodes can gather information from an unattended location and transmit the gathered data to a particular user, depending on the application. These sensor nodes have some constraints due to their limited energy, storage capacity and computing power. Data are routed from one node to other using different routing protocols. There are a number of routing protocols for wireless sensor networks. In this review article, we discuss the architecture of wireless sensor networks. Further, we categorize the routing protocols according to some key factors and summarize their mode of operation. Finally, we provide a comparative study on these various protocols.

  20. Model-Checking Driven Design of QoS-Based Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Zhi Chen

    2015-01-01

    Full Text Available Accurate and reliable routing protocols with Quality of Service (QoS support determine the mission-critical application efficiency in WSNs. This paper proposes a model-checking design driven framework for designing the QoS-based routing protocols of WSNs, which involves the light-weight design process, the timed automata model, and the alternative QoS verification properties. The accurate feedback of continually model checking in the iterative design process effectively stimulates the parameter tuning of the protocols. We demonstrate the straightforward and modular characteristics of the proposed framework in designing a prototype QoS-based routing protocol. The prototype study shows that the model-checking design framework may complement other design methods and ensure the QoS implementation of the QoS-based routing protocol design for WSNs.

  1. A Comprehensive Survey on Hierarchical-Based Routing Protocols for Mobile Wireless Sensor Networks: Review, Taxonomy, and Future Directions

    Directory of Open Access Journals (Sweden)

    Nabil Sabor

    2017-01-01

    Full Text Available Introducing mobility to Wireless Sensor Networks (WSNs puts new challenges particularly in designing of routing protocols. Mobility can be applied to the sensor nodes and/or the sink node in the network. Many routing protocols have been developed to support the mobility of WSNs. These protocols are divided depending on the routing structure into hierarchical-based, flat-based, and location-based routing protocols. However, the hierarchical-based routing protocols outperform the other routing types in saving energy, scalability, and extending lifetime of Mobile WSNs (MWSNs. Selecting an appropriate hierarchical routing protocol for specific applications is an important and difficult task. Therefore, this paper focuses on reviewing some of the recently hierarchical-based routing protocols that are developed in the last five years for MWSNs. This survey divides the hierarchical-based routing protocols into two broad groups, namely, classical-based and optimized-based routing protocols. Also, we present a detailed classification of the reviewed protocols according to the routing approach, control manner, mobile element, mobility pattern, network architecture, clustering attributes, protocol operation, path establishment, communication paradigm, energy model, protocol objectives, and applications. Moreover, a comparison between the reviewed protocols is investigated in this survey depending on delay, network size, energy-efficiency, and scalability while mentioning the advantages and drawbacks of each protocol. Finally, we summarize and conclude the paper with future directions.

  2. The Application of RPL Routing Protocol in Low Power Wireless Sensor and Lossy Networks

    Directory of Open Access Journals (Sweden)

    Xun Yang

    2014-05-01

    Full Text Available With the continuous development of computer information technology, wireless sensor has been successfully changed the mode of human life, at the same time, as one of the technologies continues to improve the future life, how to better integration with the RPL routing protocols together become one of research focuses in the current climate. This paper start from the wireless sensor network, briefly discusses the concept, followed by systematic exposition of RPL routing protocol developed background, relevant standards, working principle, topology and related terms, and finally explore the RPL routing protocol in wireless sensor low power lossy network applications.

  3. EpSoc: Social-Based Epidemic-Based Routing Protocol in Opportunistic Mobile Social Network

    Directory of Open Access Journals (Sweden)

    Halikul Lenando

    2018-01-01

    Full Text Available In opportunistic networks, the nature of intermittent and disruptive connections degrades the efficiency of routing. Epidemic routing protocol is used as a benchmark for most of routing protocols in opportunistic mobile social networks (OMSNs due to its high message delivery and latency. However, Epidemic incurs high cost in terms of overhead and hop count. In this paper, we propose a hybrid routing protocol called EpSoc which utilizes the Epidemic routing forwarding strategy and exploits an important social feature, that is, degree centrality. Two techniques are used in EpSoc. Messages’ TTL is adjusted based on the degree centrality of nodes, and the message blocking mechanism is used to control replication. Simulation results show that EpSoc increases the delivery ratio and decreases the overhead ratio, the average latency, and the hop counts as compared to Epidemic and Bubble Rap.

  4. A Secure Routing Protocol for Wireless Sensor Networks Considering Secure Data Aggregation

    Directory of Open Access Journals (Sweden)

    Triana Mugia Rahayu

    2015-06-01

    Full Text Available The commonly unattended and hostile deployments of WSNs and their resource-constrained sensor devices have led to an increasing demand for secure energy-efficient protocols. Routing and data aggregation receive the most attention since they are among the daily network routines. With the awareness of such demand, we found that so far there has been no work that lays out a secure routing protocol as the foundation for a secure data aggregation protocol. We argue that the secure routing role would be rendered useless if the data aggregation scheme built on it is not secure. Conversely, the secure data aggregation protocol needs a secure underlying routing protocol as its foundation in order to be effectively optimal. As an attempt for the solution, we devise an energy-aware protocol based on LEACH and ESPDA that combines secure routing protocol and secure data aggregation protocol. We then evaluate its security effectiveness and its energy-efficiency aspects, knowing that there are always trade-off between both.

  5. ABORt: Acknowledgement-Based Opportunistic Routing Protocol for High Data Rate Multichannel WSNs

    Directory of Open Access Journals (Sweden)

    Hamadoun Tall

    2017-10-01

    Full Text Available The ease of deployment and the auto-configuration capabilities of Wireless Sensor Networks (WSNs make them very attractive in different domains like environmental, home automation or heath care applications. The use of multichannel communications in WSNs helps to improve the overall performance of the network. However, in heavy traffic scenarios, routing protocols should be adapted to allow load balancing and to avoid losing data packets due to congestion and queue overflow. In this paper, we present an Acknowledgement-Based Opportunistic Routing (ABORt protocol designed for high data rate multichannel WSNs. It is a low overhead protocol that does not rely on synchronization for control traffic exchange during the operational phase of the network. ABORt is an opportunistic protocol that relies on link layer acknowledgements to disseminate routing metrics, which helps to reduce overhead. The performance of ABORt is evaluated using the Cooja simulator and the obtained results show that ABORt has a high packet delivery ratio with reduced packet end-to-end delay compared to two single channel routing protocols and two multichannel routing protocols that use number of hops and expected transmission count as routing metrics.

  6. Energy neutral protocol based on hierarchical routing techniques for energy harvesting wireless sensor network

    Science.gov (United States)

    Muhammad, Umar B.; Ezugwu, Absalom E.; Ofem, Paulinus O.; Rajamäki, Jyri; Aderemi, Adewumi O.

    2017-06-01

    Recently, researchers in the field of wireless sensor networks have resorted to energy harvesting techniques that allows energy to be harvested from the ambient environment to power sensor nodes. Using such Energy harvesting techniques together with proper routing protocols, an Energy Neutral state can be achieved so that sensor nodes can run perpetually. In this paper, we propose an Energy Neutral LEACH routing protocol which is an extension to the traditional LEACH protocol. The goal of the proposed protocol is to use Gateway node in each cluster so as to reduce the data transmission ranges of cluster head nodes. Simulation results show that the proposed routing protocol achieves a higher throughput and ensure the energy neutral status of the entire network.

  7. Advanced flooding-based routing protocols for underwater sensor networks

    OpenAIRE

    Isufi, E.; Dol, H.; Leus, G.J.T.

    2016-01-01

    Flooding-based protocols are a reliable solution to deliver packets in underwater sensor networks. However, these protocols potentially involve all the nodes in the forwarding process. Thus, the performance and energy efficiency are not optimal. In this work, we propose some advances of a flooding-based protocol with the goal to improve the performance and the energy efficiency. The first idea considers the node position information in order to reduce the number of relays that may apply flood...

  8. Network Coding to Enhance Standard Routing Protocols in Wireless Mesh Networks

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Roetter, Daniel Enrique Lucani; Fitzek, Frank

    2013-01-01

    This paper introduces a design and simulation of a locally optimized network coding protocol, called PlayNCool, for wireless mesh networks. PlayN-Cool is easy to implement and compatible with existing routing protocols and devices. This allows the system to gain from network coding capabilities i...

  9. A Smart Collaborative Routing Protocol for Reliable Data Diffusion in IoT Scenarios.

    Science.gov (United States)

    Ai, Zheng-Yang; Zhou, Yu-Tong; Song, Fei

    2018-06-13

    It is knotty for current routing protocols to meet the needs of reliable data diffusion during the Internet of Things (IoT) deployments. Due to the random placement, limited resources and unattended features of existing sensor nodes, the wireless transmissions are easily exposed to unauthorized users, which becomes a vulnerable area for various malicious attacks, such as wormhole and Sybil attacks. However, the scheme based on geographic location is a suitable candidate to defend against them. This paper is inspired to propose a smart collaborative routing protocol, Geographic energy aware routing and Inspecting Node (GIN), for guaranteeing the reliability of data exchanging. The proposed protocol integrates the directed diffusion routing, Greedy Perimeter Stateless Routing (GPSR), and the inspecting node mechanism. We first discuss current wireless routing protocols from three diverse perspectives (improving transmission rate, shortening transmission range and reducing transmission consumption). Then, the details of GIN, including the model establishment and implementation processes, are presented by means of the theoretical analysis. Through leveraging the game theory, the inspecting node is elected to monitor the network behaviors. Thirdly, we evaluate the network performances, in terms of transmission delay, packet loss ratio, and throughput, between GIN and three traditional schemes (i.e., Flooding, GPSR, and GEAR). The simulation results illustrate that the proposed protocol is able to outperform the others.

  10. Suppressing traffic-driven epidemic spreading by use of the efficient routing protocol

    International Nuclear Information System (INIS)

    Yang, Han-Xin; Wu, Zhi-Xi

    2014-01-01

    Despite extensive work on the interplay between traffic dynamics and epidemic spreading, the control of epidemic spreading by routing strategies has not received adequate attention. In this paper, we study the impact of an efficient routing protocol on epidemic spreading. In the case of infinite node-delivery capacity, where the traffic is free of congestion, we find that that there exist optimal values of routing parameter, leading to the maximal epidemic threshold. This means that epidemic spreading can be effectively controlled by fine tuning the routing scheme. Moreover, we find that an increase in the average network connectivity and the emergence of traffic congestion can suppress the epidemic outbreak. (paper)

  11. Multipath Activity Based Routing Protocol for Mobile ‎Cognitive Radio Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Shereen Omar

    2017-01-01

    Full Text Available Cognitive radio networks improve spectrum utilization by ‎sharing licensed spectrum with cognitive radio devices. In ‎cognitive radio ad hoc networks the routing protocol is one ‎of the most challenging tasks due to the changes in ‎frequency spectrum and the interrupted connectivity ‎caused by the primary user activity. In this paper, a multi‎path activity based routing protocol for cognitive radio ‎network (MACNRP is proposed. The protocol utilizes ‎channel availability and creates multiple node-disjoint ‎routes between the source and destination nodes. The ‎proposed protocol is compared with D2CARP and FTCRP ‎protocols. The performance evaluation is conducted ‎through mathematical analysis and using OPNET ‎simulation. The performance of the proposed protocol ‎achieves an increase in network throughput; besides it ‎decreases the probability of route failure due to node ‎mobility and primary user activity. We have found that the ‎MACNRP scheme results in 50% to 75% reduction in ‎blocking probability and 33% to 78% improvement in ‎network throughput, with a reasonable additional routing ‎overhead and average packet delay. Due to the successful ‎reduction of collision between primary users and ‎cognitive users, the MACNRP scheme results in decreasing ‎the path failure rate by 50% to 87%.‎

  12. Efficient Security Mechanisms for the Border Gateway Routing Protocol

    Science.gov (United States)

    1997-08-22

    Finding Algorithm for Loop- Free Routing. IEEE/ACM Transactions on Networking, 5(1):148{160, Feb. 1997. [7] International Standards Organization. ISO/IEC...Jersey 07974, Feb. 1985. ftp://netlib.att.com/netlib/att/cs/ cstr /117.ps.Z. [16] S. L. Murphy. Presentation in Panel on \\Security Architecture for the

  13. Energy- Efficient Routing Protocols For Wireless Sensor Network A Review

    Directory of Open Access Journals (Sweden)

    Pardeep Kaur

    2017-12-01

    Full Text Available There has been plenty of interest in building and deploying sensor networks. Wireless sensor network is a collection of a large number of small nodes which acts as routers also. These nodes carry very limited power source which is non-rechargeable and non-replaceable which makes energy consumption an significant issue. Energy conservation is a very important issue for prolonging the lifetime of the network. As the sensor nodes act like routers as well the determination of routing technique plays a key role in controlling the consumption of energy. This paper describes the framework of wireless sensor network and the analysis and study of various research work related to Energy Efficient Routing in Wireless Sensor Networks.

  14. Secure energy efficient routing protocol for wireless sensor network

    OpenAIRE

    Das Ayan Kumar; Chaki Rituparna; Dey Kashi Nath

    2016-01-01

    The ease of deployment of economic sensor networks has always been a boon to disaster management applications. However, their vulnerability to a number of security threats makes communication a challenging task. This paper proposes a new routing technique to prevent from both external threats and internal threats like hello flooding, eavesdropping and wormhole attack. In this approach one way hash chain is used to reduce the energy drainage. Level based event driven clustering also helps to s...

  15. A Study on IP Network Recovery through Routing Protocols

    Directory of Open Access Journals (Sweden)

    K. Karthik

    2016-09-01

    Full Text Available Internet has taken major role in our communication infrastructure. Such that requirement of internet availability and reliability has increasing accordingly. The major network failure reasons are failure of node and failure of link among the nodes. This can reduce the performance of major applications in an IP networks. The network recovery should be fast enough so that service interruption of link or node failure. The new path taken by the diverted traffic can be computed either at the time of failures or before failures. These mechanisms are known as Reactive and Proactive protocols respectively. In this paper, we surveyed reactive and proactive protocols mechanisms for IP network recovery.

  16. An Environment-Friendly Multipath Routing Protocol for Underwater Acoustic Sensor Network

    Directory of Open Access Journals (Sweden)

    Yun Li

    2017-01-01

    Full Text Available Underwater Acoustic Sensor Network (UASN is a promising technique by facilitating a wide range of aquatic applications. However, routing scheme in UASN is a challenging task because of the characteristics of the nodes mobility, interruption of link, and interference caused by other underwater acoustic systems such as marine mammals. In order to achieve reliable data delivery in UASN, in this work, we present a disjoint multipath disruption-tolerant routing protocol for UASN (ENMR, which incorporates the Hue, Saturation, and Value color space (HSV model to establish routing paths to greedily forward data packets to sink nodes. ENMR applies the mechanism to maintain the network topology. Simulation results show that, compared with the classic underwater routing protocols named PVBF, ENMR can improve packet delivery ratio and reduce network latency while avoiding introducing additional energy consumption.

  17. Secure energy efficient routing protocol for wireless sensor network

    Directory of Open Access Journals (Sweden)

    Das Ayan Kumar

    2016-03-01

    Full Text Available The ease of deployment of economic sensor networks has always been a boon to disaster management applications. However, their vulnerability to a number of security threats makes communication a challenging task. This paper proposes a new routing technique to prevent from both external threats and internal threats like hello flooding, eavesdropping and wormhole attack. In this approach one way hash chain is used to reduce the energy drainage. Level based event driven clustering also helps to save energy. The simulation results show that the proposed scheme extends network lifetime even when the cluster based wireless sensor network is under attack.

  18. Application of Game Theory Approaches in Routing Protocols for Wireless Networks

    Science.gov (United States)

    Javidi, Mohammad M.; Aliahmadipour, Laya

    2011-09-01

    An important and essential issue for wireless networks is routing protocol design that is a major technical challenge due to the function of the network. Game theory is a powerful mathematical tool that analyzes the strategic interactions among multiple decision makers and the results of researches show that applied game theory in routing protocol lead to improvement the network performance through reduce overhead and motivates selfish nodes to collaborate in the network. This paper presents a review and comparison for typical representatives of routing protocols designed that applied game theory approaches for various wireless networks such as ad hoc networks, mobile ad hoc networks and sensor networks that all of them lead to improve the network performance.

  19. Design and Analysis of Secure Routing Protocol for Wireless Sensor Networks

    Science.gov (United States)

    Wang, Jiong; Zhang, Hua

    2017-09-01

    In recent years, with the development of science and technology and the progress of the times, China's wireless network technology has become increasingly prosperous and it plays an important role in social production and life. In this context, in order to further to enhance the stability of wireless network data transmission and security enhancements, the staff need to focus on routing security and carry out related work. Based on this, this paper analyzes the design of wireless sensor based on secure routing protocol.

  20. DRUG: An Energy-Efficient Data-Centric Routing Protocol for Wireless Sensor Networks

    OpenAIRE

    Sahoo, B. P. S.; Puthal, Deepak

    2014-01-01

    In general, sensor nodes are deployed in left unattended area. In such situation feeding energy to the batteries or replacing the batteries is difficult or even sometimes impossible too. Therefore, prolonging the network lifetime is an important optimization goal in this aspect. In this paper, we propose a new Energy-efficient Datacentric RoUtinG protocol called DRUG. In this paper, we propose an adaptive Data centric approach to find an optimal routing path from source to sink when the senso...

  1. A Survey on the Taxonomy of Cluster-Based Routing Protocols for Homogeneous Wireless Sensor Networks

    Science.gov (United States)

    Naeimi, Soroush; Ghafghazi, Hamidreza; Chow, Chee-Onn; Ishii, Hiroshi

    2012-01-01

    The past few years have witnessed increased interest among researchers in cluster-based protocols for homogeneous networks because of their better scalability and higher energy efficiency than other routing protocols. Given the limited capabilities of sensor nodes in terms of energy resources, processing and communication range, the cluster-based protocols should be compatible with these constraints in either the setup state or steady data transmission state. With focus on these constraints, we classify routing protocols according to their objectives and methods towards addressing the shortcomings of clustering process on each stage of cluster head selection, cluster formation, data aggregation and data communication. We summarize the techniques and methods used in these categories, while the weakness and strength of each protocol is pointed out in details. Furthermore, taxonomy of the protocols in each phase is given to provide a deeper understanding of current clustering approaches. Ultimately based on the existing research, a summary of the issues and solutions of the attributes and characteristics of clustering approaches and some open research areas in cluster-based routing protocols that can be further pursued are provided. PMID:22969350

  2. IMHRP: Improved Multi-Hop Routing Protocol for Wireless Sensor Networks

    Science.gov (United States)

    Huang, Jianhua; Ruan, Danwei; Hong, Yadong; Zhao, Ziming; Zheng, Hong

    2017-10-01

    Wireless sensor network (WSN) is a self-organizing system formed by a large number of low-cost sensor nodes through wireless communication. Sensor nodes collect environmental information and transmit it to the base station (BS). Sensor nodes usually have very limited battery energy. The batteries cannot be charged or replaced. Therefore, it is necessary to design an energy efficient routing protocol to maximize the network lifetime. This paper presents an improved multi-hop routing protocol (IMHRP) for homogeneous networks. In the IMHRP protocol, based on the distances to the BS, the CH nodes are divided into internal CH nodes and external CH nodes. The set-up phase of the protocol is based on the LEACH protocol and the minimum distance between CH nodes are limited to a special constant distance, so a more uniform distribution of CH nodes is achieved. In the steady-state phase, the routes of different CH nodes are created on the basis of the distances between the CH nodes. The energy efficiency of communication can be maximized. The simulation results show that the proposed algorithm can more effectively reduce the energy consumption of each round and prolong the network lifetime compared with LEACH protocol and MHT protocol.

  3. Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks.

    Science.gov (United States)

    Saleem, Kashif; Derhab, Abdelouahid; Orgun, Mehmet A; Al-Muhtadi, Jalal; Rodrigues, Joel J P C; Khalil, Mohammed Sayim; Ali Ahmed, Adel

    2016-03-31

    The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs) composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP) involves an artificial immune system (AIS) that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP) that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2) and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks.

  4. Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks

    Science.gov (United States)

    Saleem, Kashif; Derhab, Abdelouahid; Orgun, Mehmet A.; Al-Muhtadi, Jalal; Rodrigues, Joel J. P. C.; Khalil, Mohammed Sayim; Ali Ahmed, Adel

    2016-01-01

    The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs) composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP) involves an artificial immune system (AIS) that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP) that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2) and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks. PMID:27043572

  5. RELIABLE DYNAMIC SOURCE ROUTING PROTOCOL (RDSRP FOR ENERGY HARVESTING WIRELESS SENSOR NETWORKS

    Directory of Open Access Journals (Sweden)

    B. Narasimhan

    2015-03-01

    Full Text Available Wireless sensor networks (WSNs carry noteworthy pros over traditional communication. Though, unkind and composite environments fake great challenges in the reliability of WSN communications. It is more vital to develop a reliable unipath dynamic source routing protocol (RDSRPl for WSN to provide better quality of service (QoS in energy harvesting wireless sensor networks (EH-WSN. This paper proposes a dynamic source routing approach for attaining the most reliable route in EH-WSNs. Performance evaluation is carried out using NS-2 and throughput and packet delivery ratio are chosen as the metrics.

  6. Prediction Schemes to Enhance the Routing Process in Geographical GPSR Ad Hoc Protocol

    Directory of Open Access Journals (Sweden)

    Raed Saqour

    2007-01-01

    Full Text Available Geographical routing protocols have received a serious attention due to more advantages they have in comparison to the conventional routing protocols. They require information about the physical position of nodes needed to be available. Commonly, each node determines its own position through the use of Global Positioning System (GPS or some other type of positioning service. Greedy Perimeter Stateless Routing (GPSR protocol, which is one of geographical routing protocols, limits the forwarding decision of the packet based on the node's own position, the destination's position and the position of the forwarding node's neighbors. Location information has some inaccuracy depending on the localization system and the environment exists in. This paper aims to study the impact of mobility metrics (beacon interval, and node speed on introducing location information error in GPSR protocol using different mobility models. The effect of these metrics is identified in GPSR as Neighbor Break Link (NBL problem. Based on simulation analysis, mobility prediction schemes are proposed to migrate the observed problem.

  7. UMDR: Multi-Path Routing Protocol for Underwater Ad Hoc Networks with Directional Antenna

    Science.gov (United States)

    Yang, Jianmin; Liu, Songzuo; Liu, Qipei; Qiao, Gang

    2018-01-01

    This paper presents a new routing scheme for underwater ad hoc networks based on directional antennas. Ad hoc networks with directional antennas have become a hot research topic because of space reuse may increase networks capacity. At present, researchers have applied traditional self-organizing routing protocols (such as DSR, AODV) [1] [2] on this type of networks, and the routing scheme is based on the shortest path metric. However, such routing schemes often suffer from long transmission delays and frequent link fragmentation along the intermediate nodes of the selected route. This is caused by a unique feature of directional transmission, often called as “deafness”. In this paper, we take a different approach to explore the advantages of space reuse through multipath routing. This paper introduces the validity of the conventional routing scheme in underwater ad hoc networks with directional antennas, and presents a special design of multipath routing algorithm for directional transmission. The experimental results show a significant performance improvement in throughput and latency.

  8. Analysis of energy efficient routing protocols for implementation of a ubiquitous health system

    Science.gov (United States)

    Kwon, Jongwon; Park, Yongman; Koo, Sangjun; Ayurzana, Odgeral; Kim, Hiesik

    2007-12-01

    The innovative Ubiquitous-Health was born through convergence of medical service, with development of up to date information technologies and ubiquitous IT. The U-Health can be applied to a variety of special situations for managing functions of each medical center efficiently. This paper focuses on estimation of various routing protocols for implementation of U-health monitoring system. In order to facilitate wireless communication over the network, a routing protocol on the network layer is used to establish precise and efficient route between sensor nodes so that information acquired from sensors may be delivered in a timely manner. A route establishment should be considered to minimize overhead, data loss and power consumption because wireless networks for U-health are organized by a large number of sensor nodes which are small in size and have limited processing power, memory and battery life. In this paper a overview of wireless sensor network technologies commonly known is described as well as evaluation of three multi hop routing protocols which are flooding, gossiping and modified low energy adaptive clustering hierarchy(LEACH) for use with these networks using TOSSIM simulator. As a result of evaluation the integrated wireless sensor board was developed in particular. The board is embedded device based on AVR128 porting TinyOS. Also it employs bio sensor measures blood pressure, pulse frequency and ZigBee module for wireless communication. This paper accelerates the digital convergence age through continual research and development of technologies related the U-Health.

  9. SURVEY OF ENERGY COMPETENCE ROUTING PROTOCOL IN UTILIZING AODV IN MANETS (20150471)

    OpenAIRE

    TUSHAR SINGH RAJPUT; RAJ KUMAR PAUL

    2018-01-01

    In MANETs (Mobile unintentional Networks) communication at the mobile nodes will be achieved by mistreatment multihop wireless links. The aim of every protocol, in Associate in Nursing ad-hoc network, is to seek out valid routes between 2 communication nodes.

  10. An Energy Balanced and Lifetime Extended Routing Protocol for Underwater Sensor Networks.

    Science.gov (United States)

    Wang, Hao; Wang, Shilian; Zhang, Eryang; Lu, Luxi

    2018-05-17

    Energy limitation is an adverse problem in designing routing protocols for underwater sensor networks (UWSNs). To prolong the network lifetime with limited battery power, an energy balanced and efficient routing protocol, called energy balanced and lifetime extended routing protocol (EBLE), is proposed in this paper. The proposed EBLE not only balances traffic loads according to the residual energy, but also optimizes data transmissions by selecting low-cost paths. Two phases are operated in the EBLE data transmission process: (1) candidate forwarding set selection phase and (2) data transmission phase. In candidate forwarding set selection phase, nodes update candidate forwarding nodes by broadcasting the position and residual energy level information. The cost value of available nodes is calculated and stored in each sensor node. Then in data transmission phase, high residual energy and relatively low-cost paths are selected based on the cost function and residual energy level information. We also introduce detailed analysis of optimal energy consumption in UWSNs. Numerical simulation results on a variety of node distributions and data load distributions prove that EBLE outperforms other routing protocols (BTM, BEAR and direct transmission) in terms of network lifetime and energy efficiency.

  11. A Comparison of Routing Protocol for WSNs: Redundancy Based Approach A Comparison of Routing Protocol for WSNs: Redundancy Based Approach

    Directory of Open Access Journals (Sweden)

    Anand Prakash

    2014-03-01

    Full Text Available Wireless Sensor Networks (WSNs with their dynamic applications gained a tremendous attention of researchers. Constant monitoring of critical situations attracted researchers to utilize WSNs at vast platforms. The main focus in WSNs is to enhance network localization as much as one could, for efficient and optimal utilization of resources. Different approaches based upon redundancy are proposed for optimum functionality. Localization is always related with redundancy of sensor nodes deployed at remote areas for constant and fault tolerant monitoring. In this work, we propose a comparison of classic flooding and the gossip protocol for homogenous networks which enhances stability and throughput quiet significantly.  

  12. Prediction based Greedy Perimeter Stateless Routing Protocol for Vehicular Self-organizing Network

    Science.gov (United States)

    Wang, Chunlin; Fan, Quanrun; Chen, Xiaolin; Xu, Wanjin

    2018-03-01

    PGPSR (Prediction based Greedy Perimeter Stateless Routing) is based on and extended the GPSR protocol to adapt to the high speed mobility of the vehicle auto organization network (VANET) and the changes in the network topology. GPSR is used in the VANET network environment, the network loss rate and throughput are not ideal, even cannot work. Aiming at the problems of the GPSR, the proposed PGPSR routing protocol, it redefines the hello and query packet structure, in the structure of the new node speed and direction information, which received the next update before you can take advantage of its speed and direction to predict the position of node and new network topology, select the right the next hop routing and path. Secondly, the update of the outdated node information of the neighbor’s table is deleted in time. The simulation experiment shows the performance of PGPSR is better than that of GPSR.

  13. PERFORMANCE ANALYSIS OF DSR ROUTING PROTOCOL UNDER ENERGY BASED SELFISH ATTACK IN MOBILE AD HOC NETWORKS

    Directory of Open Access Journals (Sweden)

    T.V.P.Sundararajan

    2010-06-01

    Full Text Available Mobile Ad hoc Networks (MANETs rely on the cooperation of all participating nodes to provide the fundamental operations such as routing and data forwarding. However, due to the open structure and scarcely available battery-based energy, node misbehaviors may exist.[1]. One such routing misbehavior is that some selfish nodes will participate in the route discovery and maintenance processes but refuse to forward data packets. This paper pointed out Energy based selfish nodes (EBSN where these selfish nodes tend to use the network but do not cooperate, saving battery life for their own communications [2],[3]. We present a simulation study of the effects of Energy based selfish nodes (EBSN on DSR routing protocol and its impact over network performance in terms of throughput and delay of a mobile ad hoc network where a defined percentage of nodes were misbehaving.

  14. An authenticated encrypted routing protocol against attacks in mobile ad-hoc networks

    Directory of Open Access Journals (Sweden)

    C.C. Suma

    2017-01-01

    Full Text Available Mobile Ad hoc Network is stated as a cluster that contains Digital data terminals and they are furnished with the wireless transceivers which are able to communicate with each other with no need of any fixed architecture or concentrated authority. Security is one of the major issues in MANETs because of vast applications such as Military Battlefields, emergency and rescue operations[10]. In order to provide anonymous communications and to identify the malicious nodes in MANETs, many authors have proposed different secure routing protocols but each protocol have their own advantages and disadvantages. In MANTE’s each and every node in the communicating network functions like router and transmits the packets among the networking nodes for the purpose of communication[11]. Sometimes nodes may be attacked by the malicious nodes or the legitimate node will be caught by foemen there by controlling and preventing the nodes to perform the assigned task or nodes may be corrupted due to loss of energy. So, due to these drawbacks securing the network under the presence of adversaries is an important thing. The existing protocols were designed with keeping anonymity and the identification of vicious nodes in the network as the main goal. For providing better security, the anonymity factors such as Unidentifiability and Unlinkability must be fully satisfied[1]. Many anonymous routing schemes that concentrate on achieving anonymity are proposed in the past decade and they provides the security at different levels and also provides the privacy protection that is of different cost. In this paper we consider a protocol called Authenticated Secure Routing Protocol proposed which provides both security & anonymity. Anonymity is achieved in this protocol using Group signature. Over all by using this protocol performance in terms of throughput as well as the packet dropping rate is good compared to the other living protocols.

  15. Self-Adaptive Contention Aware Routing Protocol for Intermittently Connected Mobile Networks

    KAUST Repository

    Elwhishi, Ahmed

    2013-07-01

    This paper introduces a novel multicopy routing protocol, called Self-Adaptive Utility-based Routing Protocol (SAURP), for Delay Tolerant Networks (DTNs) that are possibly composed of a vast number of devices in miniature such as smart phones of heterogeneous capacities in terms of energy resources and buffer spaces. SAURP is characterized by the ability of identifying potential opportunities for forwarding messages to their destinations via a novel utility function-based mechanism, in which a suite of environment parameters, such as wireless channel condition, nodal buffer occupancy, and encounter statistics, are jointly considered. Thus, SAURP can reroute messages around nodes experiencing high-buffer occupancy, wireless interference, and/or congestion, while taking a considerably small number of transmissions. The developed utility function in SAURP is proved to be able to achieve optimal performance, which is further analyzed via a stochastic modeling approach. Extensive simulations are conducted to verify the developed analytical model and compare the proposed SAURP with a number of recently reported encounter-based routing approaches in terms of delivery ratio, delivery delay, and the number of transmissions required for each message delivery. The simulation results show that SAURP outperforms all the counterpart multicopy encounter-based routing protocols considered in the study.

  16. Self-Adaptive Contention Aware Routing Protocol for Intermittently Connected Mobile Networks

    KAUST Repository

    Elwhishi, Ahmed; Ho, Pin-Han; Naik, K.; Shihada, Basem

    2013-01-01

    This paper introduces a novel multicopy routing protocol, called Self-Adaptive Utility-based Routing Protocol (SAURP), for Delay Tolerant Networks (DTNs) that are possibly composed of a vast number of devices in miniature such as smart phones of heterogeneous capacities in terms of energy resources and buffer spaces. SAURP is characterized by the ability of identifying potential opportunities for forwarding messages to their destinations via a novel utility function-based mechanism, in which a suite of environment parameters, such as wireless channel condition, nodal buffer occupancy, and encounter statistics, are jointly considered. Thus, SAURP can reroute messages around nodes experiencing high-buffer occupancy, wireless interference, and/or congestion, while taking a considerably small number of transmissions. The developed utility function in SAURP is proved to be able to achieve optimal performance, which is further analyzed via a stochastic modeling approach. Extensive simulations are conducted to verify the developed analytical model and compare the proposed SAURP with a number of recently reported encounter-based routing approaches in terms of delivery ratio, delivery delay, and the number of transmissions required for each message delivery. The simulation results show that SAURP outperforms all the counterpart multicopy encounter-based routing protocols considered in the study.

  17. An Improved PRoPHET Routing Protocol in Delay Tolerant Network

    Directory of Open Access Journals (Sweden)

    Seung Deok Han

    2015-01-01

    Full Text Available In delay tolerant network (DTN, an end-to-end path is not guaranteed and packets are delivered from a source node to a destination node via store-carry-forward based routing. In DTN, a source node or an intermediate node stores packets in buffer and carries them while it moves around. These packets are forwarded to other nodes based on predefined criteria and finally are delivered to a destination node via multiple hops. In this paper, we improve the dissemination speed of PRoPHET (probability routing protocol using history of encounters and transitivity protocol by employing epidemic protocol for disseminating message m, if forwarding counter and hop counter values are smaller than or equal to the threshold values. The performance of the proposed protocol was analyzed from the aspect of delivery probability, average delay, and overhead ratio. Numerical results show that the proposed protocol can improve the delivery probability, average delay, and overhead ratio of PRoPHET protocol by appropriately selecting the threshold forwarding counter and threshold hop counter values.

  18. Cost-Effective Encryption-Based Autonomous Routing Protocol for Efficient and Secure Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kashif Saleem

    2016-03-01

    Full Text Available The deployment of intelligent remote surveillance systems depends on wireless sensor networks (WSNs composed of various miniature resource-constrained wireless sensor nodes. The development of routing protocols for WSNs is a major challenge because of their severe resource constraints, ad hoc topology and dynamic nature. Among those proposed routing protocols, the biology-inspired self-organized secure autonomous routing protocol (BIOSARP involves an artificial immune system (AIS that requires a certain amount of time to build up knowledge of neighboring nodes. The AIS algorithm uses this knowledge to distinguish between self and non-self neighboring nodes. The knowledge-building phase is a critical period in the WSN lifespan and requires active security measures. This paper proposes an enhanced BIOSARP (E-BIOSARP that incorporates a random key encryption mechanism in a cost-effective manner to provide active security measures in WSNs. A detailed description of E-BIOSARP is presented, followed by an extensive security and performance analysis to demonstrate its efficiency. A scenario with E-BIOSARP is implemented in network simulator 2 (ns-2 and is populated with malicious nodes for analysis. Furthermore, E-BIOSARP is compared with state-of-the-art secure routing protocols in terms of processing time, delivery ratio, energy consumption, and packet overhead. The findings show that the proposed mechanism can efficiently protect WSNs from selective forwarding, brute-force or exhaustive key search, spoofing, eavesdropping, replaying or altering of routing information, cloning, acknowledgment spoofing, HELLO flood attacks, and Sybil attacks.

  19. SACFIR: SDN-Based Application-Aware Centralized Adaptive Flow Iterative Reconfiguring Routing Protocol for WSNs.

    Science.gov (United States)

    Aslam, Muhammad; Hu, Xiaopeng; Wang, Fan

    2017-12-13

    Smart reconfiguration of a dynamic networking environment is offered by the central control of Software-Defined Networking (SDN). Centralized SDN-based management architectures are capable of retrieving global topology intelligence and decoupling the forwarding plane from the control plane. Routing protocols developed for conventional Wireless Sensor Networks (WSNs) utilize limited iterative reconfiguration methods to optimize environmental reporting. However, the challenging networking scenarios of WSNs involve a performance overhead due to constant periodic iterative reconfigurations. In this paper, we propose the SDN-based Application-aware Centralized adaptive Flow Iterative Reconfiguring (SACFIR) routing protocol with the centralized SDN iterative solver controller to maintain the load-balancing between flow reconfigurations and flow allocation cost. The proposed SACFIR's routing protocol offers a unique iterative path-selection algorithm, which initially computes suitable clustering based on residual resources at the control layer and then implements application-aware threshold-based multi-hop report transmissions on the forwarding plane. The operation of the SACFIR algorithm is centrally supervised by the SDN controller residing at the Base Station (BS). This paper extends SACFIR to SDN-based Application-aware Main-value Centralized adaptive Flow Iterative Reconfiguring (SAMCFIR) to establish both proactive and reactive reporting. The SAMCFIR transmission phase enables sensor nodes to trigger direct transmissions for main-value reports, while in the case of SACFIR, all reports follow computed routes. Our SDN-enabled proposed models adjust the reconfiguration period according to the traffic burden on sensor nodes, which results in heterogeneity awareness, load-balancing and application-specific reconfigurations of WSNs. Extensive experimental simulation-based results show that SACFIR and SAMCFIR yield the maximum scalability, network lifetime and stability

  20. SACFIR: SDN-Based Application-Aware Centralized Adaptive Flow Iterative Reconfiguring Routing Protocol for WSNs

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam

    2017-12-01

    Full Text Available Smart reconfiguration of a dynamic networking environment is offered by the central control of Software-Defined Networking (SDN. Centralized SDN-based management architectures are capable of retrieving global topology intelligence and decoupling the forwarding plane from the control plane. Routing protocols developed for conventional Wireless Sensor Networks (WSNs utilize limited iterative reconfiguration methods to optimize environmental reporting. However, the challenging networking scenarios of WSNs involve a performance overhead due to constant periodic iterative reconfigurations. In this paper, we propose the SDN-based Application-aware Centralized adaptive Flow Iterative Reconfiguring (SACFIR routing protocol with the centralized SDN iterative solver controller to maintain the load-balancing between flow reconfigurations and flow allocation cost. The proposed SACFIR’s routing protocol offers a unique iterative path-selection algorithm, which initially computes suitable clustering based on residual resources at the control layer and then implements application-aware threshold-based multi-hop report transmissions on the forwarding plane. The operation of the SACFIR algorithm is centrally supervised by the SDN controller residing at the Base Station (BS. This paper extends SACFIR to SDN-based Application-aware Main-value Centralized adaptive Flow Iterative Reconfiguring (SAMCFIR to establish both proactive and reactive reporting. The SAMCFIR transmission phase enables sensor nodes to trigger direct transmissions for main-value reports, while in the case of SACFIR, all reports follow computed routes. Our SDN-enabled proposed models adjust the reconfiguration period according to the traffic burden on sensor nodes, which results in heterogeneity awareness, load-balancing and application-specific reconfigurations of WSNs. Extensive experimental simulation-based results show that SACFIR and SAMCFIR yield the maximum scalability, network lifetime

  1. Performance Analysis of AODV Routing Protocol for Wireless Sensor Network based Smart Metering

    International Nuclear Information System (INIS)

    Farooq, Hasan; Jung, Low Tang

    2013-01-01

    Today no one can deny the need for Smart Grid and it is being considered as of utmost importance to upgrade outdated electric infrastructure to cope with the ever increasing electric load demand. Wireless Sensor Network (WSN) is considered a promising candidate for internetworking of smart meters with the gateway using mesh topology. This paper investigates the performance of AODV routing protocol for WSN based smart metering deployment. Three case studies are presented to analyze its performance based on four metrics of (i) Packet Delivery Ratio, (ii) Average Energy Consumption of Nodes (iii) Average End-End Delay and (iv) Normalized Routing Load.

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

    Science.gov (United States)

    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.

  3. A comprehensive survey of energy-aware routing protocols in wireless body area sensor networks.

    Science.gov (United States)

    Effatparvar, Mehdi; Dehghan, Mehdi; Rahmani, Amir Masoud

    2016-09-01

    Wireless body area sensor network is a special purpose wireless sensor network that, employing wireless sensor nodes in, on, or around the human body, makes it possible to measure biological parameters of a person for specific applications. One of the most fundamental concerns in wireless body sensor networks is accurate routing in order to send data promptly and properly, and therefore overcome some of the challenges. Routing protocols for such networks are affected by a large number of factors including energy, topology, temperature, posture, the radio range of sensors, and appropriate quality of service in sensor nodes. Since energy is highly important in wireless body area sensor networks, and increasing the network lifetime results in benefiting greatly from sensor capabilities, improving routing performance with reduced energy consumption presents a major challenge. This paper aims to study wireless body area sensor networks and the related routing methods. It also presents a thorough, comprehensive review of routing methods in wireless body area sensor networks from the perspective of energy. Furthermore, different routing methods affecting the parameter of energy will be classified and compared according to their advantages and disadvantages. In this paper, fundamental concepts of wireless body area sensor networks are provided, and then the advantages and disadvantages of these networks are investigated. Since one of the most fundamental issues in wireless body sensor networks is to perform routing so as to transmit data precisely and promptly, we discuss the same issue. As a result, we propose a classification of the available relevant literature with respect to the key challenge of energy in the routing process. With this end in view, all important papers published between 2000 and 2015 are classified under eight categories including 'Mobility-Aware', 'Thermal-Aware', 'Restriction of Location and Number of Relays', 'Link-aware', 'Cluster- and Tree

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

    Directory of Open Access Journals (Sweden)

    Zhou Jingjing

    2014-01-01

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

  5. L2-LBMT: A Layered Load Balance Routing Protocol for underwater multimedia data transmission

    Science.gov (United States)

    Lv, Ze; Tang, Ruichun; Tao, Ye; Sun, Xin; Xu, Xiaowei

    2017-12-01

    Providing highly efficient underwater transmission of mass multimedia data is challenging due to the particularities of the underwater environment. Although there are many schemes proposed to optimize the underwater acoustic network communication protocols, from physical layer, data link layer, network layer to transport layer, the existing routing protocols for underwater wireless sensor network (UWSN) still cannot well deal with the problems in transmitting multimedia data because of the difficulties involved in high energy consumption, low transmission reliability or high transmission delay. It prevents us from applying underwater multimedia data to real-time monitoring of marine environment in practical application, especially in emergency search, rescue operation and military field. Therefore, the inefficient transmission of marine multimedia data has become a serious problem that needs to be solved urgently. In this paper, A Layered Load Balance Routing Protocol (L2-LBMT) is proposed for underwater multimedia data transmission. In L2-LBMT, we use layered and load-balance Ad Hoc Network to transmit data, and adopt segmented data reliable transfer (SDRT) protocol to improve the data transport reliability. And a 3-node variant of tornado (3-VT) code is also combined with the Ad Hoc Network to transmit little emergency data more quickly. The simulation results show that the proposed protocol can balance energy consumption of each node, effectively prolong the network lifetime and reduce transmission delay of marine multimedia data.

  6. Energy-Efficient Cluster Based Routing Protocol in Mobile Ad Hoc Networks Using Network Coding

    Directory of Open Access Journals (Sweden)

    Srinivas Kanakala

    2014-01-01

    Full Text Available In mobile ad hoc networks, all nodes are energy constrained. In such situations, it is important to reduce energy consumption. In this paper, we consider the issues of energy efficient communication in MANETs using network coding. Network coding is an effective method to improve the performance of wireless networks. COPE protocol implements network coding concept to reduce number of transmissions by mixing the packets at intermediate nodes. We incorporate COPE into cluster based routing protocol to further reduce the energy consumption. The proposed energy-efficient coding-aware cluster based routing protocol (ECCRP scheme applies network coding at cluster heads to reduce number of transmissions. We also modify the queue management procedure of COPE protocol to further improve coding opportunities. We also use an energy efficient scheme while selecting the cluster head. It helps to increase the life time of the network. We evaluate the performance of proposed energy efficient cluster based protocol using simulation. Simulation results show that the proposed ECCRP algorithm reduces energy consumption and increases life time of the network.

  7. Analysis of MD5 authentication in various routing protocols using simulation tools

    Science.gov (United States)

    Dinakaran, M.; Darshan, K. N.; Patel, Harsh

    2017-11-01

    Authentication being an important paradigm of security and Computer Networks require secure paths to make the flow of the data even more secure through some security protocols. So MD-5(Message Digest 5) helps in providing data integrity to the data being sent through it and authentication to the network devices. This paper gives a brief introduction to the MD-5, simulation of the networks by including MD-5 authentication using various routing protocols like OSPF, EIGRP and RIPv2. GNS3 is being used to simulate the scenarios. Analysis of the MD-5 authentication is done in the later sections of the paper.

  8. Energy Threshold-based Cluster Head Rotation for Routing Protocol in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Hadi Raheem Ali

    2018-05-01

    Full Text Available Energy efficiency represents a fundamental issue in WSNs, since the network lifetime period entirely depends on the energy of sensor nodes, which are usually battery-operated. In this article, an unequal clustering-based routing protocol has been suggested, where parameters of energy, distance, and density are involved in the cluster head election. Besides, the sizes of clusters are unequal according to distance, energy, and density. Furthermore, the cluster heads are not changed every round unless the residual energy reaches a specific threshold of energy. The outcomes of the conducted simulation confirmed that the performance of the suggested protocol achieves improvement in energy efficiency.

  9. Performance Analysis of Routing Protocols in Ad-hoc and Sensor Networking Environments

    Directory of Open Access Journals (Sweden)

    L. Gavrilovska

    2009-06-01

    Full Text Available Ad-hoc and sensor networks are becoming an increasingly popular wireless networking concepts lately. This paper analyzes and compares prominent routing schemes in these networking environments. The knowledge obtained can serve users to better understand short range wireless network solutions thus leading to options for implementation in various scenarios. In addition, it should aid researchers develop protocol improvements reliable for the technologies of interest.

  10. Energy-Efficient Cluster Based Routing Protocol in Mobile Ad Hoc Networks Using Network Coding

    OpenAIRE

    Srinivas Kanakala; Venugopal Reddy Ananthula; Prashanthi Vempaty

    2014-01-01

    In mobile ad hoc networks, all nodes are energy constrained. In such situations, it is important to reduce energy consumption. In this paper, we consider the issues of energy efficient communication in MANETs using network coding. Network coding is an effective method to improve the performance of wireless networks. COPE protocol implements network coding concept to reduce number of transmissions by mixing the packets at intermediate nodes. We incorporate COPE into cluster based routing proto...

  11. Performance Analysis of the Enhanced DSR Routing Protocol for the Short Time Disconnected MANET to the OPNET Modeler

    Directory of Open Access Journals (Sweden)

    PAPAJ Ján

    2013-05-01

    Full Text Available Disconnected mobile ad-hoc networks (MANET are very important areas of the research. In this article, the performance analysis of the enhanced dynamic source routing protocol (OPP_DSR is introduced. This modification enables the routing process in the case when there are no connections to other mobile nodes. It also will enable the routing mechanisms when the routes, selected by routing mechanisms, are disconnected for some time. Disconnection can be for a short time and standard routing protocol DSR cannot reflect on this situation.The main idea is based on opportunistic forwarding where the nodes not only forward data but it's stored in the cache during long time. The network parameters throughput, routing load and are analysed.

  12. A Game Theory-Based Obstacle Avoidance Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Shujun Bi

    2011-09-01

    Full Text Available The obstacle avoidance problem in geographic forwarding is an important issue for location-based routing in wireless sensor networks. The presence of an obstacle leads to several geographic routing problems such as excessive energy consumption and data congestion. Obstacles are hard to avoid in realistic environments. To bypass obstacles, most routing protocols tend to forward packets along the obstacle boundaries. This leads to a situation where the nodes at the boundaries exhaust their energy rapidly and the obstacle area is diffused. In this paper, we introduce a novel routing algorithm to solve the obstacle problem in wireless sensor networks based on a game-theory model. Our algorithm forms a concave region that cannot forward packets to achieve the aim of improving the transmission success rate and decreasing packet transmission delays. We consider the residual energy, out-degree and forwarding angle to determine the forwarding probability and payoff function of forwarding candidates. This achieves the aim of load balance and reduces network energy consumption. Simulation results show that based on the average delivery delay, energy consumption and packet delivery ratio performances our protocol is superior to other traditional schemes.

  13. An Efficient Data-Gathering Routing Protocol for Underwater Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Nadeem Javaid

    2015-11-01

    Full Text Available Most applications of underwater wireless sensor networks (UWSNs demand reliable data delivery over a longer period in an efficient and timely manner. However, the harsh and unpredictable underwater environment makes routing more challenging as compared to terrestrial WSNs. Most of the existing schemes deploy mobile sensors or a mobile sink (MS to maximize data gathering. However, the relatively high deployment cost prevents their usage in most applications. Thus, this paper presents an autonomous underwater vehicle (AUV-aided efficient data-gathering (AEDG routing protocol for reliable data delivery in UWSNs. To prolong the network lifetime, AEDG employs an AUV for data collection from gateways and uses a shortest path tree (SPT algorithm while associating sensor nodes with the gateways. The AEDG protocol also limits the number of associated nodes with the gateway nodes to minimize the network energy consumption and to prevent the gateways from overloading. Moreover, gateways are rotated with the passage of time to balance the energy consumption of the network. To prevent data loss, AEDG allows dynamic data collection at the AUV depending on the limited number of member nodes that are associated with each gateway. We also develop a sub-optimal elliptical trajectory of AUV by using a connected dominating set (CDS to further facilitate network throughput maximization. The performance of the AEDG is validated via simulations, which demonstrate the effectiveness of AEDG in comparison to two existing UWSN routing protocols in terms of the selected performance metrics.

  14. An Efficient Data-Gathering Routing Protocol for Underwater Wireless Sensor Networks.

    Science.gov (United States)

    Javaid, Nadeem; Ilyas, Naveed; Ahmad, Ashfaq; Alrajeh, Nabil; Qasim, Umar; Khan, Zahoor Ali; Liaqat, Tayyaba; Khan, Majid Iqbal

    2015-11-17

    Most applications of underwater wireless sensor networks (UWSNs) demand reliable data delivery over a longer period in an efficient and timely manner. However, the harsh and unpredictable underwater environment makes routing more challenging as compared to terrestrial WSNs. Most of the existing schemes deploy mobile sensors or a mobile sink (MS) to maximize data gathering. However, the relatively high deployment cost prevents their usage in most applications. Thus, this paper presents an autonomous underwater vehicle (AUV)-aided efficient data-gathering (AEDG) routing protocol for reliable data delivery in UWSNs. To prolong the network lifetime, AEDG employs an AUV for data collection from gateways and uses a shortest path tree (SPT) algorithm while associating sensor nodes with the gateways. The AEDG protocol also limits the number of associated nodes with the gateway nodes to minimize the network energy consumption and to prevent the gateways from overloading. Moreover, gateways are rotated with the passage of time to balance the energy consumption of the network. To prevent data loss, AEDG allows dynamic data collection at the AUV depending on the limited number of member nodes that are associated with each gateway. We also develop a sub-optimal elliptical trajectory of AUV by using a connected dominating set (CDS) to further facilitate network throughput maximization. The performance of the AEDG is validated via simulations, which demonstrate the effectiveness of AEDG in comparison to two existing UWSN routing protocols in terms of the selected performance metrics.

  15. ADAPTIVE CLUSTER BASED ROUTING PROTOCOL WITH ANT COLONY OPTIMIZATION FOR MOBILE AD-HOC NETWORK IN DISASTER AREA

    Directory of Open Access Journals (Sweden)

    Enrico Budianto

    2012-07-01

    Full Text Available In post-disaster rehabilitation efforts, the availability of telecommunication facilities takes important role. However, the process to improve telecommunication facilities in disaster area is risky if it is done by humans. Therefore, a network method that can work efficiently, effectively, and capable to reach the widest possible area is needed. This research introduces a cluster-based routing protocol named Adaptive Cluster Based Routing Protocol (ACBRP equipped by Ant Colony Optimization method, and its implementation in a simulator developed by author. After data analysis and statistical tests, it can be concluded that routing protocol ACBRP performs better than AODV and DSR routing protocol. Pada upaya rehabilitasi pascabencana, ketersediaan fasilitas telekomunikasi memiliki peranan yang sangat penting. Namun, proses untuk memperbaiki fasilitas telekomunikasi di daerah bencana memiliki resiko jika dilakukan oleh manusia. Oleh karena itu, metode jaringan yang dapat bekerja secara efisien, efektif, dan mampu mencapai area seluas mungkin diperlukan. Penelitian ini memperkenalkan sebuah protokol routing berbasis klaster bernama Adaptive Cluster Based Routing Protocol (ACBRP, yang dilengkapi dengan metode Ant Colony Optimization, dan diimplementasikan pada simulator yang dikembangkan penulis. Setelah data dianalisis dan dilakukan uji statistik, disimpulkan bahwa protokol routing ACBRP beroperasi lebih baik daripada protokol routing AODV maupun DSR.

  16. A lightweight neighbor-info-based routing protocol for no-base-station taxi-call system.

    Science.gov (United States)

    Zhu, Xudong; Wang, Jinhang; Chen, Yunchao

    2014-01-01

    Since the quick topology change and short connection duration, the VANET has had unstable routing and wireless signal quality. This paper proposes a kind of lightweight routing protocol-LNIB for call system without base station, which is applicable to the urban taxis. LNIB maintains and predicts neighbor information dynamically, thus finding the reliable path between the source and the target. This paper describes the protocol in detail and evaluates the performance of this protocol by simulating under different nodes density and speed. The result of evaluation shows that the performance of LNIB is better than AODV which is a classic protocol in taxi-call scene.

  17. A routing protocol based on energy and link quality for Internet of Things applications.

    Science.gov (United States)

    Machado, Kássio; Rosário, Denis; Cerqueira, Eduardo; Loureiro, Antonio A F; Neto, Augusto; Souza, José Neuman de

    2013-02-04

    The Internet of Things (IoT) is attracting considerable attention from the universities, industries, citizens and governments for applications, such as healthcare, environmental monitoring and smart buildings. IoT enables network connectivity between smart devices at all times, everywhere, and about everything. In this context, Wireless Sensor Networks (WSNs) play an important role in increasing the ubiquity of networks with smart devices that are low-cost and easy to deploy. However, sensor nodes are restricted in terms of energy, processing and memory. Additionally, low-power radios are very sensitive to noise, interference and multipath distortions. In this context, this article proposes a routing protocol based on Routing by Energy and Link quality (REL) for IoT applications. To increase reliability and energy-efficiency, REL selects routes on the basis of a proposed end-to-end link quality estimator mechanism, residual energy and hop count. Furthermore, REL proposes an event-driven mechanism to provide load balancing and avoid the premature energy depletion of nodes/networks. Performance evaluations were carried out using simulation and testbed experiments to show the impact and benefits of REL in small and large-scale networks. The results show that REL increases the network lifetime and services availability, as well as the quality of service of IoT applications. It also provides an even distribution of scarce network resources and reduces the packet loss rate, compared with the performance of well-known protocols.

  18. A Routing Protocol Based on Energy and Link Quality for Internet of Things Applications

    Directory of Open Access Journals (Sweden)

    Antonio A. F. Loureiro

    2013-02-01

    Full Text Available The Internet of Things (IoT is attracting considerable attention from the universities, industries, citizens and governments for applications, such as healthcare, environmental monitoring and smart buildings. IoT enables network connectivity between smart devices at all times, everywhere, and about everything. In this context, Wireless Sensor Networks (WSNs play an important role in increasing the ubiquity of networks with smart devices that are low-cost and easy to deploy. However, sensor nodes are restricted in terms of energy, processing and memory. Additionally, low-power radios are very sensitive to noise, interference and multipath distortions. In this context, this article proposes a routing protocol based on Routing by Energy and Link quality (REL for IoT applications. To increase reliability and energy-efficiency, REL selects routes on the basis of a proposed end-to-end link quality estimator mechanism, residual energy and hop count. Furthermore, REL proposes an event-driven mechanism to provide load balancing and avoid the premature energy depletion of nodes/networks. Performance evaluations were carried out using simulation and testbed experiments to show the impact and benefits of REL in small and large-scale networks. The results show that REL increases the network lifetime and services availability, as well as the quality of service of IoT applications. It also provides an even distribution of scarce network resources and reduces the packet loss rate, compared with the performance of well-known protocols.

  19. A Routing Protocol Based on Energy and Link Quality for Internet of Things Applications

    Science.gov (United States)

    Machado, Kassio; Rosário, Denis; Cerqueira, Eduardo; Loureiro, Antonio A. F.; Neto, Augusto; de Souza, José Neuman

    2013-01-01

    The Internet of Things (IoT) is attracting considerable attention from the universities, industries, citizens and governments for applications, such as healthcare,environmental monitoring and smart buildings. IoT enables network connectivity between smart devices at all times, everywhere, and about everything. In this context, Wireless Sensor Networks (WSNs) play an important role in increasing the ubiquity of networks with smart devices that are low-cost and easy to deploy. However, sensor nodes are restricted in terms of energy, processing and memory. Additionally, low-power radios are very sensitive to noise, interference and multipath distortions. In this context, this article proposes a routing protocol based on Routing by Energy and Link quality (REL) for IoT applications. To increase reliability and energy-efficiency, REL selects routes on the basis of a proposed end-to-end link quality estimator mechanism, residual energy and hop count. Furthermore, REL proposes an event-driven mechanism to provide load balancing and avoid the premature energy depletion of nodes/networks. Performance evaluations were carried out using simulation and testbed experiments to show the impact and benefits of REL in small and large-scale networks. The results show that REL increases the network lifetime and services availability, as well as the quality of service of IoT applications. It also provides an even distribution of scarce network resources and reduces the packet loss rate, compared with the performance of well-known protocols. PMID:23385410

  20. Routing protocol for wireless quantum multi-hop mesh backbone network based on partially entangled GHZ state

    Science.gov (United States)

    Xiong, Pei-Ying; Yu, Xu-Tao; Zhang, Zai-Chen; Zhan, Hai-Tao; Hua, Jing-Yu

    2017-08-01

    Quantum multi-hop teleportation is important in the field of quantum communication. In this study, we propose a quantum multi-hop communication model and a quantum routing protocol with multihop teleportation for wireless mesh backbone networks. Based on an analysis of quantum multi-hop protocols, a partially entangled Greenberger-Horne-Zeilinger (GHZ) state is selected as the quantum channel for the proposed protocol. Both quantum and classical wireless channels exist between two neighboring nodes along the route. With the proposed routing protocol, quantum information can be transmitted hop by hop from the source node to the destination node. Based on multi-hop teleportation based on the partially entangled GHZ state, a quantum route established with the minimum number of hops. The difference between our routing protocol and the classical one is that in the former, the processes used to find a quantum route and establish quantum channel entanglement occur simultaneously. The Bell state measurement results of each hop are piggybacked to quantum route finding information. This method reduces the total number of packets and the magnitude of air interface delay. The deduction of the establishment of a quantum channel between source and destination is also presented here. The final success probability of quantum multi-hop teleportation in wireless mesh backbone networks was simulated and analyzed. Our research shows that quantum multi-hop teleportation in wireless mesh backbone networks through a partially entangled GHZ state is feasible.

  1. On-Demand Telemetry

    Data.gov (United States)

    National Aeronautics and Space Administration — AFRC has previously investigated the use of Network Based Telemetry. We will be building on that research to enable On-Demand Telemetry. On-Demand Telemetry is a way...

  2. Discrete Particle Swarm Optimization Routing Protocol for Wireless Sensor Networks with Multiple Mobile Sinks.

    Science.gov (United States)

    Yang, Jin; Liu, Fagui; Cao, Jianneng; Wang, Liangming

    2016-07-14

    Mobile sinks can achieve load-balancing and energy-consumption balancing across the wireless sensor networks (WSNs). However, the frequent change of the paths between source nodes and the sinks caused by sink mobility introduces significant overhead in terms of energy and packet delays. To enhance network performance of WSNs with mobile sinks (MWSNs), we present an efficient routing strategy, which is formulated as an optimization problem and employs the particle swarm optimization algorithm (PSO) to build the optimal routing paths. However, the conventional PSO is insufficient to solve discrete routing optimization problems. Therefore, a novel greedy discrete particle swarm optimization with memory (GMDPSO) is put forward to address this problem. In the GMDPSO, particle's position and velocity of traditional PSO are redefined under discrete MWSNs scenario. Particle updating rule is also reconsidered based on the subnetwork topology of MWSNs. Besides, by improving the greedy forwarding routing, a greedy search strategy is designed to drive particles to find a better position quickly. Furthermore, searching history is memorized to accelerate convergence. Simulation results demonstrate that our new protocol significantly improves the robustness and adapts to rapid topological changes with multiple mobile sinks, while efficiently reducing the communication overhead and the energy consumption.

  3. Multi-Gateway-Based Energy Holes Avoidance Routing Protocol for WSN

    Directory of Open Access Journals (Sweden)

    Rohini Sharma

    2016-04-01

    Full Text Available In wireless sensor networks (WSNs, efficient energy conservation is required to prolong the lifetime of the network. In this work, we have given emphasis on balanced energy consumption and energy holes avoidance. This paper proposes a multi-gateway-based approach to reduce the transmission distance between the sender and the sink node. The area to be monitored is divided into regions and gateway nodes are deployed at optimal positions. We have designed a transmission scheme, in which sensors in the sink region communicate directly to the sink, sensors in the gateway region communicate directly to the gateway, and sensors in the cluster region transmit their data directly to their respective cluster head which transmits data to the gateway in its region. If the distance between a cluster head and the sink is less than the distance between the cluster head and the gateway node, the cluster head transmits data to the sink instead of the gateway node. We have compared the proposed protocol with Low-Energy Adaptive Clustering Hierarchy (LEACH, Gateway Based Energy Aware Multi-Hop Routing (M-GEAR, and Gateway Based Stable Election Protocol (GSEP protocols. The protocol performs better than other protocols in terms of throughput, stability period, lifetime, residual energy, and the packet transmitted to the sink.

  4. Modeling and Simulation of a Novel Relay Node Based Secure Routing Protocol Using Multiple Mobile Sink for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Madhumathy Perumal

    2015-01-01

    Full Text Available Data gathering and optimal path selection for wireless sensor networks (WSN using existing protocols result in collision. Increase in collision further increases the possibility of packet drop. Thus there is a necessity to eliminate collision during data aggregation. Increasing the efficiency is the need of the hour with maximum security. This paper is an effort to come up with a reliable and energy efficient WSN routing and secure protocol with minimum delay. This technique is named as relay node based secure routing protocol for multiple mobile sink (RSRPMS. This protocol finds the rendezvous point for optimal transmission of data using a “splitting tree” technique in tree-shaped network topology and then to determine all the subsequent positions of a sink the “Biased Random Walk” model is used. In case of an event, the sink gathers the data from all sources, when they are in the sensing range of rendezvous point. Otherwise relay node is selected from its neighbor to transfer packets from rendezvous point to sink. A symmetric key cryptography is used for secure transmission. The proposed relay node based secure routing protocol for multiple mobile sink (RSRPMS is experimented and simulation results are compared with Intelligent Agent-Based Routing (IAR protocol to prove that there is increase in the network lifetime compared with other routing protocols.

  5. Improvement over the OLSR Routing Protocol in Mobile Ad Hoc Networks by Eliminating the Unnecessary Loops

    OpenAIRE

    Shahram Behzad; Reza Fotohi; Shahram Jamali

    2013-01-01

    Mobile ad hoc networks are type of wireless networks in which any kind of infrastructure is not used, i.e. there are no infrastructures such as routers or switches or anything else on the network that can be used to support the network structure and the nodes has mobility. The purpose of this paper is to provide a better quality of the package delivery rate and the throughput, that is in need of powerful routing protocol standards, which can guarantee delivering of the packages to destination...

  6. Power Management Based Grid Routing Protocol for IEEE 802.11 Based MANET

    Institute of Scientific and Technical Information of China (English)

    XU Li; ZHENG Bao-yu; YANG Zhen

    2004-01-01

    MANET ( Mobile Ad Hoc Network ) is a collection of wireless mobile nodes forming a temporary communication network without the aid of any established infrastructure or centralized administration. The lifetime of a MANET depends on the battery resources of the mobile nodes. So energy consumption may one of important design criterions for MANET. With changing the idle model to sleep model in the grid environment, this paper proposes a new energy-aware routing protocol. Performance simulation results show that the proposed strategy can dynamic balance the traffic load inside the whole network, extend the lifetime of a MANET, and without decreasing the throughput ratio.

  7. 移动Ad Hoc网络路由协议综述%A Survey of Routing Protocols for Mobile Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    张顺亮; 叶澄清; 李方敏

    2003-01-01

    A review of current research about routing protocols for mobile Ad Hoc networks is made. Based on classifying of them, the characteristic, the strength and the weakness of these protocols are evaluated respectively. Then some crucial strategies to improve the existing routing protocols are proposed. Besides, a frame of new routing protocol for Ad Hoc networks is put forward. Finally, open issues that still need investigation are listed.

  8. QoS and energy aware cooperative routing protocol for wildfire monitoring wireless sensor networks.

    Science.gov (United States)

    Maalej, Mohamed; Cherif, Sofiane; Besbes, Hichem

    2013-01-01

    Wireless sensor networks (WSN) are presented as proper solution for wildfire monitoring. However, this application requires a design of WSN taking into account the network lifetime and the shadowing effect generated by the trees in the forest environment. Cooperative communication is a promising solution for WSN which uses, at each hop, the resources of multiple nodes to transmit its data. Thus, by sharing resources between nodes, the transmission quality is enhanced. In this paper, we use the technique of reinforcement learning by opponent modeling, optimizing a cooperative communication protocol based on RSSI and node energy consumption in a competitive context (RSSI/energy-CC), that is, an energy and quality-of-service aware-based cooperative communication routing protocol. Simulation results show that the proposed algorithm performs well in terms of network lifetime, packet delay, and energy consumption.

  9. Performance analysis and implementation of proposed mechanism for detection and prevention of security attacks in routing protocols of vehicular ad-hoc network (VANET

    Directory of Open Access Journals (Sweden)

    Parul Tyagi

    2017-07-01

    Full Text Available Next-generation communication networks have become widely popular as ad-hoc networks, broadly categorized as the mobile nodes based on mobile ad-hoc networks (MANET and the vehicular nodes based vehicular ad-hoc networks (VANET. VANET is aimed at maintaining safety to vehicle drivers by begin autonomous communication with the nearby vehicles. Each vehicle in the ad-hoc network performs as an intelligent mobile node characterized by high mobility and formation of dynamic networks. The ad-hoc networks are decentralized dynamic networks that need efficient and secure communication requirements due to the vehicles being persistently in motion. These networks are more susceptible to various attacks like Warm Hole attacks, denial of service attacks and Black Hole Attacks. The paper is a novel attempt to examine and investigate the security features of the routing protocols in VANET, applicability of AODV (Ad hoc On Demand protocol to detect and tackle a particular category of network attacks, known as the Black Hole Attacks. A new algorithm is proposed to enhance the security mechanism of AODV protocol and to introduce a mechanism to detect Black Hole Attacks and to prevent the network from such attacks in which source node stores all route replies in a look up table. This table stores the sequences of all route reply, arranged in ascending order using PUSH and POP operations. The priority is calculated based on sequence number and discard the RREP having presumably very high destination sequence number. The result show that proposed algorithm for detection and prevention of Black Hole Attack increases security in Intelligent Transportation System (ITS and reduces the effect of malicious node in the VANET. NCTUNs simulator is used in this research work.

  10. A Routing Protocol Based on Received Signal Strength for Underwater Wireless Sensor Networks (UWSNs

    Directory of Open Access Journals (Sweden)

    Meiju Li

    2017-11-01

    Full Text Available Underwater wireless sensor networks (UWSNs are featured by long propagation delay, limited energy, narrow bandwidth, high BER (Bit Error Rate and variable topology structure. These features make it very difficult to design a short delay and high energy-efficiency routing protocol for UWSNs. In this paper, a routing protocol independent of location information is proposed based on received signal strength (RSS, which is called RRSS. In RRSS, a sensor node firstly establishes a vector from the node to a sink node; the length of the vector indicates the RSS of the beacon signal (RSSB from the sink node. A node selects the next-hop along the vector according to RSSB and the RSS of a hello packet (RSSH. The node nearer to the vector has higher priority to be a candidate next-hop. To avoid data packets being delivered to the neighbor nodes in a void area, a void-avoiding algorithm is introduced. In addition, residual energy is considered when selecting the next-hop. Meanwhile, we establish mathematic models to analyze the robustness and energy efficiency of RRSS. Lastly, we conduct extensive simulations, and the simulation results show RRSS can save energy consumption and decrease end-to-end delay.

  11. Fundamental Lifetime Mechanisms in Routing Protocols for Wireless Sensor Networks: A Survey and Open Issues

    Science.gov (United States)

    Eslaminejad, Mohammadreza; Razak, Shukor Abd

    2012-01-01

    Wireless sensor networks basically consist of low cost sensor nodes which collect data from environment and relay them to a sink, where they will be subsequently processed. Since wireless nodes are severely power-constrained, the major concern is how to conserve the nodes' energy so that network lifetime can be extended significantly. Employing one static sink can rapidly exhaust the energy of sink neighbors. Furthermore, using a non-optimal single path together with a maximum transmission power level may quickly deplete the energy of individual nodes on the route. This all results in unbalanced energy consumption through the sensor field, and hence a negative effect on the network lifetime. In this paper, we present a comprehensive taxonomy of the various mechanisms applied for increasing the network lifetime. These techniques, whether in the routing or cross-layer area, fall within the following types: multi-sink, mobile sink, multi-path, power control and bio-inspired algorithms, depending on the protocol operation. In this taxonomy, special attention has been devoted to the multi-sink, power control and bio-inspired algorithms, which have not yet received much consideration in the literature. Moreover, each class covers a variety of the state-of-the-art protocols, which should provide ideas for potential future works. Finally, we compare these mechanisms and discuss open research issues. PMID:23202008

  12. Safety of adenosine stress myocardial perfusion imaging by a one-route infusion protocol

    International Nuclear Information System (INIS)

    Kawai, Yuko; Kishino, Koh

    2006-01-01

    When adenosine stress testing is performed, a vein is generally accessed in each arm. To determine whether the one-route infusion protocol, that is, infusion via one upper arm vein, is safe, myocardial perfusion imaging was performed during adenosine stress testing in patients with angina pectoris. Sixty-six consecutive patients (43 men, 68±11 years of age) with suspected coronary artery disease were enrolled in this study. For the stress test, adenosine was injected at 120 μg/kg/min for 6 minutes. Systolic blood pressure, diastolic blood pressure, and heart rate did not show any significant changes after injection of the adenosine and radioisotope (RI) tracer. Adverse events during infusion of the adenosine were seen in 42 (64%) patients and included chest discomfort/oppression in 17 (26%) and dyspnea/throat discomfort in 15 (23%). On the other hand, adverse events just after infusion of the RI tracer occurred in 5 (8%) patients and included chest oppression in 2 (3%) and dyspnea in 1 (2%). Almost all adverse events disappeared quickly without treatment. Therefore, we concluded that adenosine stress myocardial perfusion imaging using a one-route infusion protocol is safe and useful to do for patients unable to secure veins in both arms. (author)

  13. Data-Based Energy Efficient Clustered Routing Protocol for Wireless Sensors Networks – Tabuk Flood Monitoring System Case Study

    Directory of Open Access Journals (Sweden)

    Ammar Babiker

    2017-10-01

    Full Text Available Energy efficiency has been considered as the most important issue in wireless sensor networks. As in many applications, wireless sensors are scattered in a wide harsh area, where the battery replacement or charging will be quite difficult and it is the most important challenge. Therefore, the design of energy saving mechanism becomes mandatory in most recent research. In this paper, a new energy efficient clustered routing protocol is proposed: the proposed protocol is based on analyzing the data collected from the sensors in a base-station. Based on this analysis the cluster head will be selected as the one with the most useful data. Then, a variable time slot is specified to each sensor to minimize the transmission of repetitive and un-useful data. The proposed protocol Data-Based Energy Efficient Clustered Routing Protocol for Wireless Sensors Networks (DCRP was compared with the famous energy efficient LEACH protocol and also with one of the recent energy efficient routing protocols named Position Responsive Routing Protocol (PRRP. DCRP has been used in monitoring the floods in Tabuk area –Saudi Arabia. It shows comparatively better results.

  14. A Multipath Routing Protocol Based on Clustering and Ant Colony Optimization for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2010-05-01

    Full Text Available For monitoring burst events in a kind of reactive wireless sensor networks (WSNs, a multipath routing protocol (MRP based on dynamic clustering and ant colony optimization (ACO is proposed.. Such an approach can maximize the network lifetime and reduce the energy consumption. An important attribute of WSNs is their limited power supply, and therefore some metrics (such as energy consumption of communication among nodes, residual energy, path length were considered as very important criteria while designing routing in the MRP. Firstly, a cluster head (CH is selected among nodes located in the event area according to some parameters, such as residual energy. Secondly, an improved ACO algorithm is applied in the search for multiple paths between the CH and sink node. Finally, the CH dynamically chooses a route to transmit data with a probability that depends on many path metrics, such as energy consumption. The simulation results show that MRP can prolong the network lifetime, as well as balance of energy consumption among nodes and reduce the average energy consumption effectively.

  15. ENERGY EFFICIENT ROUTING PROTOCOLS FOR WIRELESS AD HOC NETWORKS – A SURVEY

    Directory of Open Access Journals (Sweden)

    K. Sankar

    2012-06-01

    Full Text Available Reducing energy consumption, primarily with the goal of extending the lifetime of battery-powered devices, has emerged as a fundamental challenge in wireless communication. The performance of the medium access control (MAC scheme not only has a fairly significant end-result on the behaviour of the routing approach employed, but also on the energy consumption of the wireless network interface card (NIC. We investigate the inadequacies of the MAC schemes designed for ad hoc wireless networks in the context of power awareness herein. The topology changes due to uncontrollable factors such as node mobility, weather, interference, noise, as well as on controllable parameters such as transmission power and antenna direction results in significant amount of energy loss. Controlling rapid topology changes by minimizing the maximum transmission power used in ad hoc wireless networks, while still maintaining networks connectivity can prolong battery life and hence network lifetime considerably. In addition, we systematically explore the potential energy consumption pitfalls of non–power-based and power based routing schemes. We suggest a thorough energy-based performance survey of energy aware routing protocols for wireless mobile ad-hoc networks. We also present the statistical performance metrics measured by our simulations.

  16. Sink-to-Sink Coordination Framework Using RPL: Routing Protocol for Low Power and Lossy Networks

    Directory of Open Access Journals (Sweden)

    Meer M. Khan

    2016-01-01

    Full Text Available RPL (Routing Protocol for low power and Lossy networks is recommended by Internet Engineering Task Force (IETF for IPv6-based LLNs (Low Power and Lossy Networks. RPL uses a proactive routing approach and each node always maintains an active path to the sink node. Sink-to-sink coordination defines syntax and semantics for the exchange of any network defined parameters among sink nodes like network size, traffic load, mobility of a sink, and so forth. The coordination allows sink to learn about the network condition of neighboring sinks. As a result, sinks can make coordinated decision to increase/decrease their network size for optimizing over all network performance in terms of load sharing, increasing network lifetime, and lowering end-to-end latency of communication. Currently, RPL does not provide any coordination framework that can define message exchange between different sink nodes for enhancing the network performance. In this paper, a sink-to-sink coordination framework is proposed which utilizes the periodic route maintenance messages issued by RPL to exchange network status observed at a sink with its neighboring sinks. The proposed framework distributes network load among sink nodes for achieving higher throughputs and longer network’s life time.

  17. CENTERA: A Centralized Trust-Based Efficient Routing Protocol with Authentication for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ayman Tajeddine

    2015-02-01

    Full Text Available In this paper, we present CENTERA, a CENtralized Trust-based Efficient Routing protocol with an appropriate authentication scheme for wireless sensor networks (WSN. CENTERA utilizes the more powerful base station (BS to gather minimal neighbor trust information from nodes and calculate the best routes after isolating different types of “bad” nodes. By periodically accumulating these simple local observations and approximating the nodes’ battery lives, the BS draws a global view of the network, calculates three quality metrics—maliciousness, cooperation, and compatibility—and evaluates the Data Trust and Forwarding Trust values of each node. Based on these metrics, the BS isolates “bad”, “misbehaving” or malicious nodes for a certain period, and put some nodes on probation. CENTERA increases the node’s bad/probation level with repeated “bad” behavior, and decreases it otherwise. Then it uses a very efficient method to distribute the routing information to “good” nodes. Based on its target environment, and if required, CENTERA uses an authentication scheme suitable for severely constrained nodes, ranging from the symmetric RC5 for safe environments under close administration, to pairing-based cryptography (PBC for hostile environments with a strong attacker model. We simulate CENTERA using TOSSIM and verify its correctness and show some energy calculations.

  18. CENTERA: A Centralized Trust-Based Efficient Routing Protocol with Authentication for Wireless Sensor Networks †

    Science.gov (United States)

    Tajeddine, Ayman; Kayssi, Ayman; Chehab, Ali; Elhajj, Imad; Itani, Wassim

    2015-01-01

    In this paper, we present CENTERA, a CENtralized Trust-based Efficient Routing protocol with an appropriate authentication scheme for wireless sensor networks (WSN). CENTERA utilizes the more powerful base station (BS) to gather minimal neighbor trust information from nodes and calculate the best routes after isolating different types of “bad” nodes. By periodically accumulating these simple local observations and approximating the nodes' battery lives, the BS draws a global view of the network, calculates three quality metrics—maliciousness, cooperation, and compatibility—and evaluates the Data Trust and Forwarding Trust values of each node. Based on these metrics, the BS isolates “bad”, “misbehaving” or malicious nodes for a certain period, and put some nodes on probation. CENTERA increases the node's bad/probation level with repeated “bad” behavior, and decreases it otherwise. Then it uses a very efficient method to distribute the routing information to “good” nodes. Based on its target environment, and if required, CENTERA uses an authentication scheme suitable for severely constrained nodes, ranging from the symmetric RC5 for safe environments under close administration, to pairing-based cryptography (PBC) for hostile environments with a strong attacker model. We simulate CENTERA using TOSSIM and verify its correctness and show some energy calculations. PMID:25648712

  19. CENTERA: a centralized trust-based efficient routing protocol with authentication for wireless sensor networks.

    Science.gov (United States)

    Tajeddine, Ayman; Kayssi, Ayman; Chehab, Ali; Elhajj, Imad; Itani, Wassim

    2015-02-02

    In this paper, we present CENTERA, a CENtralized Trust-based Efficient Routing protocol with an appropriate authentication scheme for wireless sensor networks (WSN). CENTERA utilizes the more powerful base station (BS) to gather minimal neighbor trust information from nodes and calculate the best routes after isolating different types of "bad" nodes. By periodically accumulating these simple local observations and approximating the nodes' battery lives, the BS draws a global view of the network, calculates three quality metrics-maliciousness, cooperation, and compatibility-and evaluates the Data Trust and Forwarding Trust values of each node. Based on these metrics, the BS isolates "bad", "misbehaving" or malicious nodes for a certain period, and put some nodes on probation. CENTERA increases the node's bad/probation level with repeated "bad" behavior, and decreases it otherwise. Then it uses a very efficient method to distribute the routing information to "good" nodes. Based on its target environment, and if required, CENTERA uses an authentication scheme suitable for severely constrained nodes, ranging from the symmetric RC5 for safe environments under close administration, to pairing-based cryptography (PBC) for hostile environments with a strong attacker model. We simulate CENTERA using TOSSIM and verify its correctness and show some energy calculations.

  20. DOW-PR DOlphin and Whale Pods Routing Protocol for Underwater Wireless Sensor Networks (UWSNs).

    Science.gov (United States)

    Wadud, Zahid; Ullah, Khadem; Hussain, Sajjad; Yang, Xiaodong; Qazi, Abdul Baseer

    2018-05-12

    Underwater Wireless Sensor Networks (UWSNs) have intrinsic challenges that include long propagation delays, high mobility of sensor nodes due to water currents, Doppler spread, delay variance, multipath, attenuation and geometric spreading. The existing Weighting Depth and Forwarding Area Division Depth Based Routing (WDFAD-DBR) protocol considers the weighting depth of the two hops in order to select the next Potential Forwarding Node (PFN). To improve the performance of WDFAD-DBR, we propose DOlphin and Whale Pod Routing protocol (DOW-PR). In this scheme, we divide the transmission range into a number of transmission power levels and at the same time select the next PFNs from forwarding and suppressed zones. In contrast to WDFAD-DBR, our scheme not only considers the packet upward advancement, but also takes into account the number of suppressed nodes and number of PFNs at the first and second hops. Consequently, reasonable energy reduction is observed while receiving and transmitting packets. Moreover, our scheme also considers the hops count of the PFNs from the sink. In the absence of PFNs, the proposed scheme will select the node from the suppressed region for broadcasting and thus ensures minimum loss of data. Besides this, we also propose another routing scheme (whale pod) in which multiple sinks are placed at water surface, but one sink is embedded inside the water and is physically connected with the surface sink through high bandwidth connection. Simulation results show that the proposed scheme has high Packet Delivery Ratio (PDR), low energy tax, reduced Accumulated Propagation Distance (APD) and increased the network lifetime.

  1. LOTIR: A Routing Protocol for Multi-hop V-to-I Communication Using Local Traffic Information

    Directory of Open Access Journals (Sweden)

    Kun-chan Lan

    2012-08-01

    Full Text Available Vehicular Ad Hoc Network (VANET is an emerging technology that can be applied to safety, transport efficiency, or infotainment applications for roads and highways. However, due to its unique features, such as dynamic mobility patterns and uneven distributions of vehicles, VANET faces many challenging research issues for robust data dissemination in the network. Many routing protocols have been proposed for VANET in the past few years, and the idea of utilizing a navigation system to assist the routing protocol for selecting the next best forwarder has become increasingly popular. However, it might not be realistic to assume that every vehicle is equipped with a navigation system. In addition, due to privacy concerns, drivers might not want to reveal their planned routes to other cars. In this work, we propose a new routing protocol, called LOTIR (LOcal Traffic Information Routing, that relies on only local traffic information and does not require the assistance of a navigation system. LOTIR is a DTN-based routing protocol that utilizes the car-following theory and traffic light information to decide the next carrier to forward the data to. We implement LOTIR in NS-2, and our results show that it can achieve similar performance as prior work which depends on the availability of global network topology information.

  2. Enhancement of Adaptive Cluster Hierarchical Routing Protocol using Distance and Energy for Wireless Sensor Networks

    International Nuclear Information System (INIS)

    Nawar, N.M.; Soliman, S.E.; Kelash, H.M.; Ayad, N.M.

    2014-01-01

    The application of wireless networking is widely used in nuclear applications. This includes reactor control and fire dedication system. This paper is devoted to the application of this concept in the intrusion system of the Radioisotope Production Facility (RPF) of the Egyptian Atomic Energy Authority. This includes the tracking, monitoring and control components of this system. The design and implementation of wireless sensor networks has become a hot area of research due to the extensive use of sensor networks to enable applications that connect the physical world to the virtual world [1-2]. The original LEACH is named a communication protocol (clustering-based); the extended LEACH’s stochastic cluster head selection algorithm by a deterministic component. Depending on the network configuration an increase of network lifetime can be accomplished [3]. The proposed routing mechanisms after enhancement divide the nodes into clusters. A cluster head performs its task which is considerably more energy-intensive than the rest of the nodes inside sensor network. So, nodes rotate tasks at different rounds between a cluster head and other sensors throughout the lifetime of the network to balance the energy dissipation [4-5].The performance improvement when using routing protocol after enhancement of the algorithm which takes into consideration the distance and the remaining energy for choosing the cluster head by obtains from the advertise message. Network Simulator (Ns2 simulator) is used to prove that LEACH after enhancement performs better than the original LEACH protocol in terms of Average Energy, Network Life Time, Delay, Throughput and Overhead.

  3. Performance of Implementation IBR-DTN and Batman-Adv Routing Protocol in Wireless Mesh Networks

    Directory of Open Access Journals (Sweden)

    Herman Yuliandoko

    2016-03-01

    Full Text Available Wireless mesh networks is a network which has high mobility and flexibility network. In Wireless mesh networks nodes are free to move and able to automatically build a network connection with other nodes. High mobility, heterogeneous condition and intermittent network connectivity cause data packets drop during wireless communication and it becomes a problem in the wireless mesh networks. This condition can happen because wireless mesh networks use connectionless networking type such as IP protocol which it is not tolerant to delay. To solve this condition it is needed a technology to keep data packets when the network is disconnect. Delay tolerant technology is a technology that provides store and forward mechanism and it can prevent packet data dropping during communication. In our research, we proposed a test bed wireless mesh networks implementation by using proactive routing protocol and combining with delay tolerant technology. We used Batman-adv routing protocol and IBR-DTN on our research. We measured some particular performance aspect of networking such as packet loss, delay, and throughput of the network. We identified that delay tolerant could keep packet data from dropping better than current wireless mesh networks in the intermittent network condition. We also proved that IBR-DTN and Batman-adv could run together on the wireless mesh networks. In The experiment throughput test result of IBR-DTN was higher than Current TCP on the LoS (Line of Side and on environment with obstacle. Keywords: Delay Tolerant, IBR-DTN, Wireless Mesh, Batman-adv, Performance

  4. Self-Adaptive Context Aware Routing Protocol for Unicast Communication in Delay and Tolerant Network

    Directory of Open Access Journals (Sweden)

    Yunbo Chen

    2014-05-01

    Full Text Available At present, most of research works in mobile network focus on the network overhead of the known path which exists between the sender and the receiver. However, the trend of the current practical application demands is becoming increasingly distributed and decentralized. The Delay and Tolerant Network (DTN just comes out of such background of the conflicts between them. The DTN could effectively eliminate the gap between the mobile network and the practical application demands. In this paper, a Self-Adaptive Context Aware Routing Protocol (SACARP for the unicast communication in delay and tolerant networks is presented. Meanwhile, according to the real-time context information of DTN, the Kalman filter theory is introduced to predict the information state of mobility for the optional message ferrying node, and then gives the optimal selection strategy of the message ferrying nodes. The simulation experiments have shown that, compared to the familiar single- copy and multi-copy protocols, the SACARP proposed in this paper has better transmission performance and stability, especially when the network is free, the protocol would keep a good performance with fewer connections and less buffer space.

  5. Design and Analysis of QoS Routing Framework integrated with OLSR protocol for Multimedia Traffic in Mobile Adhoc Networks

    Directory of Open Access Journals (Sweden)

    S. Soni

    2017-06-01

    Full Text Available MANETs (Mobile Ad-hoc Networks is the self organizing wireless structure of mobile hosts. Wireless media is used for communication in MANETs. Considering the developing requirements for multimedia and real-time traffic applications in real world, QoS (Quality-of-Service support is essential in MANETs. But most of the characteristics of MANETs make QoS support a difficult problem. It is challenging to support QoS routing in MANET due to dynamic behavior and mobility of the hosts. The OLSR (Optimized Link State Routing protocol can be efficiently used in MANETs to provide QoS routing because of its dynamic MPR (Multi Point Relay selection criteria and proactive nature. In this paper, a design of QoS routing framework integrated with OLSR protocol is proposed and also analyzed using network simulator. Proposed QoS framework combines a bandwidth estimation algorithm with explicit resource reservation, QoS routing and connection admission control (CAC. OLSR protocol is extended for QoS framework to solve performance issues related to node mobility using cross layer approach. Results after simulation conclude about efficiency of the proposed QoS routing framework.

  6. Optimising social information by game theory and ant colony method to enhance routing protocol in opportunistic networks

    Directory of Open Access Journals (Sweden)

    Chander Prabha

    2016-09-01

    Full Text Available The data loss and disconnection of nodes are frequent in the opportunistic networks. The social information plays an important role in reducing the data loss because it depends on the connectivity of nodes. The appropriate selection of next hop based on social information is critical for improving the performance of routing in opportunistic networks. The frequent disconnection problem is overcome by optimising the social information with Ant Colony Optimization method which depends on the topology of opportunistic network. The proposed protocol is examined thoroughly via analysis and simulation in order to assess their performance in comparison with other social based routing protocols in opportunistic network under various parameters settings.

  7. Probabilistic Location-based Routing Protocol for Mobile Wireless Sensor Networks with Intermittent Communication

    Directory of Open Access Journals (Sweden)

    Sho KUMAGAI

    2015-02-01

    Full Text Available In a sensor network, sensor data messages reach the nearest stationary sink node connected to the Internet by wireless multihop transmissions. Recently, various mobile sensors are available due to advances of robotics technologies and communication technologies. A location based message-by-message routing protocol, such as Geographic Distance Routing (GEDIR is suitable for such mobile wireless networks; however, it is required for each mobile wireless sensor node to know the current locations of all its neighbor nodes. On the other hand, various intermittent communication methods for a low power consumption requirement have been proposed for wireless sensor networks. Intermittent Receiver-driven Data Transmission (IRDT is one of the most efficient methods; however, it is difficult to combine the location based routing and the intermittent communication. In order to solve this problem, this paper proposes a probabilistic approach IRDT-GEDIR with the help of one of the solutions of the secretaries problem. Here, each time a neighbor sensor node wakes up from its sleep mode, an intermediate sensor node determines whether it forwards its buffered sensor data messages to it or not based on an estimation of achieved pseudo speed of the messages. Simulation experiments show that IRDT-GEDIR achieves higher pseudo speed of sensor data message transmissions and shorter transmission delay than achieves shorter transmission delay than the two naive combinations of IRDT and GEDIR in sensor networks with mobile sensor nodes and a stationary sink node. In addition, the guideline of the estimated numbers of the neighbor nodes of each intermediate sensor node is provided based on the results of the simulation experiments to apply the probabilistic approach IRDT-GEDIR.

  8. GeoVanet: A Routing Protocol for Query Processing in Vehicular Networks

    Directory of Open Access Journals (Sweden)

    Thierry Delot

    2011-01-01

    Full Text Available In a vehicular ad hoc network (VANET, cars can exchange information by using short-range wireless communications. Along with the opportunities offered by vehicular networks, a number of challenges also arise. In particular, most works so far have focused on a push model, where potentially useful data are pushed towards vehicles. The use of pull models, that would allow users to send queries to a set of cars in order to find the desired information, has not been studied in depth. The main challenge for pull models is the difficulty to route the different results towards the query originator in a highly dynamic network where the nodes move very quickly. To solve this issue, we propose GeoVanet, an anonymous and non-intrusive geographic routing protocol which ensures that the sender of a query can get a consistent answer. Our goal is to ensure that the user will be able to retrieve the query results within a bounded time. To prove the effectiveness of GeoVanet, an extensive experimental evaluation has been performed, that proves the interest of the proposal for both rural and urban areas. It shows that up to 80% of the available query results are delivered to the user.

  9. An Energy Centric Cluster-Based Routing Protocol for Wireless Sensor Networks.

    Science.gov (United States)

    Hosen, A S M Sanwar; Cho, Gi Hwan

    2018-05-11

    Clustering is an effective way to prolong the lifetime of a wireless sensor network (WSN). The common approach is to elect cluster heads to take routing and controlling duty, and to periodically rotate each cluster head's role to distribute energy consumption among nodes. However, a significant amount of energy dissipates due to control messages overhead, which results in a shorter network lifetime. This paper proposes an energy-centric cluster-based routing mechanism in WSNs. To begin with, cluster heads are elected based on the higher ranks of the nodes. The rank is defined by residual energy and average distance from the member nodes. With the role of data aggregation and data forwarding, a cluster head acts as a caretaker for cluster-head election in the next round, where the ranks' information are piggybacked along with the local data sending during intra-cluster communication. This reduces the number of control messages for the cluster-head election as well as the cluster formation in detail. Simulation results show that our proposed protocol saves the energy consumption among nodes and achieves a significant improvement in the network lifetime.

  10. A Survey of Routing Issues and Associated Protocols in Underwater Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Khalid

    2017-01-01

    Full Text Available Underwater wireless sensor networks are a newly emerging wireless technology in which small size sensors with limited energy and limited memory and bandwidth are deployed in deep sea water and various monitoring operations like tactical surveillance, environmental monitoring, and data collection are performed through these tiny sensors. Underwater wireless sensor networks are used for the exploration of underwater resources, oceanographic data collection, flood or disaster prevention, tactical surveillance systems, and unmanned underwater vehicles. Sensor nodes consist of a small memory, a central processing unit, and an antenna. Underwater networks are much different from terrestrial sensor networks as radio waves cannot be used in underwater wireless sensor networks. Acoustic channels are used for communication in deep sea water. Acoustic signals have many limitations, such as limited bandwidth, higher end-to-end delay, network path loss, higher propagation delay, and dynamic topology. Usually, these limitations result in higher energy consumption with a smaller number of packets delivered. The main aim nowadays is to operate sensor nodes having a smaller battery for a longer time in the network. This survey has discussed the state-of-the-art localization based and localization-free routing protocols. Routing associated issues in the area of underwater wireless sensor networks have also been discussed.

  11. Pithy Review on Routing Protocols in Wireless Sensor Networks and Least Routing Time Opportunistic Technique in WSN

    Science.gov (United States)

    Salman Arafath, Mohammed; Rahman Khan, Khaleel Ur; Sunitha, K. V. N.

    2018-01-01

    Nowadays due to most of the telecommunication standard development organizations focusing on using device-to-device communication so that they can provide proximity-based services and add-on services on top of the available cellular infrastructure. An Oppnets and wireless sensor network play a prominent role here. Routing in these networks plays a significant role in fields such as traffic management, packet delivery etc. Routing is a prodigious research area with diverse unresolved issues. This paper firstly focuses on the importance of Opportunistic routing and its concept then focus is shifted to prime aspect i.e. on packet reception ratio which is one of the highest QoS Awareness parameters. This paper discusses the two important functions of routing in wireless sensor networks (WSN) namely route selection using least routing time algorithm (LRTA) and data forwarding using clustering technique. Finally, the simulation result reveals that LRTA performs relatively better than the existing system in terms of average packet reception ratio and connectivity.

  12. Multihopping Multilevel Clustering Heterogeneity-Sensitive Optimized Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam

    2017-01-01

    Full Text Available Effective utilization of energy resources in Wireless Sensor Networks (WSNs has become challenging under uncertain distributed cluster-formation and single-hop intercluster communication capabilities. So, sensor nodes are forced to operate at expensive full rate transmission power level continuously during whole network operation. These challenging network environments experience unwanted phenomena of drastic energy consumption and packet drop. In this paper, we propose an adaptive immune Multihopping Multilevel Clustering (MHMLC protocol that executes a Hybrid Clustering Algorithm (HCA to perform optimal centralized selection of Cluster-Heads (CHs within radius of centrally located Base Station (BS and distributed CHs selection in the rest of network area. HCA of MHMLC also produces optimal intermediate CHs for intercluster multihop communications that develop heterogeneity-aware economical links. This hybrid cluster-formation facilitates the sensors to function at short range transmission power level that enhances link quality and avoids packet drop. The simulation environments produce fair comparison among proposed MHMLC and existing state-of-the-art routing protocols. Experimental results give significant evidence of better performance of the proposed model in terms of network lifetime, stability period, and data delivery ratio.

  13. Effect of variation in active route timeout and my route timeout on the performance of AODV-ETX protocol in mobile adhoc network

    Science.gov (United States)

    Purnomo, A.; Widyawan; Najib, W.; Hartono, R.; Hartatik

    2018-03-01

    Mobile adhoc network (MANET) consists of nodes that are independent. A node can communicate each other without the presence of network infrastructure. A node can act as a transmitter and receiver as well as a router. This research has been variation in active route timeout and my route timeout on the performance of AODV-ETX protocol in MANET. The AODV-ETX protocol is the AODV protocol that uses the ETX metric. Performance testing is done on the static node topology with 5 m x 5 m node grid model where the distance between nodes is 100 m and node topology that consists of 25 nodes moves randomly with a moving speed of 1.38 m/s in an area of 1500 m x 300 m. From the test result, on the static node, AODV protocol-ETX shows optimal performance at a value MRT and ART of 10 s and 15 s, but showed a stable performance in the value of MRT and ART ≥60 s, while in randomly moved node topology shows stable performance in the value of MRT and ART ≥80 s.

  14. Education on Demand

    DEFF Research Database (Denmark)

    Boysen, Lis; Hende, Merete

    2015-01-01

    Dette notat beskriver nogle af resultaterne fra programmet "Education on Demand' i projektet Det erhvervsrettede Uddannelseslaboratorium. Programmet har haft fokus på udfordringer og forandringsbehov i uddannelsesinstitutioner og -systemet. Herunder har det beskæftiget sig særligt med de to temat......Dette notat beskriver nogle af resultaterne fra programmet "Education on Demand' i projektet Det erhvervsrettede Uddannelseslaboratorium. Programmet har haft fokus på udfordringer og forandringsbehov i uddannelsesinstitutioner og -systemet. Herunder har det beskæftiget sig særligt med de...

  15. A General Self-Organized Tree-Based Energy-Balance Routing Protocol for Wireless Sensor Network

    Science.gov (United States)

    Han, Zhao; Wu, Jie; Zhang, Jie; Liu, Liefeng; Tian, Kaiyun

    2014-04-01

    Wireless sensor network (WSN) is a system composed of a large number of low-cost micro-sensors. This network is used to collect and send various kinds of messages to a base station (BS). WSN consists of low-cost nodes with limited battery power, and the battery replacement is not easy for WSN with thousands of physically embedded nodes, which means energy efficient routing protocol should be employed to offer a long-life work time. To achieve the aim, we need not only to minimize total energy consumption but also to balance WSN load. Researchers have proposed many protocols such as LEACH, HEED, PEGASIS, TBC and PEDAP. In this paper, we propose a General Self-Organized Tree-Based Energy-Balance routing protocol (GSTEB) which builds a routing tree using a process where, for each round, BS assigns a root node and broadcasts this selection to all sensor nodes. Subsequently, each node selects its parent by considering only itself and its neighbors' information, thus making GSTEB a dynamic protocol. Simulation results show that GSTEB has a better performance than other protocols in balancing energy consumption, thus prolonging the lifetime of WSN.

  16. Generic DART-MS platform for monitoring the on-demand continuous-flow production of pharmaceuticals: Advancing the quantitative protocol for caffeates in microfluidic biocatalysis.

    Science.gov (United States)

    Xu, Yan; Zhang, Dong-Yang; Meng, Xiang-Yun; Liu, Xi; Sheng, Sheng; Wu, Guo-Hua; Wang, Jun; Wu, Fu-An

    2017-04-15

    Today, continuous processing is regarded as an effective on-demand production technique of pharmaceuticals. Homemade microreactors packed with immobilized lipase under continuous-flow conditions were first applied to tailor the production of high-value caffeic acid phenethyl ester (CAPE) from methyl caffeate (MC) and 2-phenylethanol (PE) in cyclohexane via transesterification; however, this method is challenging due to the lack of a rapid platform for monitoring caffeates in microfluidic biocatalysis. The reactants were directly analyzed using Direct Analysis in Real Time Mass Spectrometry (DART-MS), and the corresponding ionization parameters were investigated. Special ions produced from MC (parent ion m/z 192.87 and product ion m/z 133.44) and CAPE (parent ion m/z 282.93 and product ion m/z 178.87) were determined using DART-MS 2 in the negative ion mode. The peak areas of the select reaction monitoring (SRM) signals were calculated to develop the standard curves for quantitative analyses of the concentration. Reasonable linear regression equations of MC and CAPE were obtained in the range of 3.125-50.000mg/L, with linear coefficients (R 2 ) of 0.9515 and 0.9973, limits of detection (LOD) of 0.005 and 0.003mg/L, limits of quantification (LOQ) of 0.02 and 0.01mg/L, and recovery ranges of 92.50-97.11% and 90.11-97.60%, respectively. The results using DART-MS 2 were in good agreement with those using conventional High-Performance Liquid Chromatography with a UV detector (HPLC-UV) and were successfully applied to monitor the kinetics constants and mass transfer coefficients in a continuous-flow packed bed microreactor. Thus, the DART-MS 2 method is an efficient tool for analyzing caffeates in microfluidic biocatalysis with limited sample preparation and short operating time. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. On using multiple routing metrics with destination sequenced distance vector protocol for MultiHop wireless ad hoc networks

    Science.gov (United States)

    Mehic, M.; Fazio, P.; Voznak, M.; Partila, P.; Komosny, D.; Tovarek, J.; Chmelikova, Z.

    2016-05-01

    A mobile ad hoc network is a collection of mobile nodes which communicate without a fixed backbone or centralized infrastructure. Due to the frequent mobility of nodes, routes connecting two distant nodes may change. Therefore, it is not possible to establish a priori fixed paths for message delivery through the network. Because of its importance, routing is the most studied problem in mobile ad hoc networks. In addition, if the Quality of Service (QoS) is demanded, one must guarantee the QoS not only over a single hop but over an entire wireless multi-hop path which may not be a trivial task. In turns, this requires the propagation of QoS information within the network. The key to the support of QoS reporting is QoS routing, which provides path QoS information at each source. To support QoS for real-time traffic one needs to know not only minimum delay on the path to the destination but also the bandwidth available on it. Therefore, throughput, end-to-end delay, and routing overhead are traditional performance metrics used to evaluate the performance of routing protocol. To obtain additional information about the link, most of quality-link metrics are based on calculation of the lost probabilities of links by broadcasting probe packets. In this paper, we address the problem of including multiple routing metrics in existing routing packets that are broadcasted through the network. We evaluate the efficiency of such approach with modified version of DSDV routing protocols in ns-3 simulator.

  18. A Localization Based Cooperative Routing Protocol for Underwater Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Nadeem Javaid

    2017-01-01

    Full Text Available Localization is one of the major aspects in underwater wireless sensor networks (UWSNs. Therefore, it is important to know the accurate position of the sensor node in large scale applications like disaster prevention, tactical surveillance, and monitoring. Due to the inefficiency of the global positioning system (GPS in UWSN, it is very difficult to localize a node in underwater environment compared to terrestrial networks. To minimize the localization error and enhance the localization coverage of the network, two routing protocols are proposed; the first one is mobile autonomous underwater vehicle (MobiL-AUV and the second one is cooperative MobiL (CO-MobiL. In MobiL-AUV, AUVs are deployed and equipped with GPS and act as reference nodes. These reference nodes are used to localize all the nonlocalized ordinary sensor nodes in order to reduce the localization error and maximize the network coverage. CO-MobiL is presented in order to improve the network throughput by using the maximal ratio combining (MRC as diversity technique which combines both signals, received from the source and received from the relay at the destination. It uses amplify-and-forward (AF mechanism to improve the signal between the source and the destination. To support our claims, extensive simulations are performed.

  19. A Scalable Context-Aware Objective Function (SCAOF of Routing Protocol for Agricultural Low-Power and Lossy Networks (RPAL

    Directory of Open Access Journals (Sweden)

    Yibo Chen

    2015-08-01

    Full Text Available In recent years, IoT (Internet of Things technologies have seen great advances, particularly, the IPv6 Routing Protocol for Low-power and Lossy Networks (RPL, which provides a powerful and flexible routing framework that can be applied in a variety of application scenarios. In this context, as an important role of IoT, Wireless Sensor Networks (WSNs can utilize RPL to design efficient routing protocols for a specific application to increase the ubiquity of networks with resource-constrained WSN nodes that are low-cost and easy to deploy. In this article, our work starts with the description of Agricultural Low-power and Lossy Networks (A-LLNs complying with the LLN framework, and to clarify the requirements of this application-oriented routing solution. After a brief review of existing optimization techniques for RPL, our contribution is dedicated to a Scalable Context-Aware Objective Function (SCAOF that can adapt RPL to the environmental monitoring of A-LLNs, through combining energy-aware, reliability-aware, robustness-aware and resource-aware contexts according to the composite routing metrics approach. The correct behavior of this enhanced RPL version (RPAL was verified by performance evaluations on both simulation and field tests. The obtained experimental results confirm that SCAOF can deliver the desired advantages on network lifetime extension, and high reliability and efficiency in different simulation scenarios and hardware testbeds.

  20. A Scalable Context-Aware Objective Function (SCAOF) of Routing Protocol for Agricultural Low-Power and Lossy Networks (RPAL).

    Science.gov (United States)

    Chen, Yibo; Chanet, Jean-Pierre; Hou, Kun-Mean; Shi, Hongling; de Sousa, Gil

    2015-08-10

    In recent years, IoT (Internet of Things) technologies have seen great advances, particularly, the IPv6 Routing Protocol for Low-power and Lossy Networks (RPL), which provides a powerful and flexible routing framework that can be applied in a variety of application scenarios. In this context, as an important role of IoT, Wireless Sensor Networks (WSNs) can utilize RPL to design efficient routing protocols for a specific application to increase the ubiquity of networks with resource-constrained WSN nodes that are low-cost and easy to deploy. In this article, our work starts with the description of Agricultural Low-power and Lossy Networks (A-LLNs) complying with the LLN framework, and to clarify the requirements of this application-oriented routing solution. After a brief review of existing optimization techniques for RPL, our contribution is dedicated to a Scalable Context-Aware Objective Function (SCAOF) that can adapt RPL to the environmental monitoring of A-LLNs, through combining energy-aware, reliability-aware, robustness-aware and resource-aware contexts according to the composite routing metrics approach. The correct behavior of this enhanced RPL version (RPAL) was verified by performance evaluations on both simulation and field tests. The obtained experimental results confirm that SCAOF can deliver the desired advantages on network lifetime extension, and high reliability and efficiency in different simulation scenarios and hardware testbeds.

  1. Comparison of MANET routing protocols using a scaled indoor wireless grid

    CSIR Research Space (South Africa)

    Johnson, DL

    2008-04-01

    Full Text Available accumulation feature of Dynamic Source Routing (DSR) by adding the accumulated route, back to the source, to the Route Request packet. It retains the destination sequence number feature of AODV but HELLO packets are an optional feature and are normally left... than the inbound traffic as the routing algorithm makes a decision to rebroadcast the packet or not and Figure 20 confirms this. DYMO shows the least amount of routing traffic due to its lack of HELLO packets. This is also due to no further...

  2. AR-RBFS: Aware-Routing Protocol Based on Recursive Best-First Search Algorithm for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Farzad Kiani

    2016-01-01

    Full Text Available Energy issue is one of the most important problems in wireless sensor networks. They consist of low-power sensor nodes and a few base station nodes. They must be adaptive and efficient in data transmission to sink in various areas. This paper proposes an aware-routing protocol based on clustering and recursive search approaches. The paper focuses on the energy efficiency issue with various measures such as prolonging network lifetime along with reducing energy consumption in the sensor nodes and increasing the system reliability. Our proposed protocol consists of two phases. In the first phase (network development phase, the sensors are placed into virtual layers. The second phase (data transmission is related to routes discovery and data transferring so it is based on virtual-based Classic-RBFS algorithm in the lake of energy problem environments but, in the nonchargeable environments, all nodes in each layer can be modeled as a random graph and then begin to be managed by the duty cycle method. Additionally, the protocol uses new topology control, data aggregation, and sleep/wake-up schemas for energy saving in the network. The simulation results show that the proposed protocol is optimal in the network lifetime and packet delivery parameters according to the present protocols.

  3. Link reliability based hybrid routing for tactical mobile ad hoc network

    Institute of Scientific and Technical Information of China (English)

    Xie Xiaochuan; Wei Gang; Wu Keping; Wang Gang; Jia Shilou

    2008-01-01

    Tactical mobile ad hoc network (MANET) is a collection of mobile nodes forming a temporary network,without the aid of pre-established network infrastructure. The routing protocol has a crucial impact on the networkperformance in battlefields. Link reliability based hybrid routing (LRHR) is proposed, which is a novel hybrid routing protocol, for tactical MANET. Contrary to the traditional single path routing strategy, multiple paths are established between a pair of source-destination nodes. In the hybrid routing strategy, the rate of topological change provides a natural mechanism for switching dynamically between table-driven and on-demand routing. The simulation results indicate that the performances of the protocol in packet delivery ratio, routing overhead, and average end-to-end delay are better than the conventional routing protocol.

  4. On the Performance of the Current MANET Routing Protocols for VoIP, HTTP, and FTP Applications

    Directory of Open Access Journals (Sweden)

    Waheb A. Jabbar

    2014-01-01

    Full Text Available The recent advances of ensemble mobile environment of smart devices with embedded sensors have enabled the MANET to play a key role in the smart cities as well as WSN and WMN. However, these smart devices are still limited in terms of energy, processor, and memory. Moreover, the efficient routing for reliable network connectivity at anytime, anywhere, and about everything is still a challenge in multihop wireless networks. This paper evaluates the QoS and energy efficiency of three active routing protocols: (i OLSRv2, a successor to OLSR, (ii DYMO, a successor to both DSR and AODV, and (iii MP-OLSR multipath extension to OLSRv2. In contrast to the related previous works which focused only on CBR traffic without considering the influence of specific traffic types on the performance of routing protocols, this work focused on this area from a different perspective. It evaluates the performance of three internet-based traffic types that can be used in the smart city applications: VoIP, HTTP, and FTP using different simulation models. The impact of the network density, load traffic, and nodes mobility on the considered protocols was evaluated by considering particular performance metrics for each traffic application. Based on the results, the study concludes by presenting useful recommendations for future work.

  5. Simulation of Routing Protocol with CoS/QoS Enhancements in Heterogeneous Communication Network

    National Research Council Canada - National Science Library

    Kubera, Emil; Sliwa, Joanna; Zubel, Krzysztof; Mroczko, Adrian

    2006-01-01

    The article describes the subject of QoS routing mechanism in tactical heterogeneous communication network consisting of network elements built in different technologies and connected following rules...

  6. Overview of the Meraka wireless grid test bed for evaluation of ad-hoc routing protocols

    CSIR Research Space (South Africa)

    Johnson, D

    2007-09-01

    Full Text Available to the source, to the Route Request packet. It retains the destination sequence number feature of AODV but HELLO packets are an optional feature and are normally left out by default. It also does away with the gratuitous RREP feature of AODV. Routing... spiral algorithm makes a decision to rebroadcast the packet or not and Fig. 5. confirms this. DYMO shows the least amount of routing traffic due to its lack of HELLO packets. This is also due to no further routing packets being transmitted once...

  7. PROOF on Demand

    International Nuclear Information System (INIS)

    Malzacher, Peter; Manafov, Anar

    2010-01-01

    PROOF on Demand (PoD) is a set of utilities, which allows starting a PROOF cluster at user request, on any resource management system. It provides a plug-in based system, which allows to use different job submission frontends, such as LSF or gLite WMS. Main components of PoD are the PROOFAgent and the PAConsole. PROOFAgent provides the communication layer between the PROOF master on the local machine and the PROOF workers on the remote resources, possibly behind a firewall. PAConsole provides a user-friendly GUI, which is used to setup, manage, and shutdown the dynamic PROOF cluster. Installation is simple and doesn't require administrator privileges, and all the processes run in user space. PoD gives users, who don't have a centrally-administrated static PROOF cluster at their institute, the possibility to enjoy the full power of interactive analysis with PROOF.

  8. A Comparative Study of Novel Opportunistic Routing Protocols in Mobile Ad Hoc Networks

    OpenAIRE

    R. Poonkuzhali; M. Y. Sanavullah; M. R. Gurupriya

    2014-01-01

    Opportunistic routing is used, where the network has the features like dynamic topology changes and intermittent network connectivity. In Delay tolerant network or Disruption tolerant network opportunistic forwarding technique is widely used. The key idea of opportunistic routing is selecting forwarding nodes to forward data packets and coordination among these nodes to avoid duplicate transmissions. This paper gives the analysis of pros and cons of various opportunistic ...

  9. The Architecture of WiFi-Based WSN for AMR System and E-HWMP Routing Protocol

    Directory of Open Access Journals (Sweden)

    Li LI

    2014-02-01

    Full Text Available With the development of SoC technology in recent years, the ultra-low power WiFi System on SoC Chip has emerged. As a result, WiFi-based Wireless Sensor Networks come into use, especially used in Automatic Meter Reading. While because the nodes of Wireless Sensor Networks have limited energy supply, smaller storage capability and slower calculation ability, the current WiFi technology cannot be directly applied to WiFi-based Wireless Sensor Networks. The protocols should be upgraded and the security algorithms should be improved to meet the new requests. Firstly, this article describes the network architecture of WiFi-based WSN for AMR system and discusses the reason for using this analogous Mesh architecture. Secondly, the new Hardware architecture of WiFi-based WSN node is designed to realize the AMR system and verify the research work. The node can collect the data of power meter by WiFi and can be powered by a Lithium Battery. Thirdly, on the basis of study work of WiFi original routing protocol HWMP, a new method on improving the energy saving ability of HWMP to adapt the new features of WiFi-based WSN is proposed. And the simulation work on the new routing protocol E-HWMP has been done with NS2 and the simulation results show that the life cycle of the network has been extended to some degree.

  10. SIMULATION AND ANALYSIS OF GREEDY ROUTING PROTOCOL IN VIEW OF ENERGY CONSUMPTION AND NETWORK LIFETIME IN THREE DIMENSIONAL UNDERWATER WIRELESS SENSOR NETWORK

    Directory of Open Access Journals (Sweden)

    SHEENA KOHLI

    2017-11-01

    Full Text Available Underwater Wireless Sensor Network (UWSN comprises of a number of miniature sized sensing devices deployed in the sea or ocean, connected by dint of acoustic links to each other. The sensors trap the ambient conditions and transmit the data from one end to another. For transmission of data in any medium, routing protocols play a crucial role. Moreover, being battery limited, an unavoidable parameter to be considered in operation and analysis of protocols is the network energy and the network lifetime. The paper discusses the greedy routing protocol for underwater wireless sensor networks. The simulation of this routing protocol also takes into consideration the characteristics of acoustic communication like attenuation, transmission loss, signal to noise ratio, noise, propagation delay. The results from these observations may be used to construct an accurate underwater communication model.

  11. A Decentralized Fuzzy C-Means-Based Energy-Efficient Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Osama Moh’d Alia

    2014-01-01

    Full Text Available Energy conservation in wireless sensor networks (WSNs is a vital consideration when designing wireless networking protocols. In this paper, we propose a Decentralized Fuzzy Clustering Protocol, named DCFP, which minimizes total network energy dissipation to promote maximum network lifetime. The process of constructing the infrastructure for a given WSN is performed only once at the beginning of the protocol at a base station, which remains unchanged throughout the network’s lifetime. In this initial construction step, a fuzzy C-means algorithm is adopted to allocate sensor nodes into their most appropriate clusters. Subsequently, the protocol runs its rounds where each round is divided into a CH-Election phase and a Data Transmission phase. In the CH-Election phase, the election of new cluster heads is done locally in each cluster where a new multicriteria objective function is proposed to enhance the quality of elected cluster heads. In the Data Transmission phase, the sensing and data transmission from each sensor node to their respective cluster head is performed and cluster heads in turn aggregate and send the sensed data to the base station. Simulation results demonstrate that the proposed protocol improves network lifetime, data delivery, and energy consumption compared to other well-known energy-efficient protocols.

  12. A decentralized fuzzy C-means-based energy-efficient routing protocol for wireless sensor networks.

    Science.gov (United States)

    Alia, Osama Moh'd

    2014-01-01

    Energy conservation in wireless sensor networks (WSNs) is a vital consideration when designing wireless networking protocols. In this paper, we propose a Decentralized Fuzzy Clustering Protocol, named DCFP, which minimizes total network energy dissipation to promote maximum network lifetime. The process of constructing the infrastructure for a given WSN is performed only once at the beginning of the protocol at a base station, which remains unchanged throughout the network's lifetime. In this initial construction step, a fuzzy C-means algorithm is adopted to allocate sensor nodes into their most appropriate clusters. Subsequently, the protocol runs its rounds where each round is divided into a CH-Election phase and a Data Transmission phase. In the CH-Election phase, the election of new cluster heads is done locally in each cluster where a new multicriteria objective function is proposed to enhance the quality of elected cluster heads. In the Data Transmission phase, the sensing and data transmission from each sensor node to their respective cluster head is performed and cluster heads in turn aggregate and send the sensed data to the base station. Simulation results demonstrate that the proposed protocol improves network lifetime, data delivery, and energy consumption compared to other well-known energy-efficient protocols.

  13. A Decentralized Fuzzy C-Means-Based Energy-Efficient Routing Protocol for Wireless Sensor Networks

    Science.gov (United States)

    2014-01-01

    Energy conservation in wireless sensor networks (WSNs) is a vital consideration when designing wireless networking protocols. In this paper, we propose a Decentralized Fuzzy Clustering Protocol, named DCFP, which minimizes total network energy dissipation to promote maximum network lifetime. The process of constructing the infrastructure for a given WSN is performed only once at the beginning of the protocol at a base station, which remains unchanged throughout the network's lifetime. In this initial construction step, a fuzzy C-means algorithm is adopted to allocate sensor nodes into their most appropriate clusters. Subsequently, the protocol runs its rounds where each round is divided into a CH-Election phase and a Data Transmission phase. In the CH-Election phase, the election of new cluster heads is done locally in each cluster where a new multicriteria objective function is proposed to enhance the quality of elected cluster heads. In the Data Transmission phase, the sensing and data transmission from each sensor node to their respective cluster head is performed and cluster heads in turn aggregate and send the sensed data to the base station. Simulation results demonstrate that the proposed protocol improves network lifetime, data delivery, and energy consumption compared to other well-known energy-efficient protocols. PMID:25162060

  14. A Comparative Study of Wireless Sensor Networks and Their Routing Protocols

    OpenAIRE

    Subhajit Pal; Debnath Bhattacharyya; Tai-hoon Kim

    2010-01-01

    Recent developments in the area of micro-sensor devices have accelerated advances in the sensor networks field leading to many new protocols specifically designed for wireless sensor networks (WSNs). Wireless sensor networks with hundreds to thousands of sensor nodes can gather information from an unattended location and transmit the gathered data to a particular user, depending on the application. These sensor nodes have some constraints due to their limited energy, storage capacity and comp...

  15. Improved AODV route recovery in mobile ad-hoc networks using a genetic algorithm

    Directory of Open Access Journals (Sweden)

    Ahmad Maleki

    2014-09-01

    Full Text Available An important issue in ad-hoc on-demand distance vector (AODV routing protocols is route failure caused by node mobility in the MANETs. The AODV requires a new route discovery procedure whenever a route breaks and these frequent route discoveries increase transmission delays and routing overhead. The present study proposes a new method for AODVs using a genetic algorithm to improve the route recovery mechanism. When failure occurs in a route, the proposed method (GAAODV makes decisions regarding the QOS parameter to select source or local repair. The task of the genetic algorithm is to find an appropriate combination of weights to optimize end-to-end delay. This paper evaluates the metrics of routing overhead, average end-to-end delay, and packet delivery ratio. Comparison of the new algorithm and AODV (RFC 3561 using a NS-2 simulator shows that GAAODV obtains better results for the QOS parameters.

  16. Pharmacy on Demand Feasibility Assessment

    Science.gov (United States)

    2008-07-19

    quinolone structure. The synthesis is completed with a nucleophilic aromatic substitution with piperazine, followed by saponification and acidification...methyl ether in the presence of ester functionalities using boron tribromide at low temperature. The second route involves saponification of the...methyl ester, followed by esterification with tropine (Scheme 5B). Finally, the route described in Scheme 5C involves saponification , followed by

  17. DataBase on Demand

    International Nuclear Information System (INIS)

    Aparicio, R Gaspar; Gomez, D; Wojcik, D; Coz, I Coterillo

    2012-01-01

    At CERN a number of key database applications are running on user-managed MySQL database services. The database on demand project was born out of an idea to provide the CERN user community with an environment to develop and run database services outside of the actual centralised Oracle based database services. The Database on Demand (DBoD) empowers the user to perform certain actions that had been traditionally done by database administrators, DBA's, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently open community version of MySQL and single instance Oracle database server. This article describes a technology approach to face this challenge, a service level agreement, the SLA that the project provides, and an evolution of possible scenarios.

  18. Study of QoS control and reliable routing method for utility communication network. Application of differentiated service to the network and alternative route establishment by the IP routing protocol; Denryokuyo IP network no QoS seigyo to shinraisei kakuho no hoho. DiffServ ni yoru QoS seigyo no koka to IP ni yoru fuku root ka no kento

    Energy Technology Data Exchange (ETDEWEB)

    Oba, E.

    2000-05-01

    QoS control method which satisfies utilities communication network requirement and alternative route establishment method which is for sustaining communication during a failure are studied. Applicability of DiffServ (Differentiated Service), one of the most promising QoS control method on IP network and studying energetically in IETF WG, is studied and it is found most application used in the utility communication network except for relaying system information could he accommodated to the DiffServ network. An example of the napping of the utility communication applications to the DiffServ PHB (Per Hop Behavior) is shown in this paper. Regarding to the alternative route, usual IP routing protocol cannot establish alternative route which doesn't have common links and nodes in their paths for a destination. IP address duplication with some modification of routing protocol enables such alternative route establishment. MPLS, distance vector algorithm and link state algorithm are evaluated qualitatively, and as a result, we found MPLS is promising way to establish the route. Quantitative evaluation will be future work. (author)

  19. Verifikasi Dua Varian Protokol Ad hoc On demand Distance Vector dengan UPPAAL

    Directory of Open Access Journals (Sweden)

    Ika Oktavia Suzanti

    2015-01-01

    Abstract  MANET is a group of wireless mobile that connected one to each other without fixed infrastructure so topology could change at anytime. MANET routing protocol has two models which are reactive routing protocol that built routing table only when needed and proactive routing protocol that maintain routing table periodically. General property which had to be satisfied by ad-hoc network protocol are route discovery, packet delivery and loop freedom. AODV is a reactive protocol in MANET that has time standard to determine how long a route is valid to be used (route validity so route discovery and packet delivery property should be satisfied in a specifically certain time. Protocol verification process done by modeling protocol specification using technique, tool and mathematic language. In this research protocol modeled using timed automata which is a modeling language that could be used to model a time dependent system in each process. Verification using timed automata can automatically done by UPPAAL tool model checker. Protocol which will be verified are AODV Break Avoidance by Ali Khosrozadeh et al. and AODV Reliable Delivery by Liu Jian and Fang-Min. Result of this protocol verification prove that AODV BA could satisfied route discovery property and AODV Reliable Delivery could satisfied packet delivery property within their specification time.   Keywords—Protocol Verification, Timed Automata, AODV, UPPAAL

  20. Cooperative Optimization QoS Cloud Routing Protocol Based on Bacterial Opportunistic Foraging and Chemotaxis Perception for Mobile Internet

    Directory of Open Access Journals (Sweden)

    Shujuan Wang

    2015-01-01

    Full Text Available In order to strengthen the mobile Internet mobility management and cloud platform resources utilization, optimizing the cloud routing efficiency is established, based on opportunistic bacterial foraging bionics, and puts forward a chemotaxis perception of collaborative optimization QoS (Quality of Services cloud routing mechanism. The cloud routing mechanism is based on bacterial opportunity to feed and bacterial motility and to establish the data transmission and forwarding of the bacterial population behavior characteristics. This mechanism is based on the characteristics of drug resistance of bacteria and the structure of the field, and through many iterations of the individual behavior and population behavior the bacteria can be spread to the food gathering area with a certain probability. Finally, QoS cloud routing path would be selected and optimized based on bacterial bionic optimization and hedge mapping relationship between mobile Internet node and bacterial population evolution iterations. Experimental results show that, compared with the standard dynamic routing schemes, the proposed scheme has shorter transmission delay, lower packet error ratio, QoS cloud routing loading, and QoS cloud route request overhead.

  1. A Link Quality and Geographical-aware Routing Protocol for Video Transmission in Mobile IoT

    OpenAIRE

    Rosário, Denis; Zhao, Zhongliang; Cerqueira, Eduardo; Braun, Torsten; Santos, Aldri

    2013-01-01

    Wireless mobile sensor networks are enlarging the Internet of Things (IoT) portfolio with a huge number of multimedia services for smart cities. Safety and environmental monitoring multimedia applications will be part of the Smart IoT systems, which aim to reduce emergency response time, while also predicting hazardous events. In these mobile and dynamic (possible disaster) scenarios, opportunistic routing allows routing decisions in a completely distributed manner, by using a hop- by-hop rou...

  2. Effective ANT based Routing Algorithm for Data Replication in MANETs

    Directory of Open Access Journals (Sweden)

    N.J. Nithya Nandhini

    2013-12-01

    Full Text Available In mobile ad hoc network, the nodes often move and keep on change its topology. Data packets can be forwarded from one node to another on demand. To increase the data accessibility data are replicated at nodes and made as sharable to other nodes. Assuming that all mobile host cooperative to share their memory and allow forwarding the data packets. But in reality, all nodes do not share the resources for the benefits of others. These nodes may act selfishly to share memory and to forward the data packets. This paper focuses on selfishness of mobile nodes in replica allocation and routing protocol based on Ant colony algorithm to improve the efficiency. The Ant colony algorithm is used to reduce the overhead in the mobile network, so that it is more efficient to access the data than with other routing protocols. This result shows the efficiency of ant based routing algorithm in the replication allocation.

  3. The Integron: Adaptation On Demand.

    Science.gov (United States)

    Escudero, José Antonio; Loot, Céline; Nivina, Aleksandra; Mazel, Didier

    2015-04-01

    The integron is a powerful system which, by capturing, stockpiling, and rearranging new functions carried by gene encoding cassettes, confers upon bacteria a rapid adaptation capability in changing environments. Chromosomally located integrons (CI) have been identified in a large number of environmental Gram-negative bacteria. Integron evolutionary history suggests that these sedentary CIs acquired mobility among bacterial species through their association with transposable elements and conjugative plasmids. As a result of massive antibiotic use, these so-called mobile integrons are now widespread in clinically relevant bacteria and are considered to be the principal agent in the emergence and rise of antibiotic multiresistance in Gram-negative bacteria. Cassette rearrangements are catalyzed by the integron integrase, a site-specific tyrosine recombinase. Central to these reactions is the single-stranded DNA nature of one of the recombination partners, the attC site. This makes the integron a unique recombination system. This review describes the current knowledge on this atypical recombination mechanism, its implications in the reactions involving the different types of sites, attC and attI, and focuses on the tight regulation exerted by the host on integron activity through the control of attC site folding. Furthermore, cassette and integrase expression are also highly controlled by host regulatory networks and the bacterial stress (SOS) response. These intimate connections to the host make the integron a genetically stable and efficient system, granting the bacteria a low cost, highly adaptive evolution potential "on demand".

  4. BATMAN: MOS Spectroscopy on Demand

    Science.gov (United States)

    Molinari, E.; Zamkotsian, F.; Moschetti, M.; Spano, P.; Boschin, W.; Cosentino, R.; Ghedina, A.; González, M.; Pérez, H.; Lanzoni, P.; Ramarijaona, H.; Riva, M.; Zerbi, F.; Nicastro, L.; Valenziano, L.; Di Marcantonio, P.; Coretti, I.; Cirami, R.

    2016-10-01

    Multi-Object Spectrographs (MOS) are the major instruments for studying primary galaxies and remote and faint objects. Current object selection systems are limited and/or difficult to implement in next generation MOS for space and ground-based telescopes. A promising solution is the use of MOEMS devices such as micromirror arrays, which allow the remote control of the multi-slit configuration in real time. TNG is hosting a novelty project for real-time, on-demand MOS masks based on MOEMS programmable slits. We are developing a 2048×1080 Digital-Micromirror-Device-based (DMD) MOS instrument to be mounted on the Galileo telescope, called BATMAN. It is a two-arm instrument designed for providing in parallel imaging and spectroscopic capabilities. With a field of view of 6.8×3.6 arcmin and a plate scale of 0.2 arcsec per micromirror, this astronomical setup can be used to investigate the formation and evolution of galaxies. The wavelength range is in the visible and the spectral resolution is R=560 for a 1 arcsec object, and the two arms will have 2k × 4k CCD detectors. ROBIN, a BATMAN demonstrator, has been designed, realized and integrated. We plan to have BATMAN first light by mid-2016.

  5. A Multi-User Game-Theoretical Multipath Routing Protocol to Send Video-Warning Messages over Mobile Ad Hoc Networks.

    Science.gov (United States)

    Mezher, Ahmad Mohamad; Igartua, Mónica Aguilar; de la Cruz Llopis, Luis J; Pallarès Segarra, Esteve; Tripp-Barba, Carolina; Urquiza-Aguiar, Luis; Forné, Jordi; Sanvicente Gargallo, Emilio

    2015-04-17

    The prevention of accidents is one of the most important goals of ad hoc networks in smart cities. When an accident happens, dynamic sensors (e.g., citizens with smart phones or tablets, smart vehicles and buses, etc.) could shoot a video clip of the accident and send it through the ad hoc network. With a video message, the level of seriousness of the accident could be much better evaluated by the authorities (e.g., health care units, police and ambulance drivers) rather than with just a simple text message. Besides, other citizens would be rapidly aware of the incident. In this way, smart dynamic sensors could participate in reporting a situation in the city using the ad hoc network so it would be possible to have a quick reaction warning citizens and emergency units. The deployment of an efficient routing protocol to manage video-warning messages in mobile Ad hoc Networks (MANETs) has important benefits by allowing a fast warning of the incident, which potentially can save lives. To contribute with this goal, we propose a multipath routing protocol to provide video-warning messages in MANETs using a novel game-theoretical approach. As a base for our work, we start from our previous work, where a 2-players game-theoretical routing protocol was proposed to provide video-streaming services over MANETs. In this article, we further generalize the analysis made for a general number of N players in the MANET. Simulations have been carried out to show the benefits of our proposal, taking into account the mobility of the nodes and the presence of interfering traffic. Finally, we also have tested our approach in a vehicular ad hoc network as an incipient start point to develop a novel proposal specifically designed for VANETs.

  6. A Multi-User Game-Theoretical Multipath Routing Protocol to Send Video-Warning Messages over Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Ahmad Mohamad Mezher

    2015-04-01

    Full Text Available The prevention of accidents is one of the most important goals of ad hoc networks in smart cities. When an accident happens, dynamic sensors (e.g., citizens with smart phones or tablets, smart vehicles and buses, etc. could shoot a video clip of the accident and send it through the ad hoc network. With a video message, the level of seriousness of the accident could be much better evaluated by the authorities (e.g., health care units, police and ambulance drivers rather than with just a simple text message. Besides, other citizens would be rapidly aware of the incident. In this way, smart dynamic sensors could participate in reporting a situation in the city using the ad hoc network so it would be possible to have a quick reaction warning citizens and emergency units. The deployment of an efficient routing protocol to manage video-warning messages in mobile Ad hoc Networks (MANETs has important benefits by allowing a fast warning of the incident, which potentially can save lives. To contribute with this goal, we propose a multipath routing protocol to provide video-warning messages in MANETs using a novel game-theoretical approach. As a base for our work, we start from our previous work, where a 2-players game-theoretical routing protocol was proposed to provide video-streaming services over MANETs. In this article, we further generalize the analysis made for a general number of N players in the MANET. Simulations have been carried out to show the benefits of our proposal, taking into account the mobility of the nodes and the presence of interfering traffic. Finally, we also have tested our approach in a vehicular ad hoc network as an incipient start point to develop a novel proposal specifically designed for VANETs.

  7. On Designing Thermal-Aware Localized QoS Routing Protocol for in-vivo Sensor Nodes in Wireless Body Area Networks

    OpenAIRE

    Monowar, Muhammad Mostafa; Bajaber, Fuad

    2015-01-01

    In this paper, we address the thermal rise and Quality-of-Service (QoS) provisioning issue for an intra-body Wireless Body Area Network (WBAN) having in-vivo sensor nodes. We propose a thermal-aware QoS routing protocol, called TLQoS, that facilitates the system in achieving desired QoS in terms of delay and reliability for diverse traffic types, as well as avoids the formation of highly heated nodes known as hotspot(s), and keeps the temperature rise along the network to an acceptable level....

  8. A model to improve the routing performance of Cognitive Radio Wireless Mesh Networks

    Directory of Open Access Journals (Sweden)

    Lesiba Morries Kola

    2017-12-01

    Full Text Available The increasing demand for broadband wireless technologies has led to the scarcity, inefficient utilization, and underutilization of the spectrum. The Cognitive Radio (CR technology has emerged as the promising solution which improves the utilization of the spectrum. However, routing is a challenge due to the dynamic nature of the CR networks. The link quality varies in space and time as nodes join and leave the network. The network connectivity is intermittent due to node mobility and the activities of the primary user. The spectrum aware, spectrum agile, and interference aware routing protocols are vital for the sturdiness of the network and efficient utilization of the resources. We propose an interference aware, spectrum aware, and agile extended Weighted Cumulative Expected Transmission Time (xWCETT routing protocol. The protocol integrates the features of the Ad-hoc On-demand Distance Vector (AODV and the weighted cumulative expected transmission time (WCETT routing protocols. The xWCETT was simulated using the Network Simulator 2 and its performance compared with the AODV and the WCETT routing protocols. The xWCETT was evaluated with respect to quality of service related metrics and the results show that it outperformed the AODV and WCETT routing protocols.

  9. Selective Route Based on SNR with Cross-Layer Scheme in Wireless Ad Hoc Network

    Directory of Open Access Journals (Sweden)

    Istikmal

    2017-01-01

    Full Text Available In this study, we developed network and throughput formulation models and proposed new method of the routing protocol algorithm with a cross-layer scheme based on signal-to-noise ratio (SNR. This method is an enhancement of routing protocol ad hoc on-demand distance vector (AODV. This proposed scheme uses selective route based on the SNR threshold in the reverse route mechanism. We developed AODV SNR-selective route (AODV SNR-SR for a mechanism better than AODV SNR, that is, the routing protocol that used average or sum of path SNR, and also better than AODV which is hop-count-based. We also used selective reverse route based on SNR mechanism, replacing the earlier method to avoid routing overhead. The simulation results show that AODV SNR-SR outperforms AODV SNR and AODV in terms of throughput, end-to-end delay, and routing overhead. This proposed method is expected to support Device-to-Device (D2D communications that are concerned with the quality of the channel awareness in the development of the future Fifth Generation (5G.

  10. Location-Aided Reliable Routing for Opportunistic Networks

    Institute of Scientific and Technical Information of China (English)

    Yong Yang; Zhi Ren; Jibi Li

    2012-01-01

    In our study, we investigate the problem of location-based routing in opportunistic networks. Due to the uncertainty of end-to-end paths between sources and destinations, the classical location-based ad hoc routing protocols cannot adapt to the environment of opportunistic networks, which leads to the decrease of the delivery rate of data. To address it, we propose in this paper a novel location-aided routing protocol which is suitable for opportunistic networks. In our protocol, a node can send location information on demand by using prediction mechanism, and when sending a data packet, the node chooses multiple neighbors which are closer to the destination as next hops. If the candidate neighbors do not exist, the node carries the data till it meets a proper neighbor or the destination. Theoretical analysis and simulation results show that our proposed protocol outperforms DREAM (Distance Routing Effect Protocol Mobility) and one of its improved versions, BFDREAM (Boundary Forwarding DREAM), in terms of the delivery rate and overhead.

  11. Power Balance AODV Routing Algorithm of WSN in Precision Agriculture Environment Monitoring

    Directory of Open Access Journals (Sweden)

    Xiaoqin Qin

    2013-11-01

    Full Text Available As one of important technologies of IOT (Internet of Things, WSN (Wireless Sensor Networks has been widely used in precision agriculture environment monitoring. WSN is a kind of energy-constrained network, but power balance is not taken into account in traditional routing protocols. A novel routing algorithm, named Power Balance Ad hoc On-Demand Distance Vector (PB-AODV, is proposed on cross-layer design. In the route discovery process of PB-AODV, routing path is established by the Received Signal Strength Indication (RSSI value. The optimal transmitting power, which is computed according to RSSI value, power threshold and node’s surplus energy, is encapsulated into Route Reply Packet. Hence, the sender node can adjust its transmission power to save energy according to the Route Reply Packet. Simulation results show that the proposed algorithm is effective for load balancing, and increases the WSN’s lifetime 14.3% consequently.

  12. On Designing Thermal-Aware Localized QoS Routing Protocol for in-vivo Sensor Nodes in Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Mostafa Monowar

    2015-06-01

    Full Text Available In this paper, we address the thermal rise and Quality-of-Service (QoS provisioning issue for an intra-body Wireless Body Area Network (WBAN having in-vivo sensor nodes. We propose a thermal-aware QoS routing protocol, called TLQoS, that facilitates the system in achieving desired QoS in terms of delay and reliability for diverse traffic types, as well as avoids the formation of highly heated nodes known as hotspot(s, and keeps the temperature rise along the network to an acceptable level. TLQoS exploits modular architecture wherein different modules perform integrated operations in providing multiple QoS service with lower temperature rise. To address the challenges of highly dynamic wireless environment inside the human body. TLQoS implements potential-based localized routing that requires only local neighborhood information. TLQoS avoids routing loop formation as well as reduces the number of hop traversal exploiting hybrid potential, and tuning a configurable parameter. We perform extensive simulations of TLQoS, and the results show that TLQoS has significant performance improvements over state-of-the-art approaches.

  13. On Designing Thermal-Aware Localized QoS Routing Protocol for in-vivo Sensor Nodes in Wireless Body Area Networks.

    Science.gov (United States)

    Monowar, Muhammad Mostafa; Bajaber, Fuad

    2015-06-15

    In this paper, we address the thermal rise and Quality-of-Service (QoS) provisioning issue for an intra-body Wireless Body Area Network (WBAN) having in-vivo sensor nodes. We propose a thermal-aware QoS routing protocol, called TLQoS, that facilitates the system in achieving desired QoS in terms of delay and reliability for diverse traffic types, as well as avoids the formation of highly heated nodes known as hotspot(s), and keeps the temperature rise along the network to an acceptable level. TLQoS exploits modular architecture wherein different modules perform integrated operations in providing multiple QoS service with lower temperature rise. To address the challenges of highly dynamic wireless environment inside the human body. TLQoS implements potential-based localized routing that requires only local neighborhood information. TLQoS avoids routing loop formation as well as reduces the number of hop traversal exploiting hybrid potential, and tuning a configurable parameter. We perform extensive simulations of TLQoS, and the results show that TLQoS has significant performance improvements over state-of-the-art approaches.

  14. OPTIMASI OLSR ROUTING PROTOCOL PADA JARINGAN WIRELESS MESH DENGAN ADAPTIVE REFRESHING TIME INTERVAL DAN ENHANCE MULTI POINT RELAY SELECTING ALGORITHM

    Directory of Open Access Journals (Sweden)

    Faosan Mapa

    2014-01-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Wireless Mesh Network (WMN adalah suatu konektivitas jaringan yang self-organized, self-configured dan multi-hop. Tujuan dari WMN adalah menawarkan pengguna suatu bentuk jaringan nirkabel yang dapat dengan mudah berkomunikasi dengan jaringan konvensional dengan kecepatan tinggi dan dengan cakupan yang lebih luas serta biaya awal yang minimal. Diperlukan suatu desain protokol routing yang efisien untuk WMN yang secara adaptif dapat mendukung mesh routers dan mesh clients. Dalam tulisan ini, diusulkan untuk mengoptimalkan protokol OLSR, yang merupakan protokol routing proaktif. Digunakan heuristik yang meningkatkan protokol OLSR melalui adaptive refreshing time interval dan memperbaiki metode MPR selecting algorithm. Suatu analisa dalam meningkatkan protokol OLSR melalui adaptive refreshing time interval dan memperbaiki algoritma pemilihan MPR menunjukkan kinerja yang signifikan dalam hal throughput jika dibandingkan dengan protokol OLSR yang asli. Akan tetapi, terdapat kenaikan dalam hal delay. Pada simulasi yang dilakukan dapat disimpulkan bahwa OLSR dapat dioptimalkan dengan memodifikasi pemilihan node MPR berdasarkan cost effective dan penyesuaian waktu interval refreshing hello message sesuai dengan keadaan

  15. An Adaptive QoS Routing Solution for MANET Based Multimedia Communications in Emergency Cases

    Science.gov (United States)

    Ramrekha, Tipu Arvind; Politis, Christos

    The Mobile Ad hoc Networks (MANET) is a wireless network deprived of any fixed central authoritative routing entity. It relies entirely on collaborating nodes forwarding packets from source to destination. This paper describes the design, implementation and performance evaluation of CHAMELEON, an adaptive Quality of Service (QoS) routing solution, with improved delay and jitter performances, enabling multimedia communication for MANETs in extreme emergency situations such as forest fire and terrorist attacks as defined in the PEACE project. CHAMELEON is designed to adapt its routing behaviour according to the size of a MANET. The reactive Ad Hoc on-Demand Distance Vector Routing (AODV) and proactive Optimized Link State Routing (OLSR) protocols are deemed appropriate for CHAMELEON through their performance evaluation in terms of delay and jitter for different MANET sizes in a building fire emergency scenario. CHAMELEON is then implemented in NS-2 and evaluated similarly. The paper concludes with a summary of findings so far and intended future work.

  16. High throughput route selection in multi-rate wireless mesh networks

    Institute of Scientific and Technical Information of China (English)

    WEI Yi-fei; GUO Xiang-li; SONG Mei; SONG Jun-de

    2008-01-01

    Most existing Ad-hoc routing protocols use the shortest path algorithm with a hop count metric to select paths. It is appropriate in single-rate wireless networks, but has a tendency to select paths containing long-distance links that have low data rates and reduced reliability in multi-rate networks. This article introduces a high throughput routing algorithm utilizing the multi-rate capability and some mesh characteristics in wireless fidelity (WiFi) mesh networks. It uses the medium access control (MAC) transmission time as the routing metric, which is estimated by the information passed up from the physical layer. When the proposed algorithm is adopted, the Ad-hoc on-demand distance vector (AODV) routing can be improved as high throughput AODV (HT-AODV). Simulation results show that HT-AODV is capable of establishing a route that has high data-rate, short end-to-end delay and great network throughput.

  17. Predicting Catastrophic BGP Routing Instabilities

    National Research Council Canada - National Science Library

    Nguyen, Lien

    2004-01-01

    .... Currently, this critical function is performed by the Border Gateway Protocol (BGP) version 4 RF01771. Like all routing protocols, BGP is vulnerable to instabilities that reduce its effectiveness...

  18. Multihop Wireless Networks Opportunistic Routing

    CERN Document Server

    Zeng, Kai; Li, Ming

    2011-01-01

    This book provides an introduction to opportunistic routing an emerging technology designed to improve the packet forwarding reliability, network capacity and energy efficiency of multihop wireless networks This book presents a comprehensive background to the technological challenges lying behind opportunistic routing. The authors cover many fundamental research issues for this new concept, including the basic principles, performance limit and performance improvement of opportunistic routing compared to traditional routing, energy efficiency and distributed opportunistic routing protocol desig

  19. Mobility on Demand Operational Concept Report.

    Science.gov (United States)

    2017-09-10

    This operational concept report provides an overview of the Mobility on Demand (MOD) concept and its evolution, description of the MOD ecosystem in a supply and demand framework, and its stakeholders and enablers. Leveraging the MOD ecosystem framewo...

  20. Beyond Traditional DTN Routing: Social Networks for Opportunistic Communication

    OpenAIRE

    Schurgot, Mary R.; Comaniciu, Cristina; Jaffrès-Runser, Katia

    2011-01-01

    This article examines the evolution of routing protocols for intermittently connected ad hoc networks and discusses the trend toward social-based routing protocols. A survey of current routing solutions is presented, where routing protocols for opportunistic networks are classified based on the network graph employed. The need to capture performance tradeoffs from a multi-objective perspective is highlighted.

  1. On-demand microbicide products: design matters.

    Science.gov (United States)

    Patel, Sravan Kumar; Rohan, Lisa Cencia

    2017-12-01

    Sexual intercourse (vaginal and anal) is the predominant mode of human immunodeficiency virus (HIV) transmission. Topical microbicides used in an on-demand format (i.e., immediately before or after sex) can be part of an effective tool kit utilized to prevent sexual transmission of HIV. The effectiveness of prevention products is positively correlated with adherence, which is likely to depend on user acceptability of the product. The development of an efficacious and acceptable product is therefore paramount for the success of an on-demand product. Acceptability of on-demand products (e.g., gels, films, and tablets) and their attributes is influenced by a multitude of user-specific factors that span behavioral, lifestyle, socio-economic, and cultural aspects. In addition, physicochemical properties of the drug, anatomical and physiological aspects of anorectal and vaginal compartments, issues relating to large-scale production, and cost can impact product development. These factors together with user preferences determine the design space of an effective, acceptable, and feasible on-demand product. In this review, we summarize the interacting factors that together determine product choice and its target product profile.

  2. Aviation Frontiers: On-Demand Aircraft

    Science.gov (United States)

    Moore, Mark D.

    2010-01-01

    Throughout the 20th Century, NASA has defined the forefront of aeronautical technology, and the aviation industry owes much of its prosperity to this knowledge and technology. In recent decades, centralized aeronautics has become a mature discipline, which raises questions concerning the future aviation innovation frontiers. Three transformational aviation capabilities, bounded together by the development of a Free Flight airspace management system, have the potential to transform 21st Century society as profoundly as civil aviation transformed the 20th Century. These mobility breakthroughs will re-establish environmental sustainable centralized aviation, while opening up latent markets for civil distributed sensing and on-demand rural and regional transportation. Of these three transformations, on-demand aviation has the potential to have the largest market and productivity improvement to society. The information system revolution over the past 20 years shows that vehicles lead, and the interconnecting infrastructure to make them more effective follows; that is, unless on-demand aircraft are pioneered, a distributed Air Traffic Control system will likely never be established. There is no single technology long-pole that will enable on-demand vehicle solutions. However, fully digital aircraft that include electric propulsion has the potential to be a multi-disciplinary initiator of solid state technologies that can provide order of magnitude improvements in the ease of use, safety/reliability, community and environmental friendliness, and affordability.

  3. Bandwidth-on-demand motion control

    NARCIS (Netherlands)

    Van Loon, S.J.L.M.; Hunnekens, B.G.B.; Simon, A.S.; van de Wouw, N.; Heemels, W.P.M.H.

    2018-01-01

    In this brief, we introduce a 'bandwidth-on-demand' variable-gain control (VGC) strategy that allows for a varying bandwidth of the feedback controller. The proposed VGC can achieve improved performance given time-varying, reference-dependent performance requirements compared with linear

  4. Fabricate-On-Demand Vacuum Insulating Glazings

    Energy Technology Data Exchange (ETDEWEB)

    McCamy, James W. [PPG Industries, Inc., Pittsburgh, PA (United States)

    2017-09-19

    PPG proposed to design a fabricate-on-demand manufacturing process to overcome the cost and supply chain issues preventing widespread adoption of vacuum insulated glazing (VIG) units. To do so, we focused on improving three areas of VIG manufacturing that drive high costs and limit the ability for smaller manufacturers to enter the market: edge sealing, pillar design/placement, and evacuating the VIG.

  5. Unmanned Aerial ad Hoc Networks: Simulation-Based Evaluation of Entity Mobility Models’ Impact on Routing Performance

    Directory of Open Access Journals (Sweden)

    Jean-Daniel Medjo Me Biomo

    2015-06-01

    Full Text Available An unmanned aerial ad hoc network (UAANET is a special type of mobile ad hoc network (MANET. For these networks, researchers rely mostly on simulations to evaluate their proposed networking protocols. Hence, it is of great importance that the simulation environment of a UAANET replicates as much as possible the reality of UAVs. One major component of that environment is the movement pattern of the UAVs. This means that the mobility model used in simulations has to be thoroughly understood in terms of its impact on the performance of the network. In this paper, we investigate how mobility models affect the performance of UAANET in simulations in order to come up with conclusions/recommendations that provide a benchmark for future UAANET simulations. To that end, we first propose a few metrics to evaluate the mobility models. Then, we present five random entity mobility models that allow nodes to move almost freely and independently from one another and evaluate four carefully-chosen MANET/UAANET routing protocols: ad hoc on-demand distance vector (AODV, optimized link state routing (OLSR, reactive-geographic hybrid routing (RGR and geographic routing protocol (GRP. In addition, flooding is also evaluated. The results show a wide variation of the protocol performance over different mobility models. These performance differences can be explained by the mobility model characteristics, and we discuss these effects. The results of our analysis show that: (i the enhanced Gauss–Markov (EGM mobility model is best suited for UAANET; (ii OLSR, a table-driven proactive routing protocol, and GRP, a position-based geographic protocol, are the protocols most sensitive to the change of mobility models; (iii RGR, a reactive-geographic hybrid routing protocol, is best suited for UAANET.

  6. New Product Development Based on Demand

    OpenAIRE

    Davis-Krook, Shelby

    2015-01-01

    The purpose of this thesis was to determine how to develop a new product based on demand within a target market for an international company. Specifically looking at developing a new product line in an already developed brand, Alpha Performance. The research I have conducted in the following topics may help Alpha Performance if they choose to use my findings to create a one of a kind woman’s clothing line based on the demands of the Finnish market: target market research, product demand rese...

  7. Achieving a Launch on Demand Capability

    Science.gov (United States)

    Greenberg, Joel S.

    2002-01-01

    The ability to place payloads [satellites] into orbit as and when required, often referred to as launch on demand, continues to be an elusive and yet largely unfulfilled goal. But what is the value of achieving launch on demand [LOD], and what metrics are appropriate? Achievement of a desired level of LOD capability must consider transportation system thruput, alternative transportation systems that comprise the transportation architecture, transportation demand, reliability and failure recovery characteristics of the alternatives, schedule guarantees, launch delays, payload integration schedules, procurement policies, and other factors. Measures of LOD capability should relate to the objective of the transportation architecture: the placement of payloads into orbit as and when required. Launch on demand capability must be defined in probabilistic terms such as the probability of not incurring a delay in excess of T when it is determined that it is necessary to place a payload into orbit. Three specific aspects of launch on demand are considered: [1] the ability to recover from adversity [i.e., a launch failure] and to keep up with the steady-state demand for placing satellites into orbit [this has been referred to as operability and resiliency], [2] the ability to respond to the requirement to launch a satellite when the need arises unexpectedly either because of an unexpected [random] on-orbit satellite failure that requires replacement or because of the sudden recognition of an unanticipated requirement, and [3] the ability to recover from adversity [i.e., a launch failure] during the placement of a constellation into orbit. The objective of this paper is to outline a formal approach for analyzing alternative transportation architectures in terms of their ability to provide a LOD capability. The economic aspect of LOD is developed by establishing a relationship between scheduling and the elimination of on-orbit spares while achieving the desired level of on

  8. Congestion control and routing over satellite networks

    Science.gov (United States)

    Cao, Jinhua

    ) method and then develop a novel on-demand routing system named Cross Entropy Accelerated Ant Routing System (CEAARS) for regular constellation LEO satellite networks. By implementing simulations on an Iridium-like satellite network, we compare the proposed CEAARS algorithm with the two approaches to adaptive routing protocols on the Internet: distance-vector (DV) and link-state (LS), as well as with the original Cross Entropy Ant Routing System (CEARS). DV algorithms are based on distributed Bellman Ford algorithm, and LS algorithms are implementation of Dijkstras single source shortest path. The results show that CEAARS not only remarkably improves the convergence speed of achieving optimal or suboptimal paths, but also reduces the number of overhead ants (management packets).

  9. Experimental demonstration of bandwidth on demand (BoD) provisioning based on time scheduling in software-defined multi-domain optical networks

    Science.gov (United States)

    Zhao, Yongli; Li, Yajie; Wang, Xinbo; Chen, Bowen; Zhang, Jie

    2016-09-01

    A hierarchical software-defined networking (SDN) control architecture is designed for multi-domain optical networks with the Open Daylight (ODL) controller. The OpenFlow-based Control Virtual Network Interface (CVNI) protocol is deployed between the network orchestrator and the domain controllers. Then, a dynamic bandwidth on demand (BoD) provisioning solution is proposed based on time scheduling in software-defined multi-domain optical networks (SD-MDON). Shared Risk Link Groups (SRLG)-disjoint routing schemes are adopted to separate each tenant for reliability. The SD-MDON testbed is built based on the proposed hierarchical control architecture. Then the proposed time scheduling-based BoD (Ts-BoD) solution is experimentally demonstrated on the testbed. The performance of the Ts-BoD solution is evaluated with respect to blocking probability, resource utilization, and lightpath setup latency.

  10. Building a print on demand web service

    Science.gov (United States)

    Reddy, Prakash; Rozario, Benedict; Dudekula, Shariff; V, Anil Dev

    2011-03-01

    There is considerable effort underway to digitize all books that have ever been printed. There is need for a service that can take raw book scans and convert them into Print on Demand (POD) books. Such a service definitely augments the digitization effort and enables broader access to a wider audience. To make this service practical we have identified three key challenges that needed to be addressed. These are: a) produce high quality image images by eliminating artifacts that exist due to the age of the document or those that are introduced during the scanning process b) develop an efficient automated system to process book scans with minimum human intervention; and c) build an eco system which allows us the target audience to discover these books.

  11. A new method for improving security in MANETs AODV Protocol

    Directory of Open Access Journals (Sweden)

    Zahra Alishahi

    2012-10-01

    Full Text Available In mobile ad hoc network (MANET, secure communication is more challenging task due to its fundamental characteristics like having less infrastructure, wireless link, distributed cooperation, dynamic topology, lack of association, resource constrained and physical vulnerability of node. In MANET, attacks can be broadly classified in two categories: routing attacks and data forwarding attacks. Any action not following rules of routing protocols belongs to routing attacks. The main objective of routing attacks is to disrupt normal functioning of network by advertising false routing updates. On the other hand, data forwarding attacks include actions such as modification or dropping data packet, which does not disrupt routing protocol. In this paper, we address the “Packet Drop Attack”, which is a serious threat to operational mobile ad hoc networks. The consequence of not forwarding other packets or dropping other packets prevents any kind of communication to be established in the network. Therefore, there is a need to address the packet dropping event takes higher priority for the mobile ad hoc networks to emerge and to operate, successfully. In this paper, we propose a method to secure ad hoc on-demand distance vector (AODV routing protocol. The proposed method provides security for routing packets where the malicious node acts as a black-hole and drops packets. In this method, the collaboration of a group of nodes is used to make accurate decisions. Validating received RREPs allows the source to select trusted path to its destination. The simulation results show that the proposed mechanism is able to detect any number of attackers.

  12. Service on demand for ISS users

    Science.gov (United States)

    Hüser, Detlev; Berg, Marco; Körtge, Nicole; Mildner, Wolfgang; Salmen, Frank; Strauch, Karsten

    2002-07-01

    Since the ISS started its operational phase, the need of logistics scenarios and solutions, supporting the utilisation of the station and its facilities, becomes increasingly important. Our contribution to this challenge is a SERVICE On DEMAND for ISS users, which offers a business friendly engineering and logistics support for the resupply of the station. Especially the utilisation by commercial and industrial users is supported and simplified by this service. Our industrial team, consisting of OHB-System and BEOS, provides experience and development support for space dedicated hard- and software elements, their transportation and operation. Furthermore, we operate as the interface between customer and the envisaged space authorities. Due to a variety of tailored service elements and the ongoing servicing, customers can concentrate on their payload content or mission objectives and don't have to deal with space-specific techniques and regulations. The SERVICE On DEMAND includes the following elements: ITR is our in-orbit platform service. ITR is a transport rack, used in the SPACEHAB logistics double module, for active and passive payloads on subrack- and drawer level of different standards. Due to its unique late access and early retrieval capability, ITR increases the flexibility concerning transport capabilities to and from the ISS. RIST is our multi-functional test facility for ISPR-based experiment drawer and locker payloads. The test program concentrates on physical and functional interface and performance testing at the payload developers site prior to the shipment to the integration and launch. The RIST service program comprises consulting, planning and engineering as well. The RIST test suitcase is planned to be available for lease or rent to users, too. AMTSS is an advanced multimedia terminal consulting service for communication with the space station scientific facilities, as part of the user home-base. This unique ISS multimedia kit combines

  13. Optimized mine ventilation on demand (OMVOD)

    International Nuclear Information System (INIS)

    Anderson, M.

    2009-01-01

    This paper provided an overview of the Optimized Mine Ventilation on Demand (OMVOD) system that is being installed at Xstrata Nickel Rim South Project and at Vale Inco's Totten Mine in Sudbury. The OMVOD system is designed to dynamically monitor and control air quality and quantity in real time and dilute and remove hazardous substances including diesel particulate matter (DPM), carbon monoxide (CO) and nitrous oxide (NO 2 ). It is also designed to control the thermal environment and provide ventilation for humans as well as mobile equipment engine combustion according to regulatory standards. The paper highlighted the OMVOD system optimization of energy, air quality measurement and control and production management of the mines through real time dynamic automation. Topics of discussion included real-time tracking and monitoring of diesel equipment; real-time tracking of underground miners; real-time evaluation of mine ventilation networks; and real-time control and optimization of ventilation equipment. ABB and Simsmart Technologies have joined forces to provide underground mining customers with a ventilation optimization solution. Simsmart's OMVOD provides proven real time/dynamic automation technology to significantly reduce energy costs, provide health and safety benefits as well as major capital cost savings while realizing an increase in production.

  14. Optimized ventilation-on-demand (VOD)

    Energy Technology Data Exchange (ETDEWEB)

    Masse, M. [Simsmart Technologies Inc., Brossard, PQ (Canada); Cervinka, A. [Newtrax Technologies Inc., Montreal, PQ (Canada)

    2008-07-01

    This presentation described how the combination of 2 innovative technologies can help optimize mine ventilation. Newtrax Technologies has developed a self-contained battery-powered wireless electronic system designed to operate in harsh industrial environments, including underground mines. Simsmart Technologies has created an advanced process and control simulation based design tool used in industrial applications, including mine ventilation systems. This presentation described the system components and how they work. These included the wireless mesh network designed for dynamic diesel machinery tracking and operating status monitoring; the real-time ventilation model and fan speed optimizer; the OPC server for information interchange; the OPC linkage to existing control infrastructure; a human machine interface that provide data archiving capability; live MS-Excel to interrogate the simulation, controls and optimizer; and, the battery-powered network mesh that provides SCADA functionality to route optimized setpoints. Details of the user interface were also provided. 1 tab., 20 figs.

  15. Energy Efficient Routing in Nomadic Networks

    DEFF Research Database (Denmark)

    Kristensen, Mads Darø; Bouvin, Niels Olof

    2007-01-01

    We present an evaluation of a novel energy-efficient routing protocol for mobile ad-hoc networks. We combine two techniques for optimizing energy levels with a well-known routing protocol. We examine the behavior of this combination in a nomadic network setting, where some nodes are stationary...

  16. Ventilation on demand (VOD) projects : Vale Inco Ltd.

    Energy Technology Data Exchange (ETDEWEB)

    Allen, C.L. [Vale Inco Ltd., Sudbury, ON (Canada)

    2008-07-01

    This paper presented a dynamic ventilation on Demand (VOD) system that is in the developmental stages at Vale Inco. The VOD addresses the need to minimize ventilation costs associated with mining at depth. The physical components of the system are in the process of being tested at Vale Inco's mine sites in Sudbury, Ontario, where the company operates 6 base metal mines that vary in depth from 1200 metres to 2400 metres. Two pilot projects are simultaneously testing the physical components of the VOD system at Coleman and Creighton mines. A Scope of Work is also being finalized in which the architecture of the system is being optimized for testing a prototype dynamic VOD installation. The primary ventilation systems at the mines were described along with future ventilation requirements and air flow regulations with reference to both conventional and automated regulators. The development of the VOD system involved software development, computer networking, electrical planning, PLC programming and accurate ventilation modeling. The common objective was to reduce ventilation cost and increase production in the mine by maximizing the efficiency of the ventilation system. This will be accomplished through communication training and following safety standards and protocols. 7 refs., 2 tabs., 6 figs.

  17. Efficient network resource management for multimedia-on-demand services

    Science.gov (United States)

    Kuo, Chinhwa; Chiu, Jui-Hwa; Wu, Jong-Jyh; Chen, Dxo-Shin

    1998-08-01

    A Multimedia Instruction on Demand (MID) serves the purpose of providing an environment for lecture design, lecture annotation, and lecture review over networks. In order to support real-time multimedia interactive playback for such an application, the underlying networks are required to provide network resource management mechanism to enforce the reservation policy. In our design, the MID server and MID gateway consist of the following mechanisms, namely, resource management agent, admission control agent, packet classifier, and packet scheduler. We make use of the framework of the ReSerVation Protocol to devise and implement a network resource management mechanism, which control end-to-end packet delays and bandwidth allocation for the designed MID system. In the present paper, our contributions are as follows: (1) a network resource management scheme is designed to support real-time multimedia over the Internet and (2) an experimental test bed is established to measure the system performance. The developed scheme is currently being implemented in the Multimedia Information Networking laboratory at Tamkang University.

  18. Whirlpool routing for mobility

    KAUST Repository

    Lee, Jung Woo

    2010-01-01

    We present the Whirlpool Routing Protocol (WARP), which efficiently routes data to a node moving within a static mesh. The key insight in WARP\\'s design is that data traffic can use an existing routing gradient to efficiently probe the topology, repair the routing gradient, and communicate these repairs to nearby nodes. Using simulation, controlled testbeds, and real mobility experiments, we find that using the data plane for topology maintenance is highly effective due to the incremental nature of mobility updates. WARP leverages the fact that converging flows at a destination make the destination have the region of highest traffic. We provide a theoretical basis for WARP\\'s behavior, defining an "update area" in which the topology must adjust when a destination moves. As long as packets arrive at a destination before it moves outside of the update area, WARP can repair the topology using the data plane. Compared to existing protocols, such as DYMO and HYPER, WARP\\'s packet drop rate is up to 90% lower while sending up to 90% fewer packets.

  19. Routing Data Authentication in Wireless Networks; TOPICAL

    International Nuclear Information System (INIS)

    TORGERSON, MARK D.; VAN LEEUWEN, BRIAN P.

    2001-01-01

    In this paper, we discuss several specific threats directed at the routing data of an ad hoc network. We address security issues that arise from wrapping authentication mechanisms around ad hoc routing data. We show that this bolt-on approach to security may make certain attacks more difficult, but still leaves the network routing data vulnerable. We also show that under a certain adversarial model, most existing routing protocols cannot be secured with the aid of digital signatures

  20. Intrinsic motivation and organizational identification among on-demand workers.

    Science.gov (United States)

    Rockmann, Kevin W; Ballinger, Gary A

    2017-09-01

    On-demand firms provide services for clients through a network of on-demand workers ready to complete specific tasks for a set contractual price. Given such on-demand work is defined by payment on short-term contracts with no obligation for continued employment, there is little reason to believe on-demand workers experience more than extrinsic motivation and a transactional relationship with the on-demand firm. However, using self-determination theory, we argue that to the degree that on-demand work fulfills innate psychological needs individual on-demand workers will develop intrinsic motivation, which further leads to organizational identification with the on-demand firm. Across 2 survey-based studies we find support for this path to organizational identification. This adds to the literature on motivation and identification by strengthening the link between individual needs and the individual-organizational relationship. Implications for theory and for the management of on-demand workers are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. Route Flap Damping Made Usable

    Science.gov (United States)

    Pelsser, Cristel; Maennel, Olaf; Mohapatra, Pradosh; Bush, Randy; Patel, Keyur

    The Border Gateway Protocol (BGP), the de facto inter-domain routing protocol of the Internet, is known to be noisy. The protocol has two main mechanisms to ameliorate this, MinRouteAdvertisementInterval (MRAI), and Route Flap Damping (RFD). MRAI deals with very short bursts on the order of a few to 30 seconds. RFD deals with longer bursts, minutes to hours. Unfortunately, RFD was found to severely penalize sites for being well-connected because topological richness amplifies the number of update messages exchanged. So most operators have disabled it. Through measurement, this paper explores the avenue of absolutely minimal change to code, and shows that a few RFD algorithmic constants and limits can be trivially modified, with the result being damping a non-trivial amount of long term churn without penalizing well-behaved prefixes' normal convergence process.

  2. Analyzing the Effect of Passenger-Requested Unscheduled Stops on Demand

    Directory of Open Access Journals (Sweden)

    Dejan Paliska

    2007-07-01

    Full Text Available This paper discusses the effect of unscheduled stops requestedby passengers on bus transit demand and presents theresults of its study. In the research a set of regression modelsthat estimate the route-level demand were developed using datacollected with Automatic Passenger Counters and AutomaticVehicle Location systems installed on buses, and demographic,socio-economic and land use information from other sources.The results obtained indicate that the number of rider-requestedunscheduled stops have no significant effect on demand,suggesting that the company policy which tolerates unscheduledstops is inadequate for attracting new riders.

  3. Access control for on-demand provisioned cloud infrastructure services

    NARCIS (Netherlands)

    Ngo, C.T.

    2016-01-01

    The evolution of Cloud Computing brings advantages to both customers and service providers to utilize and manage computing and network resources more efficiently with virtualization, service-oriented architecture technologies, and automated on-demand resource provisioning. However, these advantages

  4. On-Demand Special Use Airspace, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We design and develope a Decision Support Tool (DST) that supports On-Demand Special Use Airspace (SUA) scheduling and flight plan optimization around SUA between...

  5. On-Demand Special Use Airspace, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We design and develop a Decision Support Tool (DST) that supports On-Demand Special Use Airspace (SUA) scheduling and flight plan optimization around SUA between...

  6. DESIGN OF ENERGY EFFICIENT ROUTING ALGORITHM FOR WIRELESS SENSOR NETWORK (WSN) USING PASCAL GRAPH

    OpenAIRE

    Deepali Panwar; Subhrendu Guha Neogi

    2013-01-01

    Development of energy efficient Wireless Sensor Network (WSN) routing protocol is nowadays main area of interest amongst researchers. This research is an effort in designing energy efficient Wireless Sensor Network (WSN) routing protocol under certain parameters consideration. Research report discusses various existing WSN routing protocols and propose a new WSN energy efficient routing protocol. Results show a significant improvement in life cycle of the nodes and enhancement ...

  7. Scripted Mobile Network Routing in a Contested Environment

    National Research Council Canada - National Science Library

    Otto, Anthony R

    2008-01-01

    Mobile wireless network protocols currently run on optimistic routing algorithms, adjusting node connectivity only when the chosen connectivity metrics, such as signal strength, pass beyond minimum thresholds...

  8. Comparison of routing metrics for wireless mesh networks

    CSIR Research Space (South Africa)

    Nxumalo, SL

    2011-09-01

    Full Text Available in each and every relay node so as to find the next hop for the packet. A routing metric is simply a measure used for selecting the best path, used by a routing protocol. Figure 2 shows the relationship between a routing protocol and the routing... on its QoS-awareness level. The routing metrics that considered QoS the most were selected from each group. This section discusses the four routing metrics that were compared in this paper, which are: hop count (HOP), expected transmission count (ETX...

  9. Sinkhole Avoidance Routing in Wireless Sensor Networks

    Science.gov (United States)

    2011-05-09

    COVERED (From- To) 09-05-2011 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Sinkhole Avoidance Routing in Wireless Sensor Networks 5b . GRANT NUMBER . 5c...reliability of wireless sensor networks. 15. SUBJECT TERMS wireless sensor networks, sinkhole attack, routing protocol 16. SECURITY CLASSIFICATION...Include area code) Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std . Z39.18 1 Sinkhole Avoidance Routing in Wireless Sensor Networks MIDN 1/C

  10. Routing in Wireless Multimedia Home Networks

    NARCIS (Netherlands)

    Scholten, Johan; Jansen, P.G.; Hop, Laurens

    This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless real-time home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

  11. Routing in Wireless Multimedia Home Networks

    NARCIS (Netherlands)

    Scholten, Johan; Jansen, P.G.; Hop, Laurens

    This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless ¿real-time¿ home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

  12. The Design of Passive Optical Networking+Ethernet over Coaxial Cable Access Networking and Video-on-Demand Services Carrying

    Science.gov (United States)

    Ji, Wei

    2013-07-01

    Video on demand is a very attractive service used for entertainment, education, and other purposes. The design of passive optical networking+Ethernet over coaxial cable accessing and a home gateway system is proposed. The network integrates the passive optical networking and Ethernet over coaxial cable to provide high dedicated bandwidth for the metropolitan video-on-demand services. Using digital video broadcasting, IP television protocol, unicasting, and broadcasting mechanisms maximizes the system throughput. The home gateway finishes radio frequency signal receiving and provides three kinds of interfaces for high-definition video, voice, and data, which achieves triple-play and wire/wireless access synchronously.

  13. A Source Anonymity-Based Lightweight Secure AODV Protocol for Fog-Based MANET.

    Science.gov (United States)

    Fang, Weidong; Zhang, Wuxiong; Xiao, Jinchao; Yang, Yang; Chen, Wei

    2017-06-17

    Fog-based MANET (Mobile Ad hoc networks) is a novel paradigm of a mobile ad hoc network with the advantages of both mobility and fog computing. Meanwhile, as traditional routing protocol, ad hoc on-demand distance vector (AODV) routing protocol has been applied widely in fog-based MANET. Currently, how to improve the transmission performance and enhance security are the two major aspects in AODV's research field. However, the researches on joint energy efficiency and security seem to be seldom considered. In this paper, we propose a source anonymity-based lightweight secure AODV (SAL-SAODV) routing protocol to meet the above requirements. In SAL-SAODV protocol, source anonymous and secure transmitting schemes are proposed and applied. The scheme involves the following three parts: the source anonymity algorithm is employed to achieve the source node, without being tracked and located; the improved secure scheme based on the polynomial of CRC-4 is applied to substitute the RSA digital signature of SAODV and guarantee the data integrity, in addition to reducing the computation and energy consumption; the random delayed transmitting scheme (RDTM) is implemented to separate the check code and transmitted data, and achieve tamper-proof results. The simulation results show that the comprehensive performance of the proposed SAL-SAODV is a trade-off of the transmission performance, energy efficiency, and security, and better than AODV and SAODV.

  14. A multifunctional multimaterial system for on-demand protein release.

    Science.gov (United States)

    Tuncaboylu, Deniz Ceylan; Friess, Fabian; Wischke, Christian; Lendlein, Andreas

    2018-06-15

    In order to provide best control of the regeneration process for each individual patient, the release of protein drugs administered during surgery may need to be timely adapted and/or delayed according to the progress of healing/regeneration. This study aims to establish a multifunctional implant system for a local on-demand release, which is applicable for various types of proteins. It was hypothesized that a tubular multimaterial container kit, which hosts the protein of interest as a solution or gel formulation, would enable on-demand release if equipped with the capacity of diameter reduction upon external stimulation. Using devices from poly(ɛ-caprolactone) networks, it could be demonstrated that a shape-memory effect activated by heat or NIR light enabled on-demand tube shrinkage. The decrease of diameter of these shape-memory tubes (SMT) allowed expelling the payload as demonstrated for several proteins including SDF-1α, a therapeutically relevant chemotactic protein, to achieve e.g. continuous release with a triggered add-on dosing (open tube) or an on-demand onset of bolus or sustained release (sealed tube). Considering the clinical relevance of protein factors in (stem) cell attraction to lesions and the progress in monitoring biomarkers in body fluids, such on-demand release systems may be further explored e.g. in heart, nerve, or bone regeneration in the future. Copyright © 2018. Published by Elsevier B.V.

  15. Energy Efficient MANET Routing Using a Combination of Span and BECA/AFECA

    DEFF Research Database (Denmark)

    Kristensen, Mads Darø; Bouvin, Niels Olof

    2008-01-01

    This paper presents some novel approaches for energy efficient routing in mobile ad-hoc networks. Two known energy preserving techniques, Span and BECA/AFECA, are combined with a well-known re-active routing protocol, AODV, to create a new energy efficient routing protocol. Furthermore, the proto......This paper presents some novel approaches for energy efficient routing in mobile ad-hoc networks. Two known energy preserving techniques, Span and BECA/AFECA, are combined with a well-known re-active routing protocol, AODV, to create a new energy efficient routing protocol. Furthermore...

  16. Scalable video on demand adaptive Internet-based distribution

    CERN Document Server

    Zink, Michael

    2013-01-01

    In recent years, the proliferation of available video content and the popularity of the Internet have encouraged service providers to develop new ways of distributing content to clients. Increasing video scaling ratios and advanced digital signal processing techniques have led to Internet Video-on-Demand applications, but these currently lack efficiency and quality. Scalable Video on Demand: Adaptive Internet-based Distribution examines how current video compression and streaming can be used to deliver high-quality applications over the Internet. In addition to analysing the problems

  17. VuFind: eBooks on Demand Suchmaschine

    OpenAIRE

    Gstrein, Silvia

    2011-01-01

    The eBooks-on-Demand (EOD) network provides a trans-European digital document delivery service for end-users from all over the world offering digitization on demand of the public domain holdings of participating libraries. Currently the EOD network comprises over 30 libraries from 12 European countries. The service is offered through „EOD buttons“ placed at each record in the different library catalogues. Already in the first years of the service a common interface to search for all books off...

  18. Load Balancing Routing with Bounded Stretch

    Directory of Open Access Journals (Sweden)

    Chen Siyuan

    2010-01-01

    Full Text Available Routing in wireless networks has been heavily studied in the last decade. Many routing protocols are based on classic shortest path algorithms. However, shortest path-based routing protocols suffer from uneven load distribution in the network, such as crowed center effect where the center nodes have more load than the nodes in the periphery. Aiming to balance the load, we propose a novel routing method, called Circular Sailing Routing (CSR, which can distribute the traffic more evenly in the network. The proposed method first maps the network onto a sphere via a simple stereographic projection, and then the route decision is made by a newly defined "circular distance" on the sphere instead of the Euclidean distance in the plane. We theoretically prove that for a network, the distance traveled by the packets using CSR is no more than a small constant factor of the minimum (the distance of the shortest path. We also extend CSR to a localized version, Localized CSR, by modifying greedy routing without any additional communication overhead. In addition, we investigate how to design CSR routing for 3D networks. For all proposed methods, we conduct extensive simulations to study their performances and compare them with global shortest path routing or greedy routing in 2D and 3D wireless networks.

  19. An On-Demand Emergency Packet Transmission Scheme for Wireless Body Area Networks.

    Science.gov (United States)

    Al Ameen, Moshaddique; Hong, Choong Seon

    2015-12-04

    The rapid developments of sensor devices that can actively monitor human activities have given rise to a new field called wireless body area network (BAN). A BAN can manage devices in, on and around the human body. Major requirements of such a network are energy efficiency, long lifetime, low delay, security, etc. Traffic in a BAN can be scheduled (normal) or event-driven (emergency). Traditional media access control (MAC) protocols use duty cycling to improve performance. A sleep-wake up cycle is employed to save energy. However, this mechanism lacks features to handle emergency traffic in a prompt and immediate manner. To deliver an emergency packet, a node has to wait until the receiver is awake. It also suffers from overheads, such as idle listening, overhearing and control packet handshakes. An external radio-triggered wake up mechanism is proposed to handle prompt communication. It can reduce the overheads and improve the performance through an on-demand scheme. In this work, we present a simple-to-implement on-demand packet transmission scheme by taking into considerations the requirements of a BAN. The major concern is handling the event-based emergency traffic. The performance analysis of the proposed scheme is presented. The results showed significant improvements in the overall performance of a BAN compared to state-of-the-art protocols in terms of energy consumption, delay and lifetime.

  20. An On-Demand Emergency Packet Transmission Scheme for Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Moshaddique Al Ameen

    2015-12-01

    Full Text Available The rapid developments of sensor devices that can actively monitor human activities have given rise to a new field called wireless body area network (BAN. A BAN can manage devices in, on and around the human body. Major requirements of such a network are energy efficiency, long lifetime, low delay, security, etc. Traffic in a BAN can be scheduled (normal or event-driven (emergency. Traditional media access control (MAC protocols use duty cycling to improve performance. A sleep-wake up cycle is employed to save energy. However, this mechanism lacks features to handle emergency traffic in a prompt and immediate manner. To deliver an emergency packet, a node has to wait until the receiver is awake. It also suffers from overheads, such as idle listening, overhearing and control packet handshakes. An external radio-triggered wake up mechanism is proposed to handle prompt communication. It can reduce the overheads and improve the performance through an on-demand scheme. In this work, we present a simple-to-implement on-demand packet transmission scheme by taking into considerations the requirements of a BAN. The major concern is handling the event-based emergency traffic. The performance analysis of the proposed scheme is presented. The results showed significant improvements in the overall performance of a BAN compared to state-of-the-art protocols in terms of energy consumption, delay and lifetime.

  1. Robust against route failure using power proficient reliable routing in MANET

    Directory of Open Access Journals (Sweden)

    M. Malathi

    2018-03-01

    Full Text Available The aim of this paper was to propose a novel routing protocol for Mobile Adhoc Network communication which reduces the route failure during transmission. The proposed routing protocol uses 3 salient parameters to discover the path which ensure the reliable communication. The quality of the channel, link quality and energy level of the node are the major reasons for unintentional node failure in mobile Adhoc network. So the proposed routing protocol considers these three parameters to select the best forwarder node in the path. The reliable data communication is achieved by transmitting data via path selected by the proposed routing scheme has been proven using network simulator (NS2. Keywords: Channel quality, Link quality, Mobile Adhoc Network (MANET, Residual energy

  2. Scaling architecture-on-demand based optical networks

    NARCIS (Netherlands)

    Meyer, Hugo; Sancho, Jose Carlos; Mrdakovic, Milica; Peng, Shuping; Simeonidou, Dimitra; Miao, Wang; Calabretta, Nicola

    2016-01-01

    This paper analyzes methodologies that allow scaling properly Architecture-On-Demand (AoD) based optical networks. As Data Centers and HPC systems are growing in size and complexity, optical networks seem to be the way to scale the bandwidth of current network infrastructures. To scale the number of

  3. Security framework for virtualised infrastructure services provisioned on-demand

    NARCIS (Netherlands)

    Ngo, C.; Membrey, P.; Demchenko, Y.; de Laat, C.

    2011-01-01

    Cloud computing is developing as a new wave of ICT technologies, offering a common approach to on-demand provisioning computation, storage and network resources which are generally referred to as infrastructure services. Most of currently available commercial Cloud services are built and organized

  4. Magnetically induced localized on-demand drug delivery

    NARCIS (Netherlands)

    Rovers, S.A.

    2010-01-01

    Externally triggered on-demand drug release from an implant can significantly improve the efficiency of the drug therapy since it enables the patient or physician to control the dosing to the patient’s needs and releases the drug only at the required location in the human body. Therefore, patient

  5. Security Services Lifecycle Management in on-demand infrastructure services

    NARCIS (Netherlands)

    Demchenko, Y.; de Laat, C.; Lopez, D.R.; García-Espín, J.A.; Qiu, J.; Zhao, G.; Rong, C.

    2010-01-01

    Modern e-Science and high technology industry require high-performance and complicated network and computer infrastructure to support distributed collaborating groups of researchers and applications that should be provisioned on-demand. The effective use and management of the dynamically provisioned

  6. A digital laser for on-demand laser modes

    CSIR Research Space (South Africa)

    Ngcobo, S

    2013-08-01

    Full Text Available -cavity digitally addressed holographic mirror. The phase and amplitude of the holographic mirror may be controlled simply by writing a computer- generated hologram in the form of a grey-scale image to the device, for on-demand laser modes. We show that we can...

  7. Security infrastructure for on-demand provisioned Cloud infrastructure services

    NARCIS (Netherlands)

    Demchenko, Y.; Ngo, C.; de Laat, C.; Wlodarczyk, T.W.; Rong, C.; Ziegler, W.

    2011-01-01

    Providing consistent security services in on-demand provisioned Cloud infrastructure services is of primary importance due to multi-tenant and potentially multi-provider nature of Clouds Infrastructure as a Service (IaaS) environment. Cloud security infrastructure should address two aspects of the

  8. Trusted Virtual Infrastructure Bootstrapping for On Demand Services

    NARCIS (Netherlands)

    Membrey, P.; Chan, K.C.C.; Ngo, C.; Demchenko, Y.; de Laat, C.

    2012-01-01

    As cloud computing continues to gain traction, a great deal of effort is being expended in researching the most effective ways to build and manage secure and trustworthy clouds. Providing consistent security services in on-demand provisioned Cloud infrastructure services is of primary importance due

  9. A primer on on-demand polymerase chain reaction technology.

    Science.gov (United States)

    Spencer, Maureen; Barnes, Sue; Parada, Jorge; Brown, Scott; Perri, Luci; Uettwiller-Geiger, Denise; Johnson, Helen Boehm; Graham, Denise

    2015-10-01

    Efforts to reduce health care-associated infections (HAIs) have grown in both scale and sophistication over the past few decades; however, the increasing threat of antimicrobial resistance and the impact of new legislation regarding HAIs on health care economics make the fight against them all the more urgent. On-demand polymerase chain reaction (PCR) technology has proven to be a highly effective weapon in this fight, offering the ability to accurately and efficiently identify disease-causing pathogens such that targeted and directed therapy can be initiated at the point of care. As a result, on-demand PCR technology has far-reaching influences on HAI rates, health care outcomes, hospital length of stay, isolation days, patient satisfaction, antibiotic stewardship, and health care economics. The basics of on-demand PCR technology and its potential to impact health care have not been widely incorporated into health care education and enrichment programs for many of those involved in infection control and prevention, however. This article serves as a primer on on-demand PCR technology and its ramifications. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  10. 3VSR: Three Valued Secure Routing for Vehicular Ad Hoc Networks using Sensing Logic in Adversarial Environment

    Directory of Open Access Journals (Sweden)

    Muhammad Sohail

    2018-03-01

    Full Text Available Today IoT integrate thousands of inter networks and sensing devices e.g., vehicular networks, which are considered to be challenging due to its high speed and network dynamics. The goal of future vehicular networks is to improve road safety, promote commercial or infotainment products and to reduce the traffic accidents. All these applications are based on the information exchange among nodes, so not only reliable data delivery but also the authenticity and credibility of the data itself are prerequisite. To cope with the aforementioned problem, trust management come up as promising candidate to conduct node’s transaction and interaction management, which requires distributed mobile nodes cooperation for achieving design goals. In this paper, we propose a trust-based routing protocol i.e., 3VSR (Three Valued Secure Routing, which extends the widely used AODV (Ad hoc On-demand Distance Vector routing protocol and employs the idea of Sensing Logic-based trust model to enhance the security solution of VANET (Vehicular Ad-Hoc Network. The existing routing protocol are mostly based on key or signature-based schemes, which off course increases computation overhead. In our proposed 3VSR, trust among entities is updated frequently by means of opinion derived from sensing logic due to vehicles random topologies. In 3VSR the theoretical capabilities are based on Dirichlet distribution by considering prior and posterior uncertainty of the said event. Also by using trust recommendation message exchange, nodes are able to reduce computation and routing overhead. The simulated results shows that the proposed scheme is secure and practical.

  11. 3VSR: Three Valued Secure Routing for Vehicular Ad Hoc Networks using Sensing Logic in Adversarial Environment.

    Science.gov (United States)

    Sohail, Muhammad; Wang, Liangmin

    2018-03-14

    Today IoT integrate thousands of inter networks and sensing devices e.g., vehicular networks, which are considered to be challenging due to its high speed and network dynamics. The goal of future vehicular networks is to improve road safety, promote commercial or infotainment products and to reduce the traffic accidents. All these applications are based on the information exchange among nodes, so not only reliable data delivery but also the authenticity and credibility of the data itself are prerequisite. To cope with the aforementioned problem, trust management come up as promising candidate to conduct node's transaction and interaction management, which requires distributed mobile nodes cooperation for achieving design goals. In this paper, we propose a trust-based routing protocol i.e., 3VSR (Three Valued Secure Routing), which extends the widely used AODV (Ad hoc On-demand Distance Vector) routing protocol and employs the idea of Sensing Logic-based trust model to enhance the security solution of VANET (Vehicular Ad-Hoc Network). The existing routing protocol are mostly based on key or signature-based schemes, which off course increases computation overhead. In our proposed 3VSR, trust among entities is updated frequently by means of opinion derived from sensing logic due to vehicles random topologies. In 3VSR the theoretical capabilities are based on Dirichlet distribution by considering prior and posterior uncertainty of the said event. Also by using trust recommendation message exchange, nodes are able to reduce computation and routing overhead. The simulated results shows that the proposed scheme is secure and practical.

  12. Adaptive Probabilistic Routing in Wireless Ad Hoc Networks

    OpenAIRE

    Hasan, Affaf; Liaqat, Ismail

    2013-01-01

    The goal of this thesis work is to analyze how design elements and wireless attributes affect opportunistic routing, and in this context develop a new protocol. The algorithm developed aims to improve opportunistic elements in comparison to a well-known opportunistic protocol Simple Opportunistic Adaptive Routing (SOAR).

  13. A Machine Learning Concept for DTN Routing

    Science.gov (United States)

    Dudukovich, Rachel; Hylton, Alan; Papachristou, Christos

    2017-01-01

    This paper discusses the concept and architecture of a machine learning based router for delay tolerant space networks. The techniques of reinforcement learning and Bayesian learning are used to supplement the routing decisions of the popular Contact Graph Routing algorithm. An introduction to the concepts of Contact Graph Routing, Q-routing and Naive Bayes classification are given. The development of an architecture for a cross-layer feedback framework for DTN (Delay-Tolerant Networking) protocols is discussed. Finally, initial simulation setup and results are given.

  14. Next Generation Network Routing and Control Plane

    DEFF Research Database (Denmark)

    Fu, Rong

    proved, the dominating Border Gateway Protocol (BGP) cannot address all the issues that in inter-domain QoS routing. Thus a new protocol or network architecture has to be developed to be able to carry the inter-domain traffic with the QoS and TE consideration. Moreover, the current network control also...... lacks the ability to cooperate between different domains and operators. The emergence of label switching transport technology such as of Multi-Protocol Label Switching (MPLS) or Generalized MPLS (GMPLS) supports the traffic transport in a finer granularity and more dedicated end-to-end Quality...... (RACF) provides the platform that enables cooperation and ubiquitous integration between networks. In this paper, we investigate in the network architecture, protocols and algorithms for inter-domain QoS routing and traffic engineering. The PCE based inter-domain routing architecture is enhanced...

  15. ASSESSMENT OF RIP-V1 AND OSPF-V2 PROTOCOL WITH CONSIDERATION OF CONVERGENCE CRITERIA AND SENDING PROTOCOLS TRAFFIC

    Directory of Open Access Journals (Sweden)

    Hamed Jelodar

    2014-03-01

    Full Text Available Routing Protocols are underlying principles in networks like internet, transport and mobile. Routing Protocols include a series of rules and algorithms that consider routing metric and select the best way for sending healthy data packets from origin to destination. Dynamic routing protocol compatible to topology has a changeable state. RIP and OSPF are dynamic routing protocol that we consider criteria like convergence and sending protocols traffic assessment RIP first version and OSPF second version. By the test we have done on OPNET stimulation we understood that the OSPF protocol was more efficient than RIP protocol.

  16. Satellite Communications Using Commercial Protocols

    Science.gov (United States)

    Ivancic, William D.; Griner, James H.; Dimond, Robert; Frantz, Brian D.; Kachmar, Brian; Shell, Dan

    2000-01-01

    NASA Glenn Research Center has been working with industry, academia, and other government agencies in assessing commercial communications protocols for satellite and space-based applications. In addition, NASA Glenn has been developing and advocating new satellite-friendly modifications to existing communications protocol standards. This paper summarizes recent research into the applicability of various commercial standard protocols for use over satellite and space- based communications networks as well as expectations for future protocol development. It serves as a reference point from which the detailed work can be readily accessed. Areas that will be addressed include asynchronous-transfer-mode quality of service; completed and ongoing work of the Internet Engineering Task Force; data-link-layer protocol development for unidirectional link routing; and protocols for aeronautical applications, including mobile Internet protocol routing for wireless/mobile hosts and the aeronautical telecommunications network protocol.

  17. On-demand Overlay Networks for Large Scientific Data Transfers

    Energy Technology Data Exchange (ETDEWEB)

    Ramakrishnan, Lavanya [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Guok, Chin [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jackson, Keith [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kissel, Ezra [Univ. of Delaware, Newark, DE (United States); Swany, D. Martin [Univ. of Delaware, Newark, DE (United States); Agarwal, Deborah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2009-10-12

    Large scale scientific data transfers are central to scientific processes. Data from large experimental facilities have to be moved to local institutions for analysis or often data needs to be moved between local clusters and large supercomputing centers. In this paper, we propose and evaluate a network overlay architecture to enable highthroughput, on-demand, coordinated data transfers over wide-area networks. Our work leverages Phoebus and On-demand Secure Circuits and AdvanceReservation System (OSCARS) to provide high performance wide-area network connections. OSCARS enables dynamic provisioning of network paths with guaranteed bandwidth and Phoebus enables the coordination and effective utilization of the OSCARS network paths. Our evaluation shows that this approach leads to improved end-to-end data transfer throughput with minimal overheads. The achievedthroughput using our overlay was limited only by the ability of the end hosts to sink the data.

  18. Health care on demand: four telehealth priorities for 2016.

    Science.gov (United States)

    Grube, Mark E; Kaufman, Kenneth; Clarin, Dan; O'Riordan, Jason

    2016-01-01

    Consumers who are accustomed to on-demand, virtual services are looking for more convenient ways to access health care. Giving patients the opportunity to connect with physicians remotely can promote higher patient satisfaction and engagement. Telehealth options may have a high start-up cost, but that cost is likely well-justified by the potential to enhance quality, outcomes, and customer attraction and satisfaction/retention over the long-term.

  19. Knowledge acquisition and interface design for learning on demand systems

    Science.gov (United States)

    Nelson, Wayne A.

    1993-01-01

    The rapid changes in our world precipitated by technology have created new problems and new challenges for education and training. A knowledge 'explosion' is occurring as our society moves toward a service oriented economy that relies on information as the major resource. Complex computer systems are beginning to dominate the workplace, causing alarming growth and change in many fields. The rapidly changing nature of the workplace, especially in fields related to information technology, requires that our knowledge be updated constantly. This characteristic of modern society poses seemingly unsolvable instructional problems involving coverage and obsolescence. The sheer amount of information to be learned is rapidly increasing, while at the same time some information becomes obsolete in light of new information. Education, therefore, must become a lifelong process that features learning of new material and skills as needed in relation to the job to be done. Because of the problems cited above, the current model of learning in advance may no longer be feasible in our high-technology world. In many cases, learning in advance is impossible because there are simply too many things to learn. In addition, learning in advance can be time consuming, and often results in decontextualized knowledge that does not readily transfer to the work environment. The large and growing discrepancy between the amount of potentially relevant knowledge available and the amount a person can know and remember makes learning on demand an important alternative to current instructional practices. Learning on demand takes place whenever an individual must learn something new in order to perform a task or make a decision. Learning on demand is a promising approach for addressing the problems of coverage and obsolescence because learning is contextualized and integrated into the task environment rather than being relegated to a separate phase that precedes work. Learning on demand allows learners

  20. Creation, Storage, and On-Demand Release of Optical Quantum States with a Negative Wigner Function

    Directory of Open Access Journals (Sweden)

    Jun-ichi Yoshikawa

    2013-12-01

    Full Text Available Highly nonclassical quantum states of light, characterized by Wigner functions with negative values, have been all-optically created so far only in a heralded fashion. In this case, the desired output emerges rarely and randomly from a quantum-state generator. An important example is the heralded production of high-purity single-photon states, typically based on some nonlinear optical interaction. In contrast, on-demand single-photon sources are also reported, exploiting the quantized level structure of matter systems. These sources, however, lead to highly impure output states, composed mostly of vacuum. While such impure states may still exhibit certain single-photon-like features such as antibunching, they are not nonclassical enough for advanced quantum-information processing. On the other hand, the intrinsic randomness of pure, heralded states can be circumvented by first storing and then releasing them on demand. Here, we propose such a controlled release, and we experimentally demonstrate it for heralded single photons. We employ two optical cavities, where the photons are both created and stored inside one cavity and finally released through a dynamical tuning of the other cavity. We demonstrate storage times of up to 300 ns while keeping the single-photon purity around 50% after storage. Our experiment is the first demonstration of a negative Wigner function at the output of an on-demand photon source or a quantum memory. In principle, our storage system is compatible with all kinds of nonclassical states, including those known to be essential for many advanced quantum-information protocols.

  1. Hurricane Evacuation Routes

    Data.gov (United States)

    Department of Homeland Security — Hurricane Evacuation Routes in the United States A hurricane evacuation route is a designated route used to direct traffic inland in case of a hurricane threat. This...

  2. A Preemptive Link State Spanning Tree Source Routing Scheme for Opportunistic Data Forwarding in MANET

    OpenAIRE

    R. Poonkuzhali; M. Y. Sanavullah; A. Sabari

    2014-01-01

    Opportunistic Data Forwarding (ODF) has drawn much attention in mobile adhoc networking research in recent years. The effectiveness of ODF in MANET depends on a suitable routing protocol which provides a powerful source routing services. PLSR is featured by source routing, loop free and small routing overhead. The update messages in PLSR are integrated into a tree structure and no need to time stamp routing updates which reduces the routing overhead.

  3. The Interest of Performing "On-Demand Chest X-rays" after Lung Resection by Minimally Invasive Surgery.

    Science.gov (United States)

    Haddad, Laura; Bubenheim, Michael; Bernard, Alain; Melki, Jean; Peillon, Christophe; Baste, Jean-Marc

    2017-10-01

    Background  There is a lack of consensus in hospital centers regarding costly daily routine chest X-rays after lung resection by minimally invasive surgery. Indeed, there is no evidence that performing daily chest X-rays prevents postoperative complications. Our objective was to compare chest X-rays performed on demand when there was clinical suspicion of postoperative complications and chest X-rays performed systematically in daily routine practice. Methods  This prospective single-center study compared 55 patients who had on-demand chest X-rays and patients in the literature who had daily routine chest X-rays. Our primary evaluation criterion was length of hospitalization. Results  The length of hospitalization was 5.3 ± 3.3 days for patients who had on-demand X-rays, compared with 4 to 9.7 days for patients who had daily routine X-rays. Time to chest tube removal (4.34 days), overall complication rate (27.2%), reoperation rate (3.6%), and mortality rate (1.8%) were comparable to those in the literature. On average, our patients only had 1.22 ± 1.8 on-demand X-rays, compared with 3.3 X-rays if daily routine protocol had been applied. Patients with complications had more X-rays (3.4 ± 1.8) than patients without complications (0.4 ± 0.7). Conclusion  On-demand chest X-rays do not seem to delay the diagnosis of postoperative complications or increase morbidity-mortality rates. Performing on-demand chest X-rays could not only simplify surgical practice but also have a positive impact on health care expenses. However, a broader randomized study is warranted to validate this work and ultimately lead to national consensus. Georg Thieme Verlag KG Stuttgart · New York.

  4. Sensor Management for Applied Research Technologies (SMART)-On Demand Modeling (ODM) Project

    Science.gov (United States)

    Goodman, M.; Blakeslee, R.; Hood, R.; Jedlovec, G.; Botts, M.; Li, X.

    2006-01-01

    NASA requires timely on-demand data and analysis capabilities to enable practical benefits of Earth science observations. However, a significant challenge exists in accessing and integrating data from multiple sensors or platforms to address Earth science problems because of the large data volumes, varying sensor scan characteristics, unique orbital coverage, and the steep learning curve associated with each sensor and data type. The development of sensor web capabilities to autonomously process these data streams (whether real-time or archived) provides an opportunity to overcome these obstacles and facilitate the integration and synthesis of Earth science data and weather model output. A three year project, entitled Sensor Management for Applied Research Technologies (SMART) - On Demand Modeling (ODM), will develop and demonstrate the readiness of Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE) capabilities that integrate both Earth observations and forecast model output into new data acquisition and assimilation strategies. The advancement of SWE-enabled systems (i.e., use of SensorML, sensor planning services - SPS, sensor observation services - SOS, sensor alert services - SAS and common observation model protocols) will have practical and efficient uses in the Earth science community for enhanced data set generation, real-time data assimilation with operational applications, and for autonomous sensor tasking for unique data collection.

  5. Simulation Framework for Rebalancing of Autonomous Mobility on Demand Systems

    Directory of Open Access Journals (Sweden)

    Marczuk Katarzyna A.

    2016-01-01

    This study is built upon our previous work on Autonomous Mobility on Demand (AMOD systems. Our methodology is simulation-based and we make use of SimMobility, an agent-based microscopic simulation platform. In the current work we focus on the framework for testing different rebalancing policies for the AMOD systems. We compare three different rebalancing methods: (i no rebalancing, (ii offline rebalancing, and (iii online rebalancing. Simulation results indicate that rebalancing reduces the required fleet size and shortens the customers’ wait time.

  6. First drop dissimilarity in drop-on-demand inkjet devices

    International Nuclear Information System (INIS)

    Famili, Amin; Palkar, Saurabh A.; Baldy, William J. Jr.

    2011-01-01

    As inkjet printing technology is increasingly applied in a broader array of applications, careful characterization of its method of use is critical due to its inherent sensitivity. A common operational mode in inkjet technology known as drop-on-demand ejection is used as a way to deliver a controlled quantity of material to a precise location on a target. This method of operation allows ejection of individual or a sequence (burst) of drops based on a timed trigger event. This work presents an examination of sequences of drops as they are ejected, indicating a number of phenomena that must be considered when designing a drop-on-demand inkjet system. These phenomena appear to be driven by differences between the first ejected drop in a burst and those that follow it and result in a break-down of the linear relationship expected between driving amplitude and drop mass. This first drop, as quantified by high-speed videography and subsequent image analysis, can be different in morphology, trajectory, velocity, and volume from subsequent drops within a burst. These findings were confirmed orthogonally by both volume and mass measurement techniques which allowed quantitation down to single drops.

  7. An Application of Path Sharing To Routing For Mobile Sinks In ...

    African Journals Online (AJOL)

    CODEXT protocol for optimizing routing to multiple sinks through reinforcement learning. Such a routing situation arises in WSNs with multiple, possibly mobile sinks, such as WSNs with actuators deployed in parallel to sensors. This protocol is based on GAF protocol and grid structure to reduce energy consumed.

  8. Applied Multiprotocol Routing in IP Telephony

    Directory of Open Access Journals (Sweden)

    Miroslav Voznak

    2010-01-01

    Full Text Available The aim of the project was to create a multi-protocol system using SIP, H.323 and MGCP standards, which would ensure routing to various types of VoIP networks. The priority was to provide multi-protocol support to SIP and H.323 signalling and the support of the routing using the ENUM standard which has recently passed from the trial phase into full operation in the Czech Republic. The document describes the system's architecture and the components used. It also briefly describes ENUM.

  9. OSPF-TE Extensions for Green Routing in Optical Networks

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Ricciardi, S.; Fagertun, Anna Manolova

    2012-01-01

    This paper proposes extensions to the OSPF-TE protocol to enable green routing in GMPLS-controlled optical networks. Simulation results show a remarkable reduction in CO2 emissions by preferring network elements powered by green energy sources in the connection routing.......This paper proposes extensions to the OSPF-TE protocol to enable green routing in GMPLS-controlled optical networks. Simulation results show a remarkable reduction in CO2 emissions by preferring network elements powered by green energy sources in the connection routing....

  10. Evaluate the interactive and reusable service in adaptive on demand applications

    OpenAIRE

    Hwang , Chyi-Wen

    2007-01-01

    In this paper, the researcher based on the open platforms and tools for personalized learning idea, with the “ Interactive & reusable” function in UI design model, directly dealing with Knowledge on demand (KOD) service from the aspect-oriented and object-oriented issue. Moreover, to propose the KOD combine with VOD (Video on Demand); AOD (Audio on Demand); COD (Course on Demand) and IOD (Information on Demand in Global index searching) in diversity of hypermedia metadata.

  11. Routing architecture and security for airborne networks

    Science.gov (United States)

    Deng, Hongmei; Xie, Peng; Li, Jason; Xu, Roger; Levy, Renato

    2009-05-01

    Airborne networks are envisioned to provide interconnectivity for terrestial and space networks by interconnecting highly mobile airborne platforms. A number of military applications are expected to be used by the operator, and all these applications require proper routing security support to establish correct route between communicating platforms in a timely manner. As airborne networks somewhat different from traditional wired and wireless networks (e.g., Internet, LAN, WLAN, MANET, etc), security aspects valid in these networks are not fully applicable to airborne networks. Designing an efficient security scheme to protect airborne networks is confronted with new requirements. In this paper, we first identify a candidate routing architecture, which works as an underlying structure for our proposed security scheme. And then we investigate the vulnerabilities and attack models against routing protocols in airborne networks. Based on these studies, we propose an integrated security solution to address routing security issues in airborne networks.

  12. Research on routing algorithm based on the VANET

    Directory of Open Access Journals (Sweden)

    AN Li

    2016-01-01

    Full Text Available For the characteristics of high speed mobility of nodes, frequent changes of dynamic topology and frequent interrupts of the communication links in the VANET, this paper analyzed the defect of the current mobile ad-hoc network routing protocol, and carried on the simulation analysis on the adaptability of AODV, DSR and DSDV routing protocols in VANET applications in the VANET. Through the above research, this paper obtained the conclusion that the AODV routing protocol is more suitable for vehicular ad hoc network environment

  13. A Smart Audio on Demand Application on Android Systems

    Directory of Open Access Journals (Sweden)

    Ing-Jr Ding

    2015-05-01

    Full Text Available This paper describes a study of the realization of intelligent Audio on Demand (AOD processing in the embedded system environment. This study describes the development of innovative Android software that will enhance user experience of the increasingly popular number of smart mobile devices now available on the market. The application we developed can accumulate records of the songs that are played and automatically analyze the favorite song types of a user. The application can also select sound control playback functions to make operation more convenient. A large number of different types of music genre were collected to create a sound database and build an intelligent AOD processing mechanism. Formant analysis was used to extract voice features and the K-means clustering method and acoustic modeling technology of the Gaussian mixture model (GMM were used to study and develop the application mechanism. The processes we developed run smoothly in the embedded Android platform.

  14. On-Demand Microwave Generator of Shaped Single Photons

    Science.gov (United States)

    Forn-Díaz, P.; Warren, C. W.; Chang, C. W. S.; Vadiraj, A. M.; Wilson, C. M.

    2017-11-01

    We demonstrate the full functionality of a circuit that generates single microwave photons on demand, with a wave packet that can be modulated with a near-arbitrary shape. We achieve such a high tunability by coupling a superconducting qubit near the end of a semi-infinite transmission line. A dc superconducting quantum interference device shunts the line to ground and is employed to modify the spatial dependence of the electromagnetic mode structure in the transmission line. This control allows us to couple and decouple the qubit from the line, shaping its emission rate on fast time scales. Our decoupling scheme is applicable to all types of superconducting qubits and other solid-state systems and can be generalized to multiple qubits as well as to resonators.

  15. On-Demand Cell Internal Short Circuit Device

    Science.gov (United States)

    Darcy, Eric; Keyser, Matthew

    2014-01-01

    A device implantable in Li-ion cells that can generate a hard internal short circuit on-demand by exposing the cell to 60?C has been demonstrated to be valuable for expanding our understanding of cell responses. The device provides a negligible impact to cell performance and enables the instigation of the 4 general categories of cell internal shorts to determine relative severity and cell design susceptibility. Tests with a 18650 cell design indicates that the anode active material short to the aluminum cathode current collector tends to be more catastrophic than the 3 other types of internal shorts. Advanced safety features (such as shutdown separators) to prevent or mitigate the severity of cell internal shorts can be verified with this device. The hard short success rate achieved to date in 18650 cells is about 80%, which is sufficient for using these cells in battery assemblies for field-failure-relevant, cell-cell thermal runaway propagation verification tests

  16. Adjusting process count on demand for petascale global optimization

    KAUST Repository

    Sosonkina, Masha; Watson, Layne T.; Radcliffe, Nicholas R.; Haftka, Rafael T.; Trosset, Michael W.

    2013-01-01

    There are many challenges that need to be met before efficient and reliable computation at the petascale is possible. Many scientific and engineering codes running at the petascale are likely to be memory intensive, which makes thrashing a serious problem for many petascale applications. One way to overcome this challenge is to use a dynamic number of processes, so that the total amount of memory available for the computation can be increased on demand. This paper describes modifications made to the massively parallel global optimization code pVTdirect in order to allow for a dynamic number of processes. In particular, the modified version of the code monitors memory use and spawns new processes if the amount of available memory is determined to be insufficient. The primary design challenges are discussed, and performance results are presented and analyzed.

  17. Advanced Continuous Flow Platform for On-Demand Pharmaceutical Manufacturing.

    Science.gov (United States)

    Zhang, Ping; Weeranoppanant, Nopphon; Thomas, Dale A; Tahara, Kohei; Stelzer, Torsten; Russell, Mary Grace; O'Mahony, Marcus; Myerson, Allan S; Lin, Hongkun; Kelly, Liam P; Jensen, Klavs F; Jamison, Timothy F; Dai, Chunhui; Cui, Yuqing; Briggs, Naomi; Beingessner, Rachel L; Adamo, Andrea

    2018-02-21

    As a demonstration of an alternative to the challenges faced with batch pharmaceutical manufacturing including the large production footprint and lengthy time-scale, we previously reported a refrigerator-sized continuous flow system for the on-demand production of essential medicines. Building on this technology, herein we report a second-generation, reconfigurable and 25 % smaller (by volume) continuous flow pharmaceutical manufacturing platform featuring advances in reaction and purification equipment. Consisting of two compact [0.7 (L)×0.5 (D)×1.3 m (H)] stand-alone units for synthesis and purification/formulation processes, the capabilities of this automated system are demonstrated with the synthesis of nicardipine hydrochloride and the production of concentrated liquid doses of ciprofloxacin hydrochloride, neostigmine methylsulfate and rufinamide that meet US Pharmacopeia standards. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. VINE ROUTES IN BULGARIA

    Directory of Open Access Journals (Sweden)

    Lyuben Hristov

    2015-03-01

    Full Text Available The article deals with a scheme for the modern vine route in Bulgaria. Five basic vine routes and one international, between Bulgaria, Macedonia and Greece are defined. All routes consider characteristic varieties of grapes and kinds of vine products. Vine tourist products combined with visits of important natural and anthropological object are in the bases of the defined routes. The described routes are an important contribution to development of alternative tourist products in the country.

  19. Mobility Tolerant Firework Routing for Improving Reachability in MANETs

    Directory of Open Access Journals (Sweden)

    Gen Motoyoshi

    2014-03-01

    Full Text Available In this paper, we investigate our mobility-assisted and adaptive broadcast routing mechanism, called Mobility Tolerant Firework Routing (MTFR, which utilizes the concept of potentials for routing and improves node reachability, especially in situations with high mobility, by including a broadcast mechanism. We perform detailed evaluations by simulations in a mobile environment and demonstrate the advantages of MTFR over conventional potential-based routing. In particular, we show that MTFR produces better reachability in many aspects at the expense of a small additional transmission delay and intermediate traffic overhead, making MTFR a promising routing protocol and feasible for future mobile Internet infrastructures.

  20. Targeted On-Demand Team Performance App Development

    Science.gov (United States)

    2018-02-01

    management protocols and set up file management using encryption and a secure server. Complete 10 Customize Data Collection App Modify CareAssess App to...greater team morale. An App that serves to build relationships around the management of emergency medicine cases over time, could stimulate the... Management 4. Casualty Care 5. Trauma Care 6. Critical Care 7. Trauma Management 8. High Performing Teams 9. Team Characteristics 10. Team Composition

  1. Routing in opportunistic networks

    CERN Document Server

    Dhurandher, Sanjay; Anpalagan, Alagan; Vasilakos, Athanasios

    2013-01-01

    This book provides a comprehensive guide to selected topics, both ongoing and emerging, in routing in OppNets. The book is edited by worldwide technical leaders, prolific researchers and outstanding academics, Dr. Isaac Woungang and co-editors, Dr. Sanjay Kumar Dhurandher, Prof. Alagan Anpalagan and Prof. Athanasios Vasilakos. Consisting of contributions from well known and high profile researchers and scientists in their respective specialties, the main topics that are covered in this book include mobility and routing, social-aware routing, context-based routing, energy-aware routing, incentive-aware routing, stochastic routing, modeling of intermittent connectivity, in both infrastructure and infrastructure-less OppNets. Key Features: Discusses existing and emerging techniques for routing in infrastructure and infrastructure-less OppNets. Provides a unified covering of otherwise disperse selected topics on routing in infrastructure and infrastructure-less OppNets.  Includes a set of PowerPoint slides and g...

  2. Simulation and Evaluation of CTP and Secure-CTP Protocols

    Directory of Open Access Journals (Sweden)

    P. Pecho

    2010-04-01

    Full Text Available The paper discusses characteristics and qualities of two routing protocols – Collection Tree Protocol and its secure modification. The original protocol, as well as other protocols for wireless sensors, solves only problems of ra- dio communication and limited resources. Our design of the secure protocol tries to solve also the essential security ob- jectives. For the evaluation of properties of our protocol in large networks, a TOSSIM simulator was used. Our effort was to show the influence of the modification of the routing protocol to its behavior and quality of routing trees. We have proved that adding security into protocol design does not necessarily mean higher demands for data transfer, power consumption or worse protocol efficiency. In the paper, we manifest that security in the protocol may be achieved with low cost and may offer similar performance as the original protocol.

  3. The QKD network: model and routing scheme

    Science.gov (United States)

    Yang, Chao; Zhang, Hongqi; Su, Jinhai

    2017-11-01

    Quantum key distribution (QKD) technology can establish unconditional secure keys between two communicating parties. Although this technology has some inherent constraints, such as the distance and point-to-point mode limits, building a QKD network with multiple point-to-point QKD devices can overcome these constraints. Considering the development level of current technology, the trust relaying QKD network is the first choice to build a practical QKD network. However, the previous research didn't address a routing method on the trust relaying QKD network in detail. This paper focuses on the routing issues, builds a model of the trust relaying QKD network for easily analysing and understanding this network, and proposes a dynamical routing scheme for this network. From the viewpoint of designing a dynamical routing scheme in classical network, the proposed scheme consists of three components: a Hello protocol helping share the network topology information, a routing algorithm to select a set of suitable paths and establish the routing table and a link state update mechanism helping keep the routing table newly. Experiments and evaluation demonstrates the validity and effectiveness of the proposed routing scheme.

  4. On demand processing of climate station sensor data

    Science.gov (United States)

    Wöllauer, Stephan; Forteva, Spaska; Nauss, Thomas

    2015-04-01

    Large sets of climate stations with several sensors produce big amounts of finegrained time series data. To gain value of this data, further processing and aggregation is needed. We present a flexible system to process the raw data on demand. Several aspects need to be considered to process the raw data in a way that scientists can use the processed data conveniently for their specific research interests. First of all, it is not feasible to pre-process the data in advance because of the great variety of ways it can be processed. Therefore, in this approach only the raw measurement data is archived in a database. When a scientist requires some time series, the system processes the required raw data according to the user-defined request. Based on the type of measurement sensor, some data validation is needed, because the climate station sensors may produce erroneous data. Currently, three validation methods are integrated in the on demand processing system and are optionally selectable. The most basic validation method checks if measurement values are within a predefined range of possible values. For example, it may be assumed that an air temperature sensor measures values within a range of -40 °C to +60 °C. Values outside of this range are considered as a measurement error by this validation method and consequently rejected. An other validation method checks for outliers in the stream of measurement values by defining a maximum change rate between subsequent measurement values. The third validation method compares measurement data to the average values of neighboring stations and rejects measurement values with a high variance. These quality checks are optional, because especially extreme climatic values may be valid but rejected by some quality check method. An other important task is the preparation of measurement data in terms of time. The observed stations measure values in intervals of minutes to hours. Often scientists need a coarser temporal resolution

  5. A novel insight into beaconless geo-routing

    KAUST Repository

    Bader, Ahmed; Abed-Meraim, Karim; Alouini, Mohamed-Slim

    2012-01-01

    Beaconless geo-routing protocols have been traditionally analyzed assuming equal communication ranges for the data and control packets. This is not true in reality, since the communication range is in practice function of the packet length. As a

  6. Product diffusion through on-demand information-seeking behaviour.

    Science.gov (United States)

    Riedl, Christoph; Bjelland, Johannes; Canright, Geoffrey; Iqbal, Asif; Engø-Monsen, Kenth; Qureshi, Taimur; Sundsøy, Pål Roe; Lazer, David

    2018-02-01

    Most models of product adoption predict S-shaped adoption curves. Here we report results from two country-scale experiments in which we find linear adoption curves. We show evidence that the observed linear pattern is the result of active information-seeking behaviour: individuals actively pulling information from several central sources facilitated by modern Internet searches. Thus, a constant baseline rate of interest sustains product diffusion, resulting in a linear diffusion process instead of the S-shaped curve of adoption predicted by many diffusion models. The main experiment seeded 70 000 (48 000 in Experiment 2) unique voucher codes for the same product with randomly sampled nodes in a social network of approximately 43 million individuals with about 567 million ties. We find that the experiment reached over 800 000 individuals with 80% of adopters adopting the same product-a winner-take-all dynamic consistent with search engine driven rankings that would not have emerged had the products spread only through a network of social contacts. We provide evidence for (and characterization of) this diffusion process driven by active information-seeking behaviour through analyses investigating (a) patterns of geographical spreading; (b) the branching process; and (c) diffusion heterogeneity. Using data on adopters' geolocation we show that social spreading is highly localized, while on-demand diffusion is geographically independent. We also show that cascades started by individuals who actively pull information from central sources are more effective at spreading the product among their peers. © 2018 The Authors.

  7. Vaccines 'on demand': science fiction or a future reality.

    Science.gov (United States)

    Ulmer, Jeffrey B; Mansoura, Monique K; Geall, Andrew J

    2015-02-01

    Self-amplifying mRNA vaccines are being developed as a platform technology with potential to be used for a broad range of targets. The synthetic production methods for their manufacture, combined with the modern tools of bioinformatics and synthetic biology, enable these vaccines to be produced rapidly from an electronic gene sequence. Preclinical proof of concept has so far been achieved for influenza, respiratory syncytial virus, rabies, Ebola, cytomegalovirus, human immunodeficiency virus and malaria. This editorial highlights the key milestones in the discovery and development of self-amplifying mRNA vaccines, and reviews how they might be used as a rapid response platform. The paper points out how future improvements in RNA vector design and non-viral delivery may lead to decreases in effective dose and increases in production capacity. The prospects for non-viral delivery of self-amplifying mRNA vaccines are very promising. Like other types of nucleic acid vaccines, these vaccines have the potential to draw on the positive attributes of live-attenuated vaccines while obviating many potential safety limitations. Hence, this approach could enable the concept of vaccines on demand as a rapid response to a real threat rather than the deployment of strategic stockpiles based on epidemiological predictions for possible threats.

  8. Reciprocity on Demand : Sharing and Exchanging Food in Northwestern Namibia.

    Science.gov (United States)

    Schnegg, Michael

    2015-09-01

    Two competing models concerning food transfers prominent in the anthropological literature conceptualize such transfers either as sharing or as exchange. Sharing is understood as situational transactions formed through demands and unconditional giving, whereas reciprocal exchange is understood in terms of networking and keeping score. I propose that the picture is more complicated than these classifications suggests. Drawing on data collected in Northwestern Namibia, I show that sharing and reciprocal exchange are dynamically interrelated in actual food transfers. As a local norm, people can demand food from anyone, and they are typically given food in response to a demand. However, in practice, food transfer networks emerge (N = 62) that are highly reciprocal and fit the exchange model much better. Although the sharing norm makes no restrictions on whom to ask, in practice people often turn to their neighbors. Interpersonal dynamics account for why some of those ties become strongly reciprocal and others do not. Under these circumstances, unconditional sharing, a norm that has been viewed as an alternative to exchange, can lead to reciprocity via reciprocity on demand.

  9. Analisa Perbandingan Quality Of Service (QoS) pada Jaringan Backbone Non-MPLS dengan Jaringan Backbone MPLS Menggunakan Routing Protocol OSPF di PT. Telekomunikasi Indonesia, Tbk. Witel Ridar Riau

    OpenAIRE

    Silaban, Nestor Hasudungan; Sari, Linna Oktaviana; Anhar, Anhar

    2015-01-01

    The development of telecommunications technology based on Internet Protocol (IP) is now growing with the competitiveness of the telecommunications company to improve the quality of service to consumers. It can be obtained by increasing the quality backbone network using Multi Protocol Label Switching (MPLS). MPLS is a new technology to forward the packet to the backbone network without changing the existing network structure. The main idea is to construct a replacement MPLS paths using label ...

  10. Electro-Active Polymers (EAPs: A Promising Route to Design Bio-Organic/Bioinspired Platforms with on Demand Functionalities

    Directory of Open Access Journals (Sweden)

    Vincenzo Guarino

    2016-05-01

    Full Text Available Through recent discoveries and new knowledge among correlations between molecular biology and materials science, it is a growing interest to design new biomaterials able to interact—i.e., to influence, to guide or to detect—with cells and their surrounding microenvironments, in order to better control biological phenomena. In this context, electro-active polymers (EAPs are showing great promise as biomaterials acting as an interface between electronics and biology. This is ascribable to the highly tunability of chemical/physical properties which confer them different conductive properties for various applicative uses (i.e., molecular targeting, biosensors, biocompatible scaffolds. This review article is divided into three parts: the first one is an overview on EAPs to introduce basic conductivity mechanisms and their classification. The second one is focused on the description of most common processes used to manipulate EAPs in the form of two-dimensional (2D and three-dimensional (3D materials. The last part addresses their use in current applications in different biomedical research areas including tissue engineering, biosensors and molecular delivery.

  11. Efficient Routing in Wireless Sensor Networks with Multiple Sessions

    OpenAIRE

    Dianjie Lu; Guijuan Zhang; Ren Han; Xiangwei Zheng; Hong Liu

    2014-01-01

    Wireless Sensor Networks (WSNs) are subject to node failures because of limited energy and link unreliability which makes the design of routing protocols in such networks a challenging task. The multipath routing scheme is an optimal alternative to address this problem which splits the traffic across multiple paths instead of routing all the traffic along a single path. However, using more paths introduces more contentions which degrade energy efficiency. The problem becomes even more difficu...

  12. Hazmat Routes (National)

    Data.gov (United States)

    Department of Transportation — The Federal Motor Carrier Safety Administration (FMCSA) Hazardous Material Routes (NTAD) were developed using the 2004 First Edition TIGER/Line files. The routes are...

  13. 76 FR 20892 - Prohibition Against Payment of Interest on Demand Deposits

    Science.gov (United States)

    2011-04-14

    ... Interest on Demand Deposits AGENCY: Board of Governors of the Federal Reserve System. ACTION: Notice of... proposed amendments that would repeal Regulation Q, Prohibition Against Payment of Interest on Demand... interest on demand deposits by institutions that are member banks of the Federal Reserve System set forth...

  14. Performansi Video on Demand (VOD) Pada Virtual Private Network (VPN) Menggunakan OpenVPN

    OpenAIRE

    Priyambudi, Henry Okta

    2013-01-01

    Multimedia streaming menggunakanmedia video, sebagai cara penyampaian informasi yanglebih baik dibandingkan dengan teks atau suara. Salahsatu jenis multimedia streaming adalah Video OnDemand (VOD). Pada sistem video on demand, file videotelah disimpan terlebih dahulu di dalam server. Clientmerequest file video yang diinginkan dan prosesstreaming dapat dilakukan.. Salah satu kelemahan darivideo on demand adalah tidak ada sistem authentifikasipada client. Setiap client dapat melakukan streaming...

  15. State alternative route designations

    International Nuclear Information System (INIS)

    1989-07-01

    Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a ''state routing agency,'' defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective

  16. Ball Bearings Equipped for In Situ Lubrication on Demand

    Science.gov (United States)

    Marchetti, Mario; Jones, William R., Jr.; Pepper, Stephen V.; Jansen, Mark; Predmore, Roamer

    2005-01-01

    In situ systems that provide fresh lubricants to ball/race contacts on demand have been developed to prolong the operational lives of ball bearings. These systems were originally intended to be incorporated into ball bearings in mechanisms that are required to operate in outer space for years, in conditions in which lubricants tend to deteriorate and/or evaporate. These systems may also be useful for similarly prolonging bearing lifetimes on Earth. Reservoirs have been among the means used previously to resupply lubricants. Lubricant- resupply reservoirs are bulky and add complexity to bearing assemblies. In addition, such a reservoir cannot be turned on or off as needed: it supplies lubricant continuously, often leading to an excess of lubricant in the bearing. A lubricator of the present type includes a porous ring cartridge attached to the inner or the outer ring of a ball bearing (see Figure 1). Oil is stored in the porous cartridge and is released by heating the cartridge: Because the thermal expansion of the oil exceeds that of the cartridge, heating causes the ejection of some oil. A metal film can be deposited on a face of the cartridge to serve as an electrical-resistance heater. The heater can be activated in response to a measured increase in torque that signals depletion of oil from the bearing/race contacts. Because the oil has low surface tension and readily wets the bearing-ring material, it spreads over the bearing ring and eventually reaches the ball/race contacts. The Marangoni effect (a surface-tension gradient associated with a temperature gradient) is utilized to enhance the desired transfer of lubricant to the ball/race contacts during heating. For a test, a ball bearing designed for use at low speed was assembled without lubricant and equipped with a porous-ring lubricator, the resistance heater of which consumed a power of less than 1 W when triggered on by a torque-measuring device. In the test, a load of 20 lb (.89 N) was applied and the

  17. Nucleic acid therapeutic carriers with on-demand triggered release.

    Science.gov (United States)

    Venkatesh, Siddarth; Wower, Jacek; Byrne, Mark E

    2009-09-01

    optimization of a rich toolbox of novel drug and gene delivery platforms. We anticipate further inquiry into nucleic acid based programmable on-demand switches and modulatory devices of exquisite sensitivity and control.

  18. Cost-utility analysis of immune tolerance induction therapy versus on-demand treatment with recombinant factor VII for hemophilia A with high titer inhibitors in Iran

    Directory of Open Access Journals (Sweden)

    Rasekh HR

    2011-11-01

    Full Text Available Hamid Reza Rasekh1, Ali Imani1, Mehran Karimi2, Mina Golestani11Shahid Beheshti University of Medical Sciences, Department of Pharmaceutical Management and Pharmacoeconomics, School of Pharmacy, Tehran, 2University of Shiraz Medical Sciences, Hematology Research Center, Shiraz, IranBackground: In developing countries, the treatment of hemophilia patients with inhibitors is presently the most challenging and serious issue in hemophilia management, direct costs of clotting factor concentrates accounting for >98% of the highest economic burden absorbed for the health care of patients in this setting. In the setting of chronic diseases, cost-utility analysis, which takes into account the beneficial effects of a given treatment/health care intervention in terms of health-related quality of life, is likely to be the most appropriate approach.Objective: The aim of this study was to assess the incremental cost-effectiveness ratios of immune tolerance induction (ITI therapy with plasma-derived factor VIII concentrates versus on-demand treatment with recombinant-activated FVIIa (rFVIIa in hemophilia A with high titer inhibitors from an Iranian Ministry of Health perspective.Methods: This study was based on the study of Knight et al, which evaluated the cost-effectiveness ratios of different treatments for hemophilia A with high-responding inhibitors. To adapt Knight et al's results to the Iranian context, a few clinical parameters were varied, and cost data were replaced with the corresponding Iranian estimates of resource use. The time horizon of the analysis was 10 years. One-way sensitivity analyses were performed, varying the cost of the clotting factor, the drug dose, and the administration frequency, to test the robustness of the analysis.Results: Comparison of the incremental cost-effectiveness ratios between the three ITI protocols and the on-demand regimen with rFVIIa shows that all three ITI protocols dominate the on-demand regimen with r

  19. High Speed Mobility Through On-Demand Aviation

    Science.gov (United States)

    Moore, Mark D.; Goodrich, Ken; Viken, Jeff; Smith, Jeremy; Fredericks, Bill; Trani, Toni; Barraclough, Jonathan; German, Brian; Patterson, Michael

    2013-01-01

    automobiles. ?? Community Noise: Hub and smaller GA airports are facing increasing noise restrictions, and while commercial airliners have dramatically decreased their community noise footprint over the past 30 years, GA aircraft noise has essentially remained same, and moreover, is located in closer proximity to neighborhoods and businesses. ?? Operating Costs: GA operating costs have risen dramatically due to average fuel costs of over $6 per gallon, which has constrained the market over the past decade and resulted in more than 50% lower sales and 35% less yearly operations. Infusion of autonomy and electric propulsion technologies can accomplish not only a transformation of the GA market, but also provide a technology enablement bridge for both larger aircraft and the emerging civil Unmanned Aerial Systems (UAS) markets. The NASA Advanced General Aviation Transport Experiments (AGATE) project successfully used a similar approach to enable the introduction of primary composite structures and flat panel displays in the 1990s, establishing both the technology and certification standardization to permit quick adoption through partnerships with industry, academia, and the Federal Aviation Administration (FAA). Regional and airliner markets are experiencing constant pressure to achieve decreasing levels of community emissions and noise, while lowering operating costs and improving safety. But to what degree can these new technology frontiers impact aircraft safety, the environment, operations, cost, and performance? Are the benefits transformational enough to fundamentally alter aircraft competiveness and productivity to permit much greater aviation use for high speed and On-Demand Mobility (ODM)? These questions were asked in a Zip aviation system study named after the Zip Car, an emerging car-sharing business model. Zip Aviation investigates the potential to enable new emergent markets for aviation that offer "more flexibility than the existing transportation solutions

  20. Tests of PROOF-on-Demand with ATLAS Prodsys2 and first experience with HTTP federation

    CERN Document Server

    Di Nardo, Roberto; Vilucchi, Elisabetta; Antonelli, Mario

    2015-01-01

    During the LHC Run-1, Grid resources in ATLAS have been managed by the PanDA and DQ2 systems. In order to meet the needs for the LHC Run-2, Prodsys2 and Rucio are used as the new ATLAS Workload and Data Management systems. The data are stored under various formats in ROOT files and end-user physicists have the choice to use either the ATHENA framework or directly ROOT. Within the ROOT data analysis framework it is possible to perform analysis of huge sets of ROOT files in parallel with PROOF on clusters of computers (usually organised in analysis facilities) or multi-core machines. In addition, PROOF-on-Demand (PoD) can be used to enable PROOF on top of an existing resource management system. In this work, we present the first performances obtained enabling PROOF-based analysis at CERN and in some of the Italian ATLAS Tier-2 sites within the new ATLAS workload system. Benchmark tests of data access with the httpd protocol, using also the httpd redirector, will be shown. We also present results on the startup ...

  1. ZERO: Probabilistic Routing for Deploy and Forget Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jose Carlos Pacho

    2010-09-01

    Full Text Available As Wireless Sensor Networks are being adopted by industry and agriculture for large-scale and unattended deployments, the need for reliable and energy-conservative protocols become critical. Physical and Link layer efforts for energy conservation are not mostly considered by routing protocols that put their efforts on maintaining reliability and throughput. Gradient-based routing protocols route data through most reliable links aiming to ensure 99% packet delivery. However, they suffer from the so-called ”hot spot” problem. Most reliable routes waste their energy fast, thus partitioning the network and reducing the area monitored. To cope with this ”hot spot” problem we propose ZERO a combined approach at Network and Link layers to increase network lifespan while conserving reliability levels by means of probabilistic load balancing techniques.

  2. Eco-sustainable routing in optical networks

    DEFF Research Database (Denmark)

    Ricciardi, Sergio; Wang, Jiayuan; Palmieri, Francesco

    2013-01-01

    infrastructures are now widely recognized to play a fundamental role in the emission of green-house gases (GHG) in the at- mosphere, signicantly aecting the environmental sustainability of new evolutions in network architectures as well as technological developments in communication devices. In this paper......, a novel eco-sustainable Routing and Wavelength Assignment (RWA) algorithm, based on shortest-path routing with an adaptive link weighting function relying on an extension of the OSPF-TE protocol to convey carbon footprint information, has been proposed to decrease the network ecological impact while...

  3. Using Sphinx to Improve Onion Routing Circuit Construction

    Science.gov (United States)

    Kate, Aniket; Goldberg, Ian

    This paper presents compact message formats for onion routing circuit construction using the Sphinx methodology developed for mixes. We significantly compress the circuit construction messages for three onion routing protocols that have emerged as enhancements to the Tor anonymizing network; namely, Tor with predistributed Diffie-Hellman values, pairing-based onion routing, and certificateless onion routing. Our new circuit constructions are also secure in the universal composability framework, a property that was missing from the original constructions. Further, we compare the performance of our schemes with their older counterparts as well as with each other.

  4. RFID-WSN integrated architecture for energy and delay- aware routing a simulation approach

    CERN Document Server

    Ahmed, Jameel; Tayyab, Muhammad; Nawaz, Menaa

    2015-01-01

    The book identifies the performance challenges concerning Wireless Sensor Networks (WSN) and Radio Frequency Identification (RFID) and analyzes their impact on the performance of routing protocols. It presents a thorough literature survey to identify the issues affecting routing protocol performance, as well as a mathematical model for calculating the end-to-end delays of the routing protocol ACQUIRE; a comparison of two routing protocols (ACQUIRE and DIRECTED DIFFUSION) is also provided for evaluation purposes. On the basis of the results and literature review, recommendations are made for better selection of protocols regarding the nature of the respective application and related challenges. In addition, this book covers a proposed simulator that integrates both RFID and WSN technologies. Therefore, the manuscript is divided in two major parts: an integrated architecture of smart nodes, and a power-optimized protocol for query and information interchange.

  5. Multipath Routing in Wireless Sensor Networks: Survey and Research Challenges

    Science.gov (United States)

    Radi, Marjan; Dezfouli, Behnam; Bakar, Kamalrulnizam Abu; Lee, Malrey

    2012-01-01

    A wireless sensor network is a large collection of sensor nodes with limited power supply and constrained computational capability. Due to the restricted communication range and high density of sensor nodes, packet forwarding in sensor networks is usually performed through multi-hop data transmission. Therefore, routing in wireless sensor networks has been considered an important field of research over the past decade. Nowadays, multipath routing approach is widely used in wireless sensor networks to improve network performance through efficient utilization of available network resources. Accordingly, the main aim of this survey is to present the concept of the multipath routing approach and its fundamental challenges, as well as the basic motivations for utilizing this technique in wireless sensor networks. In addition, we present a comprehensive taxonomy on the existing multipath routing protocols, which are especially designed for wireless sensor networks. We highlight the primary motivation behind the development of each protocol category and explain the operation of different protocols in detail, with emphasis on their advantages and disadvantages. Furthermore, this paper compares and summarizes the state-of-the-art multipath routing techniques from the network application point of view. Finally, we identify open issues for further research in the development of multipath routing protocols for wireless sensor networks. PMID:22368490

  6. Multipath routing in wireless sensor networks: survey and research challenges.

    Science.gov (United States)

    Radi, Marjan; Dezfouli, Behnam; Abu Bakar, Kamalrulnizam; Lee, Malrey

    2012-01-01

    A wireless sensor network is a large collection of sensor nodes with limited power supply and constrained computational capability. Due to the restricted communication range and high density of sensor nodes, packet forwarding in sensor networks is usually performed through multi-hop data transmission. Therefore, routing in wireless sensor networks has been considered an important field of research over the past decade. Nowadays, multipath routing approach is widely used in wireless sensor networks to improve network performance through efficient utilization of available network resources. Accordingly, the main aim of this survey is to present the concept of the multipath routing approach and its fundamental challenges, as well as the basic motivations for utilizing this technique in wireless sensor networks. In addition, we present a comprehensive taxonomy on the existing multipath routing protocols, which are especially designed for wireless sensor networks. We highlight the primary motivation behind the development of each protocol category and explain the operation of different protocols in detail, with emphasis on their advantages and disadvantages. Furthermore, this paper compares and summarizes the state-of-the-art multipath routing techniques from the network application point of view. Finally, we identify open issues for further research in the development of multipath routing protocols for wireless sensor networks.

  7. DIRECTIONAL OPPORTUNISTIC MECHANISM IN CLUSTER MESSAGE CRITICALITY LEVEL BASED ZIGBEE ROUTING

    OpenAIRE

    B.Rajeshkanna *1, Dr.M.Anitha 2

    2018-01-01

    The cluster message criticality level based zigbee routing(CMCLZOR) has been proposed for routing the cluster messages in wireless smart energy home area networks. It employs zigbee opportunistic shortcut tree routing(ZOSTR) and AODV individually for routing normal messages and highly critical messages respectively. ZOSTR allows the receiving nodes to compete for forwarding a packet with the priority of left-over hops rather than stating single next hop node like unicast protocols. Since it h...

  8. Energy Efficient Routing in Wireless Sensor Networks Through Balanced Clustering

    Directory of Open Access Journals (Sweden)

    Christos Douligeris

    2013-01-01

    Full Text Available The wide utilization of Wireless Sensor Networks (WSNs is obstructed by the severely limited energy constraints of the individual sensor nodes. This is the reason why a large part of the research in WSNs focuses on the development of energy efficient routing protocols. In this paper, a new protocol called Equalized Cluster Head Election Routing Protocol (ECHERP, which pursues energy conservation through balanced clustering, is proposed. ECHERP models the network as a linear system and, using the Gaussian elimination algorithm, calculates the combinations of nodes that can be chosen as cluster heads in order to extend the network lifetime. The performance evaluation of ECHERP is carried out through simulation tests, which evince the effectiveness of this protocol in terms of network energy efficiency when compared against other well-known protocols.

  9. A Joint Link and Channel Assignment Routing Scheme for Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    H.S.Zhao

    2013-12-01

    Full Text Available Cognitive radio (CR is a promising technology that enables opportunistic utilization of the temporarily vacant spectrum to mitigate the spectrum scarcity in wireless communications. Since secondary users (SUs should vacate the channel in use immediately after detecting the reappearances of primary users (PUs in cognitive radio networks (CRNs, the route reliability is a distinctive challenge for routing in CRNs. Furthermore, the throughput requirement of an SU session should be satisfied and it is always preferable to select a route with less negative influence on other current or latish sessions. To account for the route reliability challenge, we study the joint link and channel assignment routing problem for CRNs. It is formulated in a form of integer nonlinear programming (INLP, which is NP-hard, with the objective of minimizing the interference of a new route to other routes while providing route reliability and throughput guarantee. An on-demand route discovery algorithm is proposed to find reliable candidate paths, while a joint link and channel assignment routing algorithm with sequentially-connected-link coordination is proposed to choose the near-optimal route for improving the route reliability and minimizing negative influence. Simulation results demonstrate that the proposed algorithm achieves considerable improvement over existing schemes in both route reliability and throughput.

  10. 31 CFR 501.602 - Reports to be furnished on demand.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Reports to be furnished on demand. 501.602 Section 501.602 Money and Finance: Treasury Regulations Relating to Money and Finance... REGULATIONS Reports § 501.602 Reports to be furnished on demand. Every person is required to furnish under...

  11. Understanding individual routing behaviour.

    Science.gov (United States)

    Lima, Antonio; Stanojevic, Rade; Papagiannaki, Dina; Rodriguez, Pablo; González, Marta C

    2016-03-01

    Knowing how individuals move between places is fundamental to advance our understanding of human mobility (González et al. 2008 Nature 453, 779-782. (doi:10.1038/nature06958)), improve our urban infrastructure (Prato 2009 J. Choice Model. 2, 65-100. (doi:10.1016/S1755-5345(13)70005-8)) and drive the development of transportation systems. Current route-choice models that are used in transportation planning are based on the widely accepted assumption that people follow the minimum cost path (Wardrop 1952 Proc. Inst. Civ. Eng. 1, 325-362. (doi:10.1680/ipeds.1952.11362)), despite little empirical support. Fine-grained location traces collected by smart devices give us today an unprecedented opportunity to learn how citizens organize their travel plans into a set of routes, and how similar behaviour patterns emerge among distinct individual choices. Here we study 92 419 anonymized GPS trajectories describing the movement of personal cars over an 18-month period. We group user trips by origin-destination and we find that most drivers use a small number of routes for their routine journeys, and tend to have a preferred route for frequent trips. In contrast to the cost minimization assumption, we also find that a significant fraction of drivers' routes are not optimal. We present a spatial probability distribution that bounds the route selection space within an ellipse, having the origin and the destination as focal points, characterized by high eccentricity independent of the scale. While individual routing choices are not captured by path optimization, their spatial bounds are similar, even for trips performed by distinct individuals and at various scales. These basic discoveries can inform realistic route-choice models that are not based on optimization, having an impact on several applications, such as infrastructure planning, routing recommendation systems and new mobility solutions. © 2016 The Author(s).

  12. Path Diversity Improved Opportunistic Routing for Underwater Sensor Networks.

    Science.gov (United States)

    Bai, Weigang; Wang, Haiyan; He, Ke; Zhao, Ruiqin

    2018-04-23

    The packets carried along a pre-defined route in underwater sensor networks are very vulnerble. Node mobility or intermittent channel availability easily leads to unreachable routing. Opportunistic routing has been proven to be a promising paradigm to design routing protocols for underwater sensor networks. It takes advantage of the broadcast nature of the wireless medium to combat packet losses and selects potential paths on the fly. Finding an appropriate forwarding candidate set is a key issue in opportunistic routing. Many existing solutions ignore the impact of candidates location distribution on packet forwarding. In this paper, a path diversity improved candidate selection strategy is applied in opportunistic routing to improve packet forwarding efficiency. It not only maximizes the packet forwarding advancements but also takes the candidate’s location distribution into account. Based on this strategy, we propose two effective routing protocols: position improved candidates selection (PICS) and position random candidates selection (PRCS). PICS employs two-hop neighbor information to make routing decisions. PRCS only uses one-hop neighbor information. Simulation results show that both PICS and PRCS can significantly improve network performance when compared with the previous solutions, in terms of packet delivery ratio, average energy consumption and end-to-end delay.

  13. Path Diversity Improved Opportunistic Routing for Underwater Sensor Networks

    Directory of Open Access Journals (Sweden)

    Weigang Bai

    2018-04-01

    Full Text Available The packets carried along a pre-defined route in underwater sensor networks are very vulnerble. Node mobility or intermittent channel availability easily leads to unreachable routing. Opportunistic routing has been proven to be a promising paradigm to design routing protocols for underwater sensor networks. It takes advantage of the broadcast nature of the wireless medium to combat packet losses and selects potential paths on the fly. Finding an appropriate forwarding candidate set is a key issue in opportunistic routing. Many existing solutions ignore the impact of candidates location distribution on packet forwarding. In this paper, a path diversity improved candidate selection strategy is applied in opportunistic routing to improve packet forwarding efficiency. It not only maximizes the packet forwarding advancements but also takes the candidate’s location distribution into account. Based on this strategy, we propose two effective routing protocols: position improved candidates selection (PICS and position random candidates selection (PRCS. PICS employs two-hop neighbor information to make routing decisions. PRCS only uses one-hop neighbor information. Simulation results show that both PICS and PRCS can significantly improve network performance when compared with the previous solutions, in terms of packet delivery ratio, average energy consumption and end-to-end delay.

  14. Delay Tolerance in Underwater Wireless Communications: A Routing Perspective

    Directory of Open Access Journals (Sweden)

    Safdar Hussain Bouk

    2016-01-01

    Full Text Available Similar to terrestrial networks, underwater wireless networks (UWNs also aid several critical tasks including coastal surveillance, underwater pollution detection, and other maritime applications. Currently, once underwater sensor nodes are deployed at different levels of the sea, it is nearly impossible or very expensive to reconfigure the hardware, for example, battery. Taking this issue into account, considerable amount of research has been carried out to ensure minimum energy costs and reliable communication between underwater nodes and base stations. As a result, several different network protocols were proposed for UWN, including MAC, PHY, transport, and routing. Recently, a new paradigm was introduced claiming that the intermittent nature of acoustic channel and signal resulted in designing delay tolerant routing schemes for the UWN, known as an underwater delay tolerant network. In this paper, we provide a comprehensive survey of underwater routing protocols with emphasis on the limitations, challenges, and future open issues in the context of delay tolerant network routing.

  15. Multi-hop routing in wireless sensor networks an overview, taxonomy, and research challenges

    CERN Document Server

    Rani, Shalli

    2016-01-01

    This brief provides an overview of recent developments in multi-hop routing protocols for Wireless Sensor Networks (WSNs). It introduces the various classifications of routing protocols and lists the pros and cons of each category, going beyond the conceptual overview of routing classifications offered in other books. Recently many researchers have proposed numerous multi-hop routing protocols and thereby created a need for a book that provides its readers with an up-to-date road map of this research paradigm.   The authors present some of the most relevant results achieved by applying an algorithmic approach to the research on multi-hop routing protocols. The book covers measurements, experiences and lessons learned from the implementation of multi-hop communication prototypes. Furthermore, it describes future research challenges and as such serves as a useful guide for students and researchers alike.

  16. Routing and scheduling problems

    DEFF Research Database (Denmark)

    Reinhardt, Line Blander

    couple of decades. To deliver competitive service and price, transportation today needs to be cost effective. A company requiring for things to be shipped will aim at having the freight shipped as cheaply as possible while often satisfying certain time constraints. For the transportation company......, the effectiveness of the network is of importance aiming at satisfying as many costumer demands as possible at a low cost. Routing represent a path between locations such as an origin and destination for the object routed. Sometimes routing has a time dimension as well as the physical paths. This may...... set cost making the cost of the individual vehicle routes inter-dependant. Depending on the problem type, the size of the problems and time available for solving, different solution methods can be applicable. In this thesis both heuristic methods and several exact methods are investigated depending...

  17. Class network routing

    Science.gov (United States)

    Bhanot, Gyan [Princeton, NJ; Blumrich, Matthias A [Ridgefield, CT; Chen, Dong [Croton On Hudson, NY; Coteus, Paul W [Yorktown Heights, NY; Gara, Alan G [Mount Kisco, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Steinmacher-Burow, Burkhard D [Mount Kisco, NY; Takken, Todd E [Mount Kisco, NY; Vranas, Pavlos M [Bedford Hills, NY

    2009-09-08

    Class network routing is implemented in a network such as a computer network comprising a plurality of parallel compute processors at nodes thereof. Class network routing allows a compute processor to broadcast a message to a range (one or more) of other compute processors in the computer network, such as processors in a column or a row. Normally this type of operation requires a separate message to be sent to each processor. With class network routing pursuant to the invention, a single message is sufficient, which generally reduces the total number of messages in the network as well as the latency to do a broadcast. Class network routing is also applied to dense matrix inversion algorithms on distributed memory parallel supercomputers with hardware class function (multicast) capability. This is achieved by exploiting the fact that the communication patterns of dense matrix inversion can be served by hardware class functions, which results in faster execution times.

  18. Proxies for Anonymous Routing

    National Research Council Canada - National Science Library

    Reed, Michael G; Syverson, Paul F; Goldschlag, David M

    1996-01-01

    ...), and file transfers (FTP) have been implemented. Onion routing provides application independent, real-time, and bi-directional anonymous connections that are resistant to both eavesdropping and traffic analysis...

  19. Routes and Stations

    Data.gov (United States)

    Department of Homeland Security — he Routes_Stations table is composed of fixed rail transit systems within the Continental United States, Alaska, Hawaii, the District of Columbia, and Puerto Rico....

  20. Contention aware mobility prediction routing for intermittently connected mobile networks

    KAUST Repository

    Elwhishi, Ahmed; Ho, Pin-Han; Shihada, Basem

    2013-01-01

    This paper introduces a novel multi-copy routing protocol, called predict and forward (PF), for delay tolerant networks, which aims to explore the possibility of using mobile nodes as message carriers for end-to-end delivery of the messages. With PF, the message forwarding decision is made by manipulating the probability distribution of future inter-contact and contact durations based on the network status, including wireless link condition and nodal buffer availability. In particular, PF is based on the observations that the node mobility behavior is semi-deterministic and could be predicted once there is sufficient mobility history information. We implemented the proposed protocol and compared it with a number of existing encounter-based routing approaches in terms of delivery delay, delivery ratio, and the number of transmissions required for message delivery. The simulation results show that PF outperforms all the counterpart multi-copy encounter-based routing protocols considered in the study.

  1. Contention aware mobility prediction routing for intermittently connected mobile networks

    KAUST Repository

    Elwhishi, Ahmed

    2013-04-26

    This paper introduces a novel multi-copy routing protocol, called predict and forward (PF), for delay tolerant networks, which aims to explore the possibility of using mobile nodes as message carriers for end-to-end delivery of the messages. With PF, the message forwarding decision is made by manipulating the probability distribution of future inter-contact and contact durations based on the network status, including wireless link condition and nodal buffer availability. In particular, PF is based on the observations that the node mobility behavior is semi-deterministic and could be predicted once there is sufficient mobility history information. We implemented the proposed protocol and compared it with a number of existing encounter-based routing approaches in terms of delivery delay, delivery ratio, and the number of transmissions required for message delivery. The simulation results show that PF outperforms all the counterpart multi-copy encounter-based routing protocols considered in the study.

  2. Secure Multicast Routing Algorithm for Wireless Mesh Networks

    Directory of Open Access Journals (Sweden)

    Rakesh Matam

    2016-01-01

    Full Text Available Multicast is an indispensable communication technique in wireless mesh network (WMN. Many applications in WMN including multicast TV, audio and video conferencing, and multiplayer social gaming use multicast transmission. On the other hand, security in multicast transmissions is crucial, without which the network services are significantly disrupted. Existing secure routing protocols that address different active attacks are still vulnerable due to subtle nature of flaws in protocol design. Moreover, existing secure routing protocols assume that adversarial nodes cannot share an out-of-band communication channel which rules out the possibility of wormhole attack. In this paper, we propose SEMRAW (SEcure Multicast Routing Algorithm for Wireless mesh network that is resistant against all known active threats including wormhole attack. SEMRAW employs digital signatures to prevent a malicious node from gaining illegitimate access to the message contents. Security of SEMRAW is evaluated using the simulation paradigm approach.

  3. Bioremediation protocols

    National Research Council Canada - National Science Library

    Sheehan, David

    1997-01-01

    ..., .. . . . . .. ,. . . .. . . . . . . . .. . . . . .. . . .. . .. 3 2 Granular Nina Sludge Christiansen, Consortia lndra for Bioremediation, M. Mathrani, and Birgitte K. Ahring . 23 PART II PROTOCOLS...

  4. Routed planar networks

    Directory of Open Access Journals (Sweden)

    David J. Aldous

    2016-04-01

    Full Text Available Modeling a road network as a planar graph seems very natural. However, in studying continuum limits of such networks it is useful to take {\\em routes} rather than {\\em edges} as primitives. This article is intended to introduce the relevant (discrete setting notion of {\\em routed network} to graph theorists. We give a naive classification of all 71 topologically different such networks on 4 leaves, and pose a variety of challenging research questions.

  5. Enhanced Contact Graph Routing (ECGR) MACHETE Simulation Model

    Science.gov (United States)

    Segui, John S.; Jennings, Esther H.; Clare, Loren P.

    2013-01-01

    Contact Graph Routing (CGR) for Delay/Disruption Tolerant Networking (DTN) space-based networks makes use of the predictable nature of node contacts to make real-time routing decisions given unpredictable traffic patterns. The contact graph will have been disseminated to all nodes before the start of route computation. CGR was designed for space-based networking environments where future contact plans are known or are independently computable (e.g., using known orbital dynamics). For each data item (known as a bundle in DTN), a node independently performs route selection by examining possible paths to the destination. Route computation could conceivably run thousands of times a second, so computational load is important. This work refers to the simulation software model of Enhanced Contact Graph Routing (ECGR) for DTN Bundle Protocol in JPL's MACHETE simulation tool. The simulation model was used for performance analysis of CGR and led to several performance enhancements. The simulation model was used to demonstrate the improvements of ECGR over CGR as well as other routing methods in space network scenarios. ECGR moved to using earliest arrival time because it is a global monotonically increasing metric that guarantees the safety properties needed for the solution's correctness since route re-computation occurs at each node to accommodate unpredicted changes (e.g., traffic pattern, link quality). Furthermore, using earliest arrival time enabled the use of the standard Dijkstra algorithm for path selection. The Dijkstra algorithm for path selection has a well-known inexpensive computational cost. These enhancements have been integrated into the open source CGR implementation. The ECGR model is also useful for route metric experimentation and comparisons with other DTN routing protocols particularly when combined with MACHETE's space networking models and Delay Tolerant Link State Routing (DTLSR) model.

  6. Dynamic-Threshold-Limited Timed-Token (DTLTT) Protocol | Kalu ...

    African Journals Online (AJOL)

    An improved version of the Static-Threshold-Limited On-Demand Guaranteed Service Timed-Token (STOGSTT) Media Access Control (MAC) protocol for channel capacity allocation to the asynchronous trac in Multiservice Local Area Network (MLANs) was developed and analyzed. TLODGSTT protocol uses static value of ...

  7. DTN routing in body sensor networks with dynamic postural partitioning.

    Science.gov (United States)

    Quwaider, Muhannad; Biswas, Subir

    2010-11-01

    This paper presents novel store-and-forward packet routing algorithms for Wireless Body Area Networks ( WBAN ) with frequent postural partitioning. A prototype WBAN has been constructed for experimentally characterizing on-body topology disconnections in the presence of ultra short range radio links, unpredictable RF attenuation, and human postural mobility. On-body DTN routing protocols are then developed using a stochastic link cost formulation, capturing multi-scale topological localities in human postural movements. Performance of the proposed protocols are evaluated experimentally and via simulation, and are compared with a number of existing single-copy DTN routing protocols and an on-body packet flooding mechanism that serves as a performance benchmark with delay lower-bound. It is shown that via multi-scale modeling of the spatio-temporal locality of on-body link disconnection patterns, the proposed algorithms can provide better routing performance compared to a number of existing probabilistic, opportunistic, and utility-based DTN routing protocols in the literature.

  8. Study protocol for a prospective cohort study examining the predictive potential of dynamic symptom networks for the onset and progression of psychosis: the Mapping Individual Routes of Risk and Resilience (Mirorr) study.

    Science.gov (United States)

    Booij, Sanne H; Wichers, Marieke; de Jonge, Peter; Sytema, Sjoerd; van Os, Jim; Wunderink, Lex; Wigman, Johanna T W

    2018-01-21

    Our current ability to predict the course and outcome of early psychotic symptoms is limited, hampering timely treatment. To improve our understanding of the development of psychosis, a different approach to psychopathology may be productive. We propose to reconceptualise psychopathology from a network perspective, according to which symptoms act as a dynamic, interconnected system, impacting on each other over time and across diagnostic boundaries to form symptom networks. Adopting this network approach, the Mapping Individual Routes of Risk and Resilience study aims to determine whether characteristics of symptom networks can predict illness course and outcome of early psychotic symptoms. The sample consists of n=100 participants aged 18-35 years, divided into four subgroups (n=4×25) with increasing levels of severity of psychopathology, representing successive stages of clinical progression. Individuals representing the initial stage have a relatively low expression of psychotic experiences (general population), whereas individuals representing the end stage are help seeking and display a psychometric expression of psychosis, putting them at ultra-high risk for transition to psychotic disorder. At baseline and 1-year follow-up, participants report their symptoms, affective states and experiences for three consecutive months in short, daily questionnaires on their smartphone, which will be used to map individual networks. Network parameters, including the strength and directionality of symptom connections and centrality indices, will be estimated and associated to individual differences in and within-individual progression through stages of clinical severity and functioning over the next 3 years. The study has been approved by the local medical ethical committee (ABR no. NL52974.042.15). The results of the study will be published in (inter)national peer-reviewed journals, presented at research, clinical and general public conferences. The results will assist

  9. Transmission Scheduling and Routing Algorithms for Delay Tolerant Networks

    Science.gov (United States)

    Dudukovich, Rachel; Raible, Daniel E.

    2016-01-01

    The challenges of data processing, transmission scheduling and routing within a space network present a multi-criteria optimization problem. Long delays, intermittent connectivity, asymmetric data rates and potentially high error rates make traditional networking approaches unsuitable. The delay tolerant networking architecture and protocols attempt to mitigate many of these issues, yet transmission scheduling is largely manually configured and routes are determined by a static contact routing graph. A high level of variability exists among the requirements and environmental characteristics of different missions, some of which may allow for the use of more opportunistic routing methods. In all cases, resource allocation and constraints must be balanced with the optimization of data throughput and quality of service. Much work has been done researching routing techniques for terrestrial-based challenged networks in an attempt to optimize contact opportunities and resource usage. This paper examines several popular methods to determine their potential applicability to space networks.

  10. Routing in Mobile Wireless Sensor Networks: A Leader-Based Approach.

    Science.gov (United States)

    Burgos, Unai; Amozarrain, Ugaitz; Gómez-Calzado, Carlos; Lafuente, Alberto

    2017-07-07

    This paper presents a leader-based approach to routing in Mobile Wireless Sensor Networks (MWSN). Using local information from neighbour nodes, a leader election mechanism maintains a spanning tree in order to provide the necessary adaptations for efficient routing upon the connectivity changes resulting from the mobility of sensors or sink nodes. We present two protocols following the leader election approach, which have been implemented using Castalia and OMNeT++. The protocols have been evaluated, besides other reference MWSN routing protocols, to analyse the impact of network size and node velocity on performance, which has demonstrated the validity of our approach.

  11. Neighboring and Connectivity-Aware Routing in VANETs

    Directory of Open Access Journals (Sweden)

    Huma Ghafoor

    2014-01-01

    Full Text Available A novel position-based routing protocol anchor-based connectivity-aware routing (ACAR for vehicular ad hoc networks (VANETs is proposed in this paper to ensure connectivity of routes with more successfully delivered packets. Both buses and cars are considered as vehicular nodes running in both clockwise and anticlockwise directions in a city scenario. Both directions are taken into account for faster communication. ACAR is a hybrid protocol, using both the greedy forwarding approach and the store-carry-and-forward approach to minimize the packet drop rate on the basis of certain assumptions. Our solution to situations that occur when the network is sparse and when any (source or intermediate node has left its initial position makes this protocol different from those existing in the literature. We consider only vehicle-to-vehicle (V2V communication in which both the source and destination nodes are moving vehicles. Also, no road-side units are considered. Finally, we compare our protocol with A-STAR (a plausible connectivity-aware routing protocol for city environments, and simulation results in NS-2 show improvement in the number of packets delivered to the destination using fewer hops. Also, we show that ACAR has more successfully-delivered long-distance packets with reasonable packet delay than A-STAR.

  12. ARBR: Adaptive reinforcement-based routing for DTN

    KAUST Repository

    Elwhishi, Ahmed

    2010-10-01

    This paper introduces a novel routing protocol in Delay Tolerant Networks (DTNs), aiming to solve the online distributed routing problem. By manipulating a collaborative reinforcement learning technique, a group of nodes can cooperate with each other and make a forwarding decision for the stored messages based on a cost function at each contact with another node. The proposed protocol is characterized by not only considering the contact time statistics under a novel contact model, but also looks into the feedback on user behavior and network conditions, such as congestion and buffer occupancy sampled during each previous contact with any other node. Therefore, the proposed protocol can achieve high efficiency via an adaptive and intelligent routing mechanism according to network conditions. Extensive simulation is conducted to verify the proposed protocol, where a comparison is made with a number of existing encounter-based routing protocols in term of the number of transmissions of each message, message delivery delay, and delivery ratio. The results of the simulation demonstrate the effectiveness of the proposed technique.

  13. Access control infrastructure for on-demand provisioned virtualised infrastructure services

    NARCIS (Netherlands)

    Demchenko, Y.; Ngo, C.; de Laat, C.; Smari, W.W.; Fox, G.C.

    2011-01-01

    Cloud technologies are emerging as a new way of provisioning virtualised computing and infrastructure services on-demand for collaborative projects and groups. Security in provisioning virtual infrastructure services should address two general aspects: supporting secure operation of the provisioning

  14. On-Demand Dark Soliton Train Manipulation in a Spinor Polariton Condensate

    KAUST Repository

    Pinsker, F.; Flayac, H.

    2014-01-01

    or electrically to provide a stable and efficient output signal modulation. Taking the polarization of the condensate into account, we elucidate the possibility of forming on-demand half-soliton trains. © 2014 American Physical Society.

  15. Routing in IPv6 over Low-Power Wireless Personal Area Networks (6LoWPAN: A Survey

    Directory of Open Access Journals (Sweden)

    Vinay Kumar

    2012-01-01

    Full Text Available 6LoWPANs (IPv6-based Low-Power Personal Area Networks are formulated by devices that are compatible with the IEEE 802.15.4 standard. To moderate the effects of network mobility, the Internet Protocol (IP does not calculate routes; it is left to a routing protocol, which maintains routing tables in the routers. 6LowPAN uses an adaptation layer between the network (IPv6 and data link layer (IEEE802.15.4 MAC to fragment and reassemble IPv6 packets. The routing in 6LoWPAN is primarily divided on the basis of routing decision taken on adaptation or network layer. The objective of this paper is to present a state-of-the-art survey of existing routing protocols: LOAD, M-LOAD, DYMO-Low, Hi-Low, Extended Hi-Low, and S-AODV. These routing protocols have compared on the basis of different metric like energy consumption, memory uses, mobility, scalability, routing delay, an RERR message, a Hello message, and local repair. We have also presented the taxonomy of routing requirement; parameter for evaluating routing algorithm, and it was found that the routing protocol has its own advantages depending upon the application where it is used.

  16. Routine versus on demand removal of the syndesmotic screw; a protocol for an international randomised controlled trial (RODEO-trial)

    NARCIS (Netherlands)

    Dingemans, S. A.; Birnie, M. F. N.; Sanders, F. R. K.; van den Bekerom, M. P. J.; Backes, M.; van Beeck, E.; Bloemers, F. W.; van Dijkman, B.; Flikweert, E.; Haverkamp, D.; Holtslag, H. R.; Hoogendoorn, J. M.; Joosse, P.; Parkkinen, M.; Roukema, G.; Sosef, N.; Twigt, B. A.; van Veen, R. N.; van der Veen, A. H.; Vermeulen, J.; Winkelhagen, J.; van der Zwaard, B. C.; van Dieren, S.; Goslings, J. C.; Schepers, T.

    2018-01-01

    Background: Syndesmotic injuries are common and their incidence is rising. In case of surgical fixation of the syndesmosis a metal syndesmotic screw is used most often. It is however unclear whether this screw needs to be removed routinely after the syndesmosis has healed. Traditionally the screw is

  17. Routine versus on demand removal of the syndesmotic screw; A protocol for an international randomised controlled trial (RODEO-trial)

    NARCIS (Netherlands)

    S.A. Dingemans (Siem); Birnie, M.F.N. (M. F.N.); Sanders, F.R.K. (F. R.K.); M.P.J. van den Bekerom (Michel); Backes, M. (M.); E.F. van Beeck (Ed); F.W. Bloemers (Frank); B.A. van Dijkman (Bart); E.R. Flikweert (Elvira); D.J. Haverkamp; H.R. Holtslag (Herman); Hoogendoorn, J.M. (J. M.); P. Joosse (Pieter); Parkkinen, M. (M.); G.R. Roukema (Gert); N.L. Sosef (Nico L.); B. Twigt (Bas); R.N. van Veen (Ruben); Van Der Veen, A.H. (A. H.); Vermeulen, J. (J.); Winkelhagen, J. (J.); Van Der Zwaard, B.C. (B. C.); S. Van Dieren (Susan); J.C. Goslings (Carel); T. Schepers (Tim)

    2018-01-01

    textabstractBackground: Syndesmotic injuries are common and their incidence is rising. In case of surgical fixation of the syndesmosis a metal syndesmotic screw is used most often. It is however unclear whether this screw needs to be removed routinely after the syndesmosis has healed. Traditionally

  18. Technology Transfer Opportunities: On-Demand Printing in Support of National Geospatial Data

    Science.gov (United States)

    ,

    1997-01-01

    The U.S. Geological Survey (USGS) and the 3M Company of St. Paul, Minnesota, have entered into a cooperative research and development agreement (CRADA) to investigate maps-on-demand technology to support the production of USGS mapping products. The CRADA will potentially help the USGS to develop on-demand alternatives to lithographic maps and help 3M to develop a series of commercial instant map-printing systems.

  19. Development of a New Web Portal for the Database on Demand Service

    CERN Document Server

    Altinigne, Can Yilmaz

    2017-01-01

    The Database on Demand service allows members of CERN communities to provision and manage database instances of different flavours (MySQL, Oracle, PostgreSQL and InfluxDB). Users can create and edit these instances using the web interface of DB On Demand. This web front end is currently on Java technologies and the ZK web framework, for which is generally difficult to find experienced developers and which has gotten to lack behind more modern web stacks in capabilities and usability.

  20. Window-Based Popularity Caching for IPTV On-Demand Services

    OpenAIRE

    Hsuan Chiu; Chi-He Chang; Chao-Wei Tseng; Chi-Shi Liu

    2011-01-01

    In recent years, many telecommunication companies have regarded IP network as a new delivery platform for providing TV services because IP network is equipped with two-way and high-speed communication abilities which are appropriate to provide on-demand services and linear TV programs. However, in this IPTV system, the requests of VOD (video on demand) are usually aggregated in a short period intensively and user preferences are fluctuated dynamically. Moreover, the VOD content is updated fre...

  1. Tailoring single-photon and multiphoton probabilities of a single-photon on-demand source

    International Nuclear Information System (INIS)

    Migdall, A.L.; Branning, D.; Castelletto, S.

    2002-01-01

    As typically implemented, single-photon sources cannot be made to produce single photons with high probability, while simultaneously suppressing the probability of yielding two or more photons. Because of this, single-photon sources cannot really produce single photons on demand. We describe a multiplexed system that allows the probabilities of producing one and more photons to be adjusted independently, enabling a much better approximation of a source of single photons on demand

  2. Efficacy of On-Demand Therapy Using 20-mg Vonoprazan for Mild Reflux Esophagitis.

    Science.gov (United States)

    Umezawa, Mariko; Kawami, Noriyuki; Hoshino, Shintaro; Hoshikawa, Yoshimasa; Koizumi, Eriko; Takenouchi, Nana; Hanada, Yuriko; Kaise, Mitsuru; Iwakiri, Katsuhiko

    2018-01-01

    The study aimed to evaluate the efficacy of on-demand therapy using 20-mg vonoprazan for mild reflux esophagitis (RE). On-demand therapy by taking one 20-mg tablet of vonoprazan only when reflux symptoms occurred was performed for 24 weeks using 30 patients with mild RE who were receiving maintenance therapy with proton pomp inhibitors (PPIs). The presence or absence of RE, degree of overall satisfaction with the treatment, score of symptoms, and fasting gastrin level before breakfast were examined before and after on-demand therapy. The number of tablets taken during the 24-week period was also noted. One of the 30 patients dropped out of on-demand therapy 1 week after its initiation. Remission was maintained in 25 (86.2%) of the 29 patients (all 10 [100%] Los Angeles classification grade A patients and 15 (78.9%) of the 19 grade B patients). However, 4 grade B patients exhibited grade B relapse. There were no differences in the degree of overall satisfaction, score of symptoms or the gastrin level between PPI and on-demand therapies. The number of vonoprazan tablets taken during the observation period was 33 tablets (median)/24 weeks. On-demand therapy using 20-mg vonoprazan tablets is an effective alternative maintenance therapy for mild RE. © 2018 S. Karger AG, Basel.

  3. Collective network routing

    Science.gov (United States)

    Hoenicke, Dirk

    2014-12-02

    Disclosed are a unified method and apparatus to classify, route, and process injected data packets into a network so as to belong to a plurality of logical networks, each implementing a specific flow of data on top of a common physical network. The method allows to locally identify collectives of packets for local processing, such as the computation of the sum, difference, maximum, minimum, or other logical operations among the identified packet collective. Packets are injected together with a class-attribute and an opcode attribute. Network routers, employing the described method, use the packet attributes to look-up the class-specific route information from a local route table, which contains the local incoming and outgoing directions as part of the specifically implemented global data flow of the particular virtual network.

  4. Optimizing well intervention routes

    Energy Technology Data Exchange (ETDEWEB)

    Paiva, Ronaldo O. [PETROBRAS S.A., Vitoria, ES (Brazil); Schiozer, Denis J.; Bordalo, Sergio N. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Centro de Estudo do Petroleo (CEPETRO)]. E-mail: denis@dep.fem.unicamp.br; bordalo@dep.fem.unicamp.br

    2000-07-01

    This work presents a method for optimizing the itinerary of work over rigs, i.e., the search for the route of minimum total cost, and demonstrates the importance of the dynamics of reservoir behaviour. The total cost of a route includes the rig expenses (transport, assembly and operation), which are functions of time and distances, plus the losses of revenue in wells waiting for the rig, which are also dependent of time. A reservoir simulator is used to evaluate the monetary influence of the well shutdown on the present value of the production curve. Finally, search algorithms are employed to determine the route of minimal cost. The Simulated Annealing algorithm was also successful in optimizing the distribution of a list of wells among different work over rigs. The rational approach presented here is recommended for management teams as a standard procedure to define the priority of wells scheduled for work over. (author)

  5. ROUTING DEMAND CHANGES TO USERS ON THE WM LATERAL CANAL WITH SACMAN

    Science.gov (United States)

    Most canals have either long travel times or insufficient in-canal storage to operate on-demand. Thus, most flow changes must be routed through the canal. Volume compensation has been proposed as a method for easily applying feedforward control to irrigation canals. SacMan (Software for Automated Ca...

  6. SET-Routes programme

    CERN Multimedia

    Marietta Schupp, EMBL Photolab

    2008-01-01

    Dr Sabine Hentze, specialist in human genetics, giving an Insight Lecture entitled "Human Genetics – Diagnostics, Indications and Ethical Issues" on 23 September 2008 at EMBL Heidelberg. Activities in a achool in Budapest during a visit of Angela Bekesi, Ambassadors for the SET-Routes programme.

  7. Design alternatives for wavelength routing networks

    Science.gov (United States)

    Miliotis, K.; Papadimitriou, G. I.; Pomportsis, A. S.

    2003-03-01

    This paper attempts to provide a high level overview of many of the technologies employed in optical networks with a focus on wavelength-routing networks. Optical networks involve a number of technologies from the physics of light through protocols and networks architectures. In fact there is so much technology and know-how that most people involved with optical networks only have a full understanding of the narrow area they deal with. We start first examining the principles that govern light and its use as a wave guide, and then turn our focus to the various components that constitute an optical network and conclude with the description of all optical networks and wavelength-routed networks in greater detail.

  8. An Emergency-Adaptive Routing Scheme for Wireless Sensor Networks for Building Fire Hazard Monitoring

    Directory of Open Access Journals (Sweden)

    Guilin Zheng

    2011-03-01

    Full Text Available Fire hazard monitoring and evacuation for building environments is a novel application area for the deployment of wireless sensor networks. In this context, adaptive routing is essential in order to ensure safe and timely data delivery in building evacuation and fire fighting resource applications. Existing routing mechanisms for wireless sensor networks are not well suited for building fires, especially as they do not consider critical and dynamic network scenarios. In this paper, an emergency-adaptive, real-time and robust routing protocol is presented for emergency situations such as building fire hazard applications. The protocol adapts to handle dynamic emergency scenarios and works well with the routing hole problem. Theoretical analysis and simulation results indicate that our protocol provides a real-time routing mechanism that is well suited for dynamic emergency scenarios in building fires when compared with other related work.

  9. Key on demand (KoD) for software-defined optical networks secured by quantum key distribution (QKD).

    Science.gov (United States)

    Cao, Yuan; Zhao, Yongli; Colman-Meixner, Carlos; Yu, Xiaosong; Zhang, Jie

    2017-10-30

    Software-defined optical networking (SDON) will become the next generation optical network architecture. However, the optical layer and control layer of SDON are vulnerable to cyberattacks. While, data encryption is an effective method to minimize the negative effects of cyberattacks, secure key interchange is its major challenge which can be addressed by the quantum key distribution (QKD) technique. Hence, in this paper we discuss the integration of QKD with WDM optical networks to secure the SDON architecture by introducing a novel key on demand (KoD) scheme which is enabled by a novel routing, wavelength and key assignment (RWKA) algorithm. The QKD over SDON with KoD model follows two steps to provide security: i) quantum key pools (QKPs) construction for securing the control channels (CChs) and data channels (DChs); ii) the KoD scheme uses RWKA algorithm to allocate and update secret keys for different security requirements. To test our model, we define a security probability index which measures the security gain in CChs and DChs. Simulation results indicate that the security performance of CChs and DChs can be enhanced by provisioning sufficient secret keys in QKPs and performing key-updating considering potential cyberattacks. Also, KoD is beneficial to achieve a positive balance between security requirements and key resource usage.

  10. The Prohibitive Link between Position-based Routing and Planarity

    Directory of Open Access Journals (Sweden)

    David Cairns

    2013-12-01

    Full Text Available Position-based routing is touted as an ideal routing strategy for resource-constrained wireless networks. One persistent barrier to adoption is due to its recovery phase, where messages are forwarded according to leftor right-hand rule (LHR. This is often referred to as face-routing. In this paper we investigate the limits of LHR with respect to planarity.We show that the gap between non-planarity and successful delivery is a single link within a single configuration. Our work begins with an analysis to enumerate all node configurations that cause intersections in the unit-disc graph. We find that left-hand rule is able to recover from all but a single case, the ‘umbrella’ configuration so named for its appearance. We use this information to propose the Prohibitive Link Detection Protocol (PLDP that can guarantee delivery over non-planar graphs using standard face-routing techniques. As the name implies, the protocol detects and circumvents the ‘bad’ links that hamper LHR. The goal of this work is to maintain routing guarantees while disturbing the network graph as little as possible. In doing so, a new starting point emerges from which to build rich distributed protocols in the spirit of CLDP and GDSTR.

  11. Privacy-Preserving Interdomain Routing at Internet Scale

    Directory of Open Access Journals (Sweden)

    Asharov Gilad

    2017-07-01

    Full Text Available The Border Gateway Protocol (BGP computes routes between the organizational networks that make up today’s Internet. Unfortunately, BGP suffers from deficiencies, including slow convergence, security problems, a lack of innovation, and the leakage of sensitive information about domains’ routing preferences. To overcome some of these problems, we revisit the idea of centralizing and using secure multi-party computation (MPC for interdomain routing which was proposed by Gupta et al. (ACM HotNets’12. We implement two algorithms for interdomain routing with state-of-the-art MPC protocols. On an empirically derived dataset that approximates the topology of today’s Internet (55 809 nodes, our protocols take as little as 6 s of topology-independent precomputation and only 3 s of online time. We show, moreover, that when our MPC approach is applied at country/region-level scale, runtimes can be as low as 0.17 s online time and 0.20 s pre-computation time. Our results motivate the MPC approach for interdomain routing and furthermore demonstrate that current MPC techniques are capable of efficiently tackling real-world problems at a large scale.

  12. Distributed Fault-Tolerant Quality Of Service Routing in Hybrid Directional Wireless Networks

    National Research Council Canada - National Science Library

    Llewellyn, II, Larry C

    2007-01-01

    This thesis presents a distributed fault-tolerant routing protocol (EFDCB) for QoS supporting hybrid mobile ad hoc networks with the aim of mitigating QoS disruption time when network failures occur...

  13. Trust-Based Route Selection in Dynamic Source Routin

    DEFF Research Database (Denmark)

    Jensen, Christian D.; Connell, Paul O

    2006-01-01

    in the mobile wireless network. However, blindly trusting all other nodes to respect the routing protocol exposes the local node to a wide variety of vulnerabilities. Traditional security mechanisms rely on either the authenticated identity of the requesting principal or some form of credentials that authorise...

  14. A novel insight into beaconless geo-routing

    KAUST Repository

    Bader, Ahmed

    2012-12-01

    Beaconless geo-routing protocols have been traditionally analyzed assuming equal communication ranges for the data and control packets. This is not true in reality, since the communication range is in practice function of the packet length. As a consequence, a substantial discrepancy may exist between analytical and empirical results offered in beaconless geo-routing literature. Furthermore, performance of beaconless geo-routing protocols has typically considered using single-hop metrics only. End-to-end performance is considered in literature only occasionally and mainly in terms of simulation only. In this paper, we re-examine this class of protocols. We first incorporate practical packet detection models in order to capture the dependency of the communication range on the packet\\'s length. We then develop a detailed analytical framework for the end-to-end delay and energy performance of beaconless geo-routing protocols. Finally, we present two different application scenarios and study various tradeoffs in light of the framework developed. © 2012 IEEE.

  15. Deflection routing scheme for GMPLS-based OBS networks

    DEFF Research Database (Denmark)

    Eid, Arafat; Mahmood, Waqar; Alomar, Anwar

    2010-01-01

    Integrating the Generalized Multi-Protocol Label Switching (GMPLS) framework into an Optical Burst Switching (OBS) Control Plane is a promising solution to alleviating most of OBS performance and design issues. However, implementing the already proposed OBS deflection routing schemes is not appli...

  16. Contention Aware Routing for Intermittently Connected Mobile Networks

    KAUST Repository

    Elwhishi, Ahmed; Ho, Pin Han; Naik, Sagar; Shihada, Basem

    2011-01-01

    This paper introduces a novel multi-copy routing protocol, called Self Adaptive Utility-based Routing Protocol (SAURP), for Delay Tolerant Networks (DTNs) that are possibly composed of a vast number of miniature devices such as smart phones, hand-held devices, and sensors mounted in fixed or mobile objects. SAURP aims to explore the possibility of taking mobile nodes as message carriers in order for end-to-end delivery of the messages. The best carrier for a message is determined by the prediction result using a novel contact model, where the network status, including wireless link condition and nodal buffer availability, are jointly considered. The paper argues and proves that the nodal movement and the predicted collocation with the message recipient can serve as meaningful information to achieve an intelligent message forwarding decision at each node. The proposed protocol has been implemented and compared with a number of existing encounter-based routing approaches in terms of delivery delay, and the number of transmissions required for message delivery. The simulation results show that the proposed SAURP outperforms all the counterpart multi-copy encounter-based routing protocols considered in the study.

  17. Contention Aware Routing for Intermittently Connected Mobile Networks

    KAUST Repository

    Elwhishi, Ahmed

    2011-08-21

    This paper introduces a novel multi-copy routing protocol, called Self Adaptive Utility-based Routing Protocol (SAURP), for Delay Tolerant Networks (DTNs) that are possibly composed of a vast number of miniature devices such as smart phones, hand-held devices, and sensors mounted in fixed or mobile objects. SAURP aims to explore the possibility of taking mobile nodes as message carriers in order for end-to-end delivery of the messages. The best carrier for a message is determined by the prediction result using a novel contact model, where the network status, including wireless link condition and nodal buffer availability, are jointly considered. The paper argues and proves that the nodal movement and the predicted collocation with the message recipient can serve as meaningful information to achieve an intelligent message forwarding decision at each node. The proposed protocol has been implemented and compared with a number of existing encounter-based routing approaches in terms of delivery delay, and the number of transmissions required for message delivery. The simulation results show that the proposed SAURP outperforms all the counterpart multi-copy encounter-based routing protocols considered in the study.

  18. DRO: domain-based route optimization scheme for nested mobile networks

    Directory of Open Access Journals (Sweden)

    Chuang Ming-Chin

    2011-01-01

    Full Text Available Abstract The network mobility (NEMO basic support protocol is designed to support NEMO management, and to ensure communication continuity between nodes in mobile networks. However, in nested mobile networks, NEMO suffers from the pinball routing problem, which results in long packet transmission delays. To solve the problem, we propose a domain-based route optimization (DRO scheme that incorporates a domain-based network architecture and ad hoc routing protocols for route optimization. DRO also improves the intra-domain handoff performance, reduces the convergence time during route optimization, and avoids the out-of-sequence packet problem. A detailed performance analysis and simulations were conducted to evaluate the scheme. The results demonstrate that DRO outperforms existing mechanisms in terms of packet transmission delay (i.e., better route-optimization, intra-domain handoff latency, convergence time, and packet tunneling overhead.

  19. Energy Efficient Link Aware Routing with Power Control in Wireless Ad Hoc Networks.

    Science.gov (United States)

    Katiravan, Jeevaa; Sylvia, D; Rao, D Srinivasa

    2015-01-01

    In wireless ad hoc networks, the traditional routing protocols make the route selection based on minimum distance between the nodes and the minimum number of hop counts. Most of the routing decisions do not consider the condition of the network such as link quality and residual energy of the nodes. Also, when a link failure occurs, a route discovery mechanism is initiated which incurs high routing overhead. If the broadcast nature and the spatial diversity of the wireless communication are utilized efficiently it becomes possible to achieve improvement in the performance of the wireless networks. In contrast to the traditional routing scheme which makes use of a predetermined route for packet transmission, such an opportunistic routing scheme defines a predefined forwarding candidate list formed by using single network metrics. In this paper, a protocol is proposed which uses multiple metrics such as residual energy and link quality for route selection and also includes a monitoring mechanism which initiates a route discovery for a poor link, thereby reducing the overhead involved and improving the throughput of the network while maintaining network connectivity. Power control is also implemented not only to save energy but also to improve the network performance. Using simulations, we show the performance improvement attained in the network in terms of packet delivery ratio, routing overhead, and residual energy of the network.

  20. Energy Efficient Link Aware Routing with Power Control in Wireless Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Jeevaa Katiravan

    2015-01-01

    Full Text Available In wireless ad hoc networks, the traditional routing protocols make the route selection based on minimum distance between the nodes and the minimum number of hop counts. Most of the routing decisions do not consider the condition of the network such as link quality and residual energy of the nodes. Also, when a link failure occurs, a route discovery mechanism is initiated which incurs high routing overhead. If the broadcast nature and the spatial diversity of the wireless communication are utilized efficiently it becomes possible to achieve improvement in the performance of the wireless networks. In contrast to the traditional routing scheme which makes use of a predetermined route for packet transmission, such an opportunistic routing scheme defines a predefined forwarding candidate list formed by using single network metrics. In this paper, a protocol is proposed which uses multiple metrics such as residual energy and link quality for route selection and also includes a monitoring mechanism which initiates a route discovery for a poor link, thereby reducing the overhead involved and improving the throughput of the network while maintaining network connectivity. Power control is also implemented not only to save energy but also to improve the network performance. Using simulations, we show the performance improvement attained in the network in terms of packet delivery ratio, routing overhead, and residual energy of the network.

  1. Provisioning of adaptability to variable topologies for routing schemes in MANETs

    DEFF Research Database (Denmark)

    Jiang, Shengming; Liu, Yaoda; Jiang, Yuming

    2004-01-01

    .g., low, medium, and high mobility) have been proposed in the,literature. However, since a mobile node should not be limited to operate in a particular MANET assumed by-a routing scheme, an important issue is how to enable, a mobile node to achieve routing performance as high as possible when it roams...... in the dynamic source routing protocol to provide the adaptability to variable topologies caused by mobility through computer simulation in NS-2....

  2. Modeling and Performance Analysis of Route-Over and Mesh-Under Routing Schemes in 6LoWPAN under Error-Prone Channel Condition

    Directory of Open Access Journals (Sweden)

    Tsung-Han Lee

    2013-01-01

    Full Text Available 6LoWPAN technology has attracted extensive attention recently. It is because 6LoWPAN is one of Internet of Things standard and it adapts to IPv6 protocol stack over low-rate wireless personal area network, such as IEEE 802.15.4. One view is that IP architecture is not suitable for low-rate wireless personal area network. It is a challenge to implement the IPv6 protocol stack into IEEE 802.15.4 devices due to that the size of IPv6 packet is much larger than the maximum packet size of IEEE 802.15.4 in data link layer. In order to solve this problem, 6LoWPAN provides header compression to reduce the transmission overhead for IP packets. In addition, two selected routing schemes, mesh-under and route-over routing schemes, are also proposed in 6LoWPAN to forward IP fragmentations under IEEE 802.15.4 radio link. The distinction is based on which layer of the 6LoWPAN protocol stack is in charge of routing decisions. In route-over routing scheme, the routing distinction is taken at the network layer and, in mesh-under, is taken by the adaptation layer. Thus, the goal of this research is to understand the performance of two routing schemes in 6LoWPAN under error-prone channel condition.

  3. British Dance: Black Routes

    OpenAIRE

    Adair, C.; Burt, Ramsay, 1953-

    2016-01-01

    British Dance: Black Routes re-examines the distinctive contributions made to British dance by dancers who are Black. Covering the period 1946 to the present, it presents a radical re-reading of dancers and their companies, placing their achievements within a broader historical, cultural and artistic context. The result of a two year research project, British Dance and the African Diaspora, led by editors Christy Adair and Ramsay Burt, the collection looks at artists working with contempor...

  4. Analysis of pervasive mobile ad hoc routing protocols

    NARCIS (Netherlands)

    Qadri, N.N.; Liotta, A.; Hassanien, A.E.; Abawajy, J.H.; Abraham, A.; Hagras, H.

    2009-01-01

    Pervasive computing (also referred to as ubiquitous computing or ambient intelligence) aims to create environments where computers are invisibly and seamlessly integrated and connected into our everyday environment. Pervasive computing and intelligent multimedia technologies are becoming

  5. Performance Evaluation of a Routing Protocol in Wireless Sensor Network

    National Research Council Canada - National Science Library

    Cheng Kiat Amos, Teo

    2005-01-01

    ... and have topologies engineered. As such, recent research into wireless sensor networks has attracted great interest due to its diversity of applications, ranging in areas such as home, health, environmental and military applications...

  6. ING: INDOOR ROUTING PROTOCOL FOR GREEN HOME NETWORKS

    OpenAIRE

    Kaouthar Sethom; Nozha Al- Ibrahimi; Guy Pujolle

    2011-01-01

    Because of all the innovations in computer communications and digital consumer device technologies,people have had great interest in researching home networking systems. The home is evolving rapidlyinto a smart Mesh networked environment.Moreover, the energy consumption of wireless devices and networks gradually increases to represent asignificant portion of the operational cost, naturally also causing increased equivalent carbonemissions to the environment. Therefore, reducing the energy con...

  7. Reliable Internet Routing

    Science.gov (United States)

    2011-09-01

    global coordination. IEEE/ACM Trans. Netw., 9(6):681–692, 2001. [39] S. Goldberg, D. Xiao, E. Tromer, B. Barak , and J. Rexford. Path-quality monitoring...RFC 4271). [81] Y. Rekhter, T. Li, and S. Hares. A border gateway protocol 4 (BGP-4), 2006. IETF RFC 4271. [82] E. Rosen , A. Viswanathan, and R. Callon

  8. On-demand virtual optical network access using 100 Gb/s Ethernet.

    Science.gov (United States)

    Ishida, Osamu; Takamichi, Toru; Arai, Sachine; Kawate, Ryusuke; Toyoda, Hidehiro; Morita, Itsuro; Araki, Soichiro; Ichikawa, Toshiyuki; Hoshida, Takeshi; Murai, Hitoshi

    2011-12-12

    Our Terabit LAN initiatives attempt to enhance the scalability and utilization of lambda resources. This paper describes bandwidth-on-demand virtualized 100GE access to WDM networks on a field fiber test-bed using multi-domain optical-path provisioning. © 2011 Optical Society of America

  9. Optimization-based feedforward control for a drop-on-demand inkjet printer

    NARCIS (Netherlands)

    Khalate, A.; Bombois, X.; Babuska, R.; Wijshoff, H.M.A.; Waarsing, R.

    2010-01-01

    The printing quality delivered by a Drop-on-Demand (DoD) inkjet printhead is limited due to operational issues such as residual oscillations in the ink channel and the cross-talk between the ink channels. The maximal jetting frequency of a DoD inkjet printhead can be increased by quickly damping the

  10. Just add water: reproducible singly dispersed silver nanoparticle suspensions on-demand

    International Nuclear Information System (INIS)

    MacCuspie, Robert I.; Allen, Andrew J.; Martin, Matthew N.; Hackley, Vincent A.

    2013-01-01

    Silver nanoparticles (AgNPs) are of interest due to their antimicrobial attributes, which are derived from their inherent redox instability and subsequent release of silver ions. At the same time, this instability is a substantial challenge for achieving stable long-term storage for on-demand use of AgNPs. In this study, we describe and validate a “just add water” approach for achieving suspensions of principally singly dispersed AgNPs. By lyophilizing (freeze drying) the formulated AgNPs into a solid powder, or cake, water is removed thereby eliminating solution-based chemical changes. Storing under inert gas further reduces surface reactions such as oxidation. An example of how to optimize a lyophilization formulation is presented, as well as example formulations for three AgNP core sizes. This “just add water” approach enables ease of use for the researcher desiring on-demand singly dispersed AgNP suspensions from a single master batch. Implementation of this methodology will enable studies to be performed over long periods of time and across different laboratories using particles that are identical chemically and physically and available on-demand. In addition, the approach of freeze drying and on-demand reconstitution by adding water has enabled the development of AgNP reference materials with the required shelf-life stability, one of the principal objectives of this research

  11. 26 CFR 1.453-3 - Purchaser evidences of indebtedness payable on demand or readily tradable.

    Science.gov (United States)

    2010-04-01

    ... obligation (determined by taking into account all relevant factors, including proper discount to reflect the... demand or readily tradable. 1.453-3 Section 1.453-3 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Income Included § 1.453-3 Purchaser evidences of indebtedness payable on demand or readily tradable. (a...

  12. Scheduling jobs in the cloud using on-demand and reserved instances

    NARCIS (Netherlands)

    Shen, S.; Deng, K.; Iosup, A.; Epema, D.H.J.; Wolf, F.; Mohr, B.; Mey, an D.

    2013-01-01

    Deploying applications in leased cloud infrastructure is increasingly considered by a variety of business and service integrators. However, the challenge of selecting the leasing strategy — larger or faster instances? on-demand or reserved instances? etc.— and to configure the leasing strategy with

  13. Impact-driven ejection of micro metal droplets on-demand

    NARCIS (Netherlands)

    Luo, Jun; Qi, Lehua; Tao, Yuan; Ma, Qian; Visser, C.W.

    2016-01-01

    On-demand metal droplet deposition will be a cornerstone technology in 3D metal printing. However, suitable small nozzles are hardly available, limiting the resolution and surface finish of final products. Here, the ejection of record-small metal droplets with a diameter of only 0.55±0.07 times the

  14. Towards Hybrid Online On-Demand Querying of Realtime Data with Stateful Complex Event Processing

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Qunzhi; Simmhan, Yogesh; Prasanna, Viktor K.

    2013-10-09

    Emerging Big Data applications in areas like e-commerce and energy industry require both online and on-demand queries to be performed over vast and fast data arriving as streams. These present novel challenges to Big Data management systems. Complex Event Processing (CEP) is recognized as a high performance online query scheme which in particular deals with the velocity aspect of the 3-V’s of Big Data. However, traditional CEP systems do not consider data variety and lack the capability to embed ad hoc queries over the volume of data streams. In this paper, we propose H2O, a stateful complex event processing framework, to support hybrid online and on-demand queries over realtime data. We propose a semantically enriched event and query model to address data variety. A formal query algebra is developed to precisely capture the stateful and containment semantics of online and on-demand queries. We describe techniques to achieve the interactive query processing over realtime data featured by efficient online querying, dynamic stream data persistence and on-demand access. The system architecture is presented and the current implementation status reported.

  15. Robustness of airline route networks

    Science.gov (United States)

    Lordan, Oriol; Sallan, Jose M.; Escorihuela, Nuria; Gonzalez-Prieto, David

    2016-03-01

    Airlines shape their route network by defining their routes through supply and demand considerations, paying little attention to network performance indicators, such as network robustness. However, the collapse of an airline network can produce high financial costs for the airline and all its geographical area of influence. The aim of this study is to analyze the topology and robustness of the network route of airlines following Low Cost Carriers (LCCs) and Full Service Carriers (FSCs) business models. Results show that FSC hubs are more central than LCC bases in their route network. As a result, LCC route networks are more robust than FSC networks.

  16. Optimised 'on demand' protein arraying from DNA by cell free expression with the 'DNA to Protein Array' (DAPA) technology.

    Science.gov (United States)

    Schmidt, Ronny; Cook, Elizabeth A; Kastelic, Damjana; Taussig, Michael J; Stoevesandt, Oda

    2013-08-02

    We have previously described a protein arraying process based on cell free expression from DNA template arrays (DNA Array to Protein Array, DAPA). Here, we have investigated the influence of different array support coatings (Ni-NTA, Epoxy, 3D-Epoxy and Polyethylene glycol methacrylate (PEGMA)). Their optimal combination yields an increased amount of detected protein and an optimised spot morphology on the resulting protein array compared to the previously published protocol. The specificity of protein capture was improved using a tag-specific capture antibody on a protein repellent surface coating. The conditions for protein expression were optimised to yield the maximum amount of protein or the best detection results using specific monoclonal antibodies or a scaffold binder against the expressed targets. The optimised DAPA system was able to increase by threefold the expression of a representative model protein while conserving recognition by a specific antibody. The amount of expressed protein in DAPA was comparable to those of classically spotted protein arrays. Reaction conditions can be tailored to suit the application of interest. DAPA represents a cost effective, easy and convenient way of producing protein arrays on demand. The reported work is expected to facilitate the application of DAPA for personalized medicine and screening purposes. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Plug-and-actuate on demand: multimodal individual addressability of microarray plates using modular hybrid acoustic wave technology.

    Science.gov (United States)

    Rezk, Amgad R; Ramesan, Shwathy; Yeo, Leslie Y

    2018-01-30

    The microarray titre plate remains a fundamental workhorse in genomic, proteomic and cellomic analyses that underpin the drug discovery process. Nevertheless, liquid handling technologies for sample dispensing, processing and transfer have not progressed significantly beyond conventional robotic micropipetting techniques, which are not only at their fundamental sample size limit, but are also prone to mechanical failure and contamination. This is because alternative technologies to date suffer from a number of constraints, mainly their limitation to carry out only a single liquid operation such as dispensing or mixing at a given time, and their inability to address individual wells, particularly at high throughput. Here, we demonstrate the possibility for true sequential or simultaneous single- and multi-well addressability in a 96-well plate using a reconfigurable modular platform from which MHz-order hybrid surface and bulk acoustic waves can be coupled to drive a variety of microfluidic modes including mixing, sample preconcentration and droplet jetting/ejection in individual or multiple wells on demand, thus constituting a highly versatile yet simple setup capable of improving the functionality of existing laboratory protocols and processes.

  18. In-memory interconnect protocol configuration registers

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Kevin Y.; Roberts, David A.

    2017-09-19

    Systems, apparatuses, and methods for moving the interconnect protocol configuration registers into the main memory space of a node. The region of memory used for storing the interconnect protocol configuration registers may also be made cacheable to reduce the latency of accesses to the interconnect protocol configuration registers. Interconnect protocol configuration registers which are used during a startup routine may be prefetched into the host's cache to make the startup routine more efficient. The interconnect protocol configuration registers for various interconnect protocols may include one or more of device capability tables, memory-side statistics (e.g., to support two-level memory data mapping decisions), advanced memory and interconnect features such as repair resources and routing tables, prefetching hints, error correcting code (ECC) bits, lists of device capabilities, set and store base address, capability, device ID, status, configuration, capabilities, and other settings.

  19. In-memory interconnect protocol configuration registers

    Science.gov (United States)

    Cheng, Kevin Y.; Roberts, David A.

    2017-09-19

    Systems, apparatuses, and methods for moving the interconnect protocol configuration registers into the main memory space of a node. The region of memory used for storing the interconnect protocol configuration registers may also be made cacheable to reduce the latency of accesses to the interconnect protocol configuration registers. Interconnect protocol configuration registers which are used during a startup routine may be prefetched into the host's cache to make the startup routine more efficient. The interconnect protocol configuration registers for various interconnect protocols may include one or more of device capability tables, memory-side statistics (e.g., to support two-level memory data mapping decisions), advanced memory and interconnect features such as repair resources and routing tables, prefetching hints, error correcting code (ECC) bits, lists of device capabilities, set and store base address, capability, device ID, status, configuration, capabilities, and other settings.

  20. Personal continuous route pattern mining

    Institute of Scientific and Technical Information of China (English)

    Qian YE; Ling CHEN; Gen-cai CHEN

    2009-01-01

    In the daily life, people often repeat regular routes in certain periods. In this paper, a mining system is developed to find the continuous route patterns of personal past trips. In order to count the diversity of personal moving status, the mining system employs the adaptive GPS data recording and five data filters to guarantee the clean trips data. The mining system uses a client/server architecture to protect personal privacy and to reduce the computational load. The server conducts the main mining procedure but with insufficient information to recover real personal routes. In order to improve the scalability of sequential pattern mining, a novel pattern mining algorithm, continuous route pattern mining (CRPM), is proposed. This algorithm can tolerate the different disturbances in real routes and extract the frequent patterns. Experimental results based on nine persons' trips show that CRPM can extract more than two times longer route patterns than the traditional route pattern mining algorithms.

  1. The extended TRIP supporting VoIP routing reservation with distributed QoS

    Science.gov (United States)

    Wang, Furong; Wu, Ye

    2004-04-01

    In this paper, an existing protocol, i.e. TRIP (Telephony Routing over IP) is developed to provide distributed QoS when making resource reservations for VoIP services such as H.323, SIP. Enhanced LSs (location servers) are deployed in ITADs (IP Telephony Administrative Domains) to take in charge of intra-domain routing policy because of small propagation price. It is an easy way to find an IP telephone route for intra-domain VoIP media association and simultaneously possess intra-domain load balancing features. For those routing reservations bridging domains, inter-domain routing policy is responsible for finding the shortest inter-domain route with enough resources. I propose the routing preference policy based on QoS price when the session traffic is shaped by a token bucket, related QoS messages, and message cooperation.

  2. Elisabeth Badinter, Fausse route

    OpenAIRE

    Martin-Juchat, Fabienne

    2013-01-01

    Elisabeth Badinter, philosophe de formation, est l’auteure de nombreux ouvrages sur la condition féminine et les rapports hommes/femmes dans la société. Avec Fausse route, elle signe une vision polémique du féminisme occidental. Son ouvrage a suscité de nombreuses critiques de femmes dans diverses revues destinées au grand public. Hélène Strohl, recenseur de la revue Culture en mouvement, conclut que cet ouvrage est peu scientifique, sujet à caution : « Argument contre argument, amalgame cont...

  3. An energy-aware engineered control plane for wavelength-routed networks

    DEFF Research Database (Denmark)

    Ricciardi, Sergio; Wang, Jiayuan; Palmieri, Francesco

    2015-01-01

    ' operational expenditures. To face this problem, we propose a single-stage routing and wavelength assignment scheme, based on several network engineering extensions to the Generalised Multi-Protocol Label Switching (GMPLS) control plane protocols, mainly Open Shortest Path First, with new composed metrics...

  4. PlayNCool: Opportunistic Network Coding for Local Optimization of Routing in Wireless Mesh Networks

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Roetter, Daniel Enrique Lucani; Pedersen, Morten Videbæk

    2013-01-01

    This paper introduces PlayNCool, an opportunistic protocol with local optimization based on network coding to increase the throughput of a wireless mesh network (WMN). PlayNCool aims to enhance current routing protocols by (i) allowing random linear network coding transmissions end-to-end, (ii) r...

  5. Formation of radial aligned and uniform nematic liquid crystal droplets via drop-on-demand inkjet printing into a partially-wet polymer layer

    Science.gov (United States)

    Parry, Ellis; Kim, Dong-Jin; Castrejón-Pita, Alfonso A.; Elston, Steve J.; Morris, Stephen M.

    2018-06-01

    This paper investigates the drop-on-demand inkjet printing of a nematic liquid crystal (LC) onto a variety of substrates. Achieving both a well-defined droplet boundary and uniformity of the LC director in printed droplets can be challenging when traditional alignment surfaces are employed. Despite the increasing popularity of inkjet printing LCs, the mechanisms that are involved during the deposition process such as drop impact, wetting and spreading have received very little attention, in the way of experiments, as viable routes for promoting alignment of the resultant LC droplets. In this work, radial alignment of the director and uniformity of the droplet boundary are achieved in combination via the use of a partially-wet polymer substrate, which makes use of the forces and flow generated during droplet impact and subsequent wetting process. Our findings could have important consequences for future LC inkjet applications, including the development of smart inks, printable sensors and lasers.

  6. Routing Service Quality—Local Driver Behavior Versus Routing Services

    DEFF Research Database (Denmark)

    Ceikute, Vaida; Jensen, Christian S.

    2013-01-01

    of the quality of one kind of location-based service, namely routing services. Specifically, the paper presents a framework that enables the comparison of the routes provided by routing services with the actual driving behaviors of local drivers. Comparisons include route length, travel time, and also route...... popularity, which are enabled by common driving behaviors found in available trajectory data. The ability to evaluate the quality of routing services enables service providers to improve the quality of their services and enables users to identify the services that best serve their needs. The paper covers......Mobile location-based services is a very successful class of services that are being used frequently by users with GPS-enabled mobile devices such as smartphones. This paper presents a study of how to exploit GPS trajectory data, which is available in increasing volumes, for the assessment...

  7. Cryptographic Protocols:

    DEFF Research Database (Denmark)

    Geisler, Martin Joakim Bittel

    cryptography was thus concerned with message confidentiality and integrity. Modern cryptography cover a much wider range of subjects including the area of secure multiparty computation, which will be the main topic of this dissertation. Our first contribution is a new protocol for secure comparison, presented...... implemented the comparison protocol in Java and benchmarks show that is it highly competitive and practical. The biggest contribution of this dissertation is a general framework for secure multiparty computation. Instead of making new ad hoc implementations for each protocol, we want a single and extensible...... in Chapter 2. Comparisons play a key role in many systems such as online auctions and benchmarks — it is not unreasonable to say that when parties come together for a multiparty computation, it is because they want to make decisions that depend on private information. Decisions depend on comparisons. We have...

  8. An Opportunistic Routing for Data Forwarding Based on Vehicle Mobility Association in Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Leilei Wang

    2017-11-01

    Full Text Available Vehicular ad hoc networks (VANETs have emerged as a new powerful technology for data transmission between vehicles. Efficient data transmission accompanied with low data delay plays an important role in selecting the ideal data forwarding path in VANETs. This paper proposes a new opportunity routing protocol for data forwarding based on vehicle mobility association (OVMA. With assistance from the vehicle mobility association, data can be forwarded without passing through many extra intermediate nodes. Besides, each vehicle carries the only replica information to record its associated vehicle information, so the routing decision can adapt to the vehicle densities. Simulation results show that the OVMA protocol can extend the network lifetime, improve the performance of data delivery ratio, and reduce the data delay and routing overhead when compared to the other well-known routing protocols.

  9. Dynamic QoS management in Differentiated Services using bandwidth brokers, RSVP aggregation and load control protocols

    NARCIS (Netherlands)

    Westberg, Lars; Eriksson, Anders; Karagiannis, Georgios; Heijenk, Geert; Rexhepi, Vlora; Partain, David

    2001-01-01

    A method and network subsystem for providing on demand end to end Quality of Service (Qos) in a dynamic manner, use a combination of Resource Reservation Protocol (RSVP), load control protocol (and its successors) and Bandwidth Brokers (BBs)(1106) which communicate using a predetermined protocol.

  10. Dynamic QoS management in Differentiated Services using bandwidth brokers, RSVP aggregation and load control protocols

    NARCIS (Netherlands)

    Westberg, Lars; Eriksson, Anders; Karagiannis, Georgios; Heijenk, Geert; Rexhepi, Vlora; Partain, David

    2009-01-01

    A method and network subsystem for providing on demand end to end Quality of Service (Qos) in a dynamic manner, use a combination of Resource Reservation Protocol (RSVP), load control protocol (and its successors) and Bandwidth Brokers (BBs)(1106) which communicate using a predetermined protocol.

  11. An overview of smart grid routing algorithms

    Science.gov (United States)

    Wang, Junsheng; OU, Qinghai; Shen, Haijuan

    2017-08-01

    This paper summarizes the typical routing algorithm in smart grid by analyzing the communication business and communication requirements of intelligent grid. Mainly from the two kinds of routing algorithm is analyzed, namely clustering routing algorithm and routing algorithm, analyzed the advantages and disadvantages of two kinds of typical routing algorithm in routing algorithm and applicability.

  12. Evaluation of RPL-compliant routing solutions in real-life WSNs

    Directory of Open Access Journals (Sweden)

    Zahariadis Theodore

    2016-01-01

    Full Text Available Wireless Sensor Networks (WSN applications continue to expand and already cover almost all our daily activities improving from security and environmental efficiency to gaming experience. The diverse applications running on top of WSNs have led to the design of an immense number of routing protocols. Few years ago, the IETF standardized the IPv6 routing protocol for low-power and lossy networks (RPL which is based on routing metrics to build communication paths between a source and the destination node. While significant efforts have focused on the design of routing metrics that satisfy the various applications, limited work has been reported on validating their performance using real-life motes. In this paper, we focus on validating the simulation results (obtained through the JSim simulator using TelosB motes for a set of routing metrics that have been proposed in our previous articles.

  13. Minecraft® on Demand - A new IGN service which combines game and 3D cartography

    Science.gov (United States)

    Lecordix, François; Fremont, David; Jilani, Moez; Séguin, Emmanuel; Kriat, Sofiane

    2018-05-01

    The French national mapping agency, Institut national de l'information géographique et forestière (IGN), decided to develop a new web service, called Minecraft on Demand (www.ign.fr/Minecraft), designed to provide Minecraft maps from the geographic data that IGN produces. This free web service enables the user to select the center of the map and to get a Minecraft world of 5 km long and 5 km wide, at the scale 1 : 1. The player can easily input this map into Minecraft, the world's most popular video game with 121 million copies sold. Launched in June 2016 in France, the service Minecraft® on Demand obtained a fair success (10,000 maps downloaded), more specifically among young people, since it may enable them to discover IGN data and geography.

  14. Database on Demand: insight how to build your own DBaaS

    CERN Document Server

    Aparicio, Ruben Gaspar

    2015-01-01

    At CERN, a number of key database applications are running on user-managed MySQL, PostgreSQL and Oracle database services. The Database on Demand (DBoD) project was born out of an idea to provide CERN user community with an environment to develop and run database services as a complement to the central Oracle based database service. The Database on Demand empowers the user to perform certain actions that had been traditionally done by database administrators, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently three major RDBMS (relational database management system) vendors are offered. In this article we show the actual status of the service after almost three years of operations, some insight of our new redesign software engineering and near future evolution.

  15. Exploring Concepts of Operations for On-Demand Passenger Air Transportation

    Science.gov (United States)

    Nneji, Victoria Chibuogu; Stimpson, Alexander; Cummings, Mary; Goodrich, Kenneth H.

    2017-01-01

    In recent years, a surge of interest in "flying cars" for city commutes has led to rapid development of new technologies to help make them and similar on-demand mobility platforms a reality. To this end, this paper provides analyses of the stakeholders involved, their proposed operational concepts, and the hazards and regulations that must be addressed. Three system architectures emerged from the analyses, ranging from conventional air taxi to revolutionary fully autonomous aircraft operations, each with vehicle safety functions allocated differently between humans and machines. Advancements for enabling technologies such as distributed electric propulsion and artificial intelligence have had major investments and initial experimental success, but may be some years away from being deployed for on-demand passenger air transportation at scale.

  16. Web-based nephropathology teaching modules and user satisfaction: the nephrology on-demand experience.

    Science.gov (United States)

    Desai, Tejas; Talento, Romualdo; Christiano, Cynthia; Ferris, Maria; Hewan-Lowe, Karlene

    2011-01-01

    Nephropathology is an integral component of nephrology education. Online teaching sites provide valuable educational materials to learners, but learner satisfaction has not been measured. We developed a nephropathology website and measured learners' satisfaction. The Nephrology On-Demand Histopathology website (http://blog.ecu.edu/sites/nephrologyondemand/?page_id=4502) provided nephropathologic specimens with explanations. Users were asked to complete a Likert-based survey (1-strongly agree . . . 5-strongly disagree) regarding four key areas of content quality: accuracy, currency, objectivity, and usefulness. Learners of all training levels perceived the content quality favorably. The mean (±SD) for accuracy was 1.70 (0.89), currency 1.62 (0.90), objectivity 1.80 (1.01), and usefulness 1.72 (0.95). Nephrology On-Demand Histopathology is a well-received teaching tool to learners of all training levels. Educators may consider using it, as well as other online nephropathology sites, as adjunctive teaching tools.

  17. Database on Demand: insight how to build your own DBaaS

    Science.gov (United States)

    Gaspar Aparicio, Ruben; Coterillo Coz, Ignacio

    2015-12-01

    At CERN, a number of key database applications are running on user-managed MySQL, PostgreSQL and Oracle database services. The Database on Demand (DBoD) project was born out of an idea to provide CERN user community with an environment to develop and run database services as a complement to the central Oracle based database service. The Database on Demand empowers the user to perform certain actions that had been traditionally done by database administrators, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently three major RDBMS (relational database management system) vendors are offered. In this article we show the actual status of the service after almost three years of operations, some insight of our new redesign software engineering and near future evolution.

  18. Adaptive Relay Activation in the Network Coding Protocols

    DEFF Research Database (Denmark)

    Pahlevani, Peyman; Roetter, Daniel Enrique Lucani; Fitzek, Frank

    2015-01-01

    State-of-the-art Network coding based routing protocols exploit the link quality information to compute the transmission rate in the intermediate nodes. However, the link quality discovery protocols are usually inaccurate, and introduce overhead in wireless mesh networks. In this paper, we presen...

  19. Impact of Mobility-on-Demand on Traffic Congestion: Simulation-based Study

    OpenAIRE

    Fiedler, David; Čáp, Michal; Čertický, Michal

    2017-01-01

    The increasing use of private vehicles for transportation in cities results in a growing demand for parking space and road network capacity. In many densely populated urban areas, however, the capacity of existing infrastructure is insufficient and extremely difficult to expand. Mobility-on-demand systems have been proposed as a remedy to the problem of limited parking space because they are able to satisfy the existing transportation demand with fewer shared vehicles and consequently require...

  20. Architectural Considerations for Highly Scalable Computing to Support On-demand Video Analytics

    Science.gov (United States)

    2017-04-19

    research were used to implement a distributed on-demand video analytics system that was prototyped for the use of forensics investigators in law...demand video intelligence; intelligent video system ; video analytics platform I. INTRODUCTION Video Analytics systems has been of tremendous interest...enforcement. The system was tested in the wild using video files as well as a commercial Video Management System supporting more than 100 surveillance

  1. On-Demand Dark Soliton Train Manipulation in a Spinor Polariton Condensate

    KAUST Repository

    Pinsker, F.

    2014-04-10

    We theoretically demonstrate the generation of dark soliton trains in a one-dimensional exciton-polariton condensate within experimentally accessible schemes. In particular, we show that the frequency of the train can be finely tuned fully optically or electrically to provide a stable and efficient output signal modulation. Taking the polarization of the condensate into account, we elucidate the possibility of forming on-demand half-soliton trains. © 2014 American Physical Society.

  2. On-Demand Treatment of Premature Ejaculation with Citalopram: A Randomized Double-Blind Study

    Directory of Open Access Journals (Sweden)

    Ghafuri Zahra

    2009-10-01

    Full Text Available "nAs the most common male sexual disorder premature ejaculation (PE, also referred to as early ejaculation (EE or rapid ejaculation (RE, affects 30%-40% of sexually active men. Despite the limited number of available studies comparing the efficacy of selective serotonin re-uptake inhibitors (SSRI they have been thought to have beneficial effects for the treatment of patients with PE. In the present study, we assessed the efficacy of on-demand use of citalopram, in the treatment of premature ejaculation. A randomized double blind study of fixed dose on-demand use of citalopram was performed in Roozbeh Psychiatry Hospital, Tehran University of Medical Sciences. The sample was consisted of 80 married patients diagnosed with PE according to Diagnostic and Statistical Manual of Mental Disorders. The patients were randomly assigned to two groups: group 1 consisting of 42 patients received 20mg citalopram, and group 2 consisting of 38 patients received placebo four hours before intercourse for a 4-week treatment course. The effects of drug on the ejaculatory function in each group were assessed by the intravaginal ejaculation latency time (IELT, and the Chinese Index of Premature Ejaculation (CIPE before and at the end of treatment course. The mean IELT increased from 66.78±36.94 to 80.85±43.05 seconds in group 1 and from 63.44±33.16 to 65.71±34.26 seconds in group 2 (P = 0.000. Mean CIPE score increased 1.14±1.04 and 0.52±0.50 in group 1 and 2 respectively (P = 0.002. The patients treated with on demand citalopram showed significantly greater improvement in IELT and CIPE score compared to the patients receiving placebo. It seems that citalopram may be an effective treatment of premature ejaculation with on-demand usage. However further studies are warranted.

  3. On Demand Internal Short Circuit Device Enables Verification of Safer, Higher Performing Battery Designs

    Energy Technology Data Exchange (ETDEWEB)

    Darcy, Eric; Keyser, Matthew

    2017-05-15

    The Internal Short Circuit (ISC) device enables critical battery safety verification. With the aluminum interstitial heat sink between the cells, normal trigger cells cannot be driven into thermal runaway without excessive temperature bias of adjacent cells. With an implantable, on-demand ISC device, thermal runaway tests show that the conductive heat sinks protected adjacent cells from propagation. High heat dissipation and structural support of Al heat sinks show high promise for safer, higher performing batteries.

  4. Piracy versus Netflix : Subscription Video on Demand Dissatisfaction as an Antecedent of Piracy

    OpenAIRE

    Riekkinen, Janne

    2018-01-01

    Drawing from cognitive dissonance and neutralization theories, this study seeks to improve the understanding on consumer decision-making between the current legal and illegal video consumption alternatives. We develop and test a research model featuring Subscription Video on Demand (SVOD) satisfaction and various dimensions of SVOD quality as antecedents of video piracy neutralizations and attitudes. Based on results from an online survey among Finnish SVOD users, SVOD satisfaction is primari...

  5. Design and control of precision drop-on-demand herbicide application in agricultural robotics

    OpenAIRE

    Urdal, Frode; Utstumo, Trygve; Vatne, Jan Kåre; Ellingsen, Simen Andreas Ådnøy; Gravdahl, Jan Tommy

    2014-01-01

    This is the author’s final, accepted and refereed manuscript to the article. Drop-on-demand weed control is a field of research within Precision Agriculture, where the herbicide application is controlled down to individual droplets. This paper focuses on the fluid dynamics and electronics design of the droplet dispensing. The droplets are formed through an array of nozzles, controlled by two-way solenoid valves. A much used control circuit for opening and closing a soleno...

  6. Comparing image quality of print-on-demand books and photobooks from web-based vendors

    Science.gov (United States)

    Phillips, Jonathan; Bajorski, Peter; Burns, Peter; Fredericks, Erin; Rosen, Mitchell

    2010-01-01

    Because of the emergence of e-commerce and developments in print engines designed for economical output of very short runs, there are increased business opportunities and consumer options for print-on-demand books and photobooks. The current state of these printing modes allows for direct uploading of book files via the web, printing on nonoffset printers, and distributing by standard parcel or mail delivery services. The goal of this research is to assess the image quality of print-on-demand books and photobooks produced by various Web-based vendors and to identify correlations between psychophysical results and objective metrics. Six vendors were identified for one-off (single-copy) print-on-demand books, and seven vendors were identified for photobooks. Participants rank ordered overall quality of a subset of individual pages from each book, where the pages included text, photographs, or a combination of the two. Observers also reported overall quality ratings and price estimates for the bound books. Objective metrics of color gamut, color accuracy, accuracy of International Color Consortium profile usage, eye-weighted root mean square L*, and cascaded modulation transfer acutance were obtained and compared to the observer responses. We introduce some new methods for normalizing data as well as for strengthening the statistical significance of the results. Our approach includes the use of latent mixed-effect models. We found statistically significant correlation with overall image quality and some of the spatial metrics, but correlations between psychophysical results and other objective metrics were weak or nonexistent. Strong correlation was found between psychophysical results of overall quality assessment and estimated price associated with quality. The photobook set of vendors reached higher image-quality ratings than the set of print-on-demand vendors. However, the photobook set had higher image-quality variability.

  7. Immunochemical protocols

    National Research Council Canada - National Science Library

    Pound, John D

    1998-01-01

    ... easy and important refinements often are not published. This much anticipated 2nd edition of Immunochemzcal Protocols therefore aims to provide a user-friendly up-to-date handbook of reliable techniques selected to suit the needs of molecular biologists. It covers the full breadth of the relevant established immunochemical methods, from protein blotting and immunoa...

  8. Delivery of video-on-demand services using local storages within passive optical networks.

    Science.gov (United States)

    Abeywickrama, Sandu; Wong, Elaine

    2013-01-28

    At present, distributed storage systems have been widely studied to alleviate Internet traffic build-up caused by high-bandwidth, on-demand applications. Distributed storage arrays located locally within the passive optical network were previously proposed to deliver Video-on-Demand services. As an added feature, a popularity-aware caching algorithm was also proposed to dynamically maintain the most popular videos in the storage arrays of such local storages. In this paper, we present a new dynamic bandwidth allocation algorithm to improve Video-on-Demand services over passive optical networks using local storages. The algorithm exploits the use of standard control packets to reduce the time taken for the initial request communication between the customer and the central office, and to maintain the set of popular movies in the local storage. We conduct packet level simulations to perform a comparative analysis of the Quality-of-Service attributes between two passive optical networks, namely the conventional passive optical network and one that is equipped with a local storage. Results from our analysis highlight that strategic placement of a local storage inside the network enables the services to be delivered with improved Quality-of-Service to the customer. We further formulate power consumption models of both architectures to examine the trade-off between enhanced Quality-of-Service performance versus the increased power requirement from implementing a local storage within the network.

  9. Vertex routing models

    International Nuclear Information System (INIS)

    Markovic, D; Gros, C

    2009-01-01

    A class of models describing the flow of information within networks via routing processes is proposed and investigated, concentrating on the effects of memory traces on the global properties. The long-term flow of information is governed by cyclic attractors, allowing to define a measure for the information centrality of a vertex given by the number of attractors passing through this vertex. We find the number of vertices having a nonzero information centrality to be extensive/subextensive for models with/without a memory trace in the thermodynamic limit. We evaluate the distribution of the number of cycles, of the cycle length and of the maximal basins of attraction, finding a complete scaling collapse in the thermodynamic limit for the latter. Possible implications of our results for the information flow in social networks are discussed.

  10. Southern states' routing agency report

    International Nuclear Information System (INIS)

    1989-02-01

    The Southern states' routing agency report is a compendium of 16-southern states' routing programs relative to the transportation of high-level radioactive materials. The report identifies the state-designated routing agencies as defined under 49 Code of Federal Regulations (CFR) Part 171 and provides a reference to the source ad scope of the agencies' rulemaking authority. Additionally, the state agency and contact designated by the state's governor to receive advance notification and shipment routing information under 10 CFR Parts 71 and 73 are also listed

  11. Southern States' Routing Agency Report

    International Nuclear Information System (INIS)

    1990-03-01

    The Southern States' Routing Agency Report is a compendium of 16-southern states' routing program for the transportation of high-level radioactive materials. The report identifies the state-designated routing agencies as defined under 49 Code of Federal Regulations (CFR) Part 171 and provides a reference to the source and scope of the agencies' rulemaking authority. Additionally, the state agency and contact designated by the state's governor to receive advance notification and shipment routing information under 10 CFR Parts 71 and 73 are also listed

  12. Implementing Head and Neck Contouring Peer Review without Pathway Delay: The On-demand Approach.

    Science.gov (United States)

    Fong, C; Sanghera, P; Good, J; Nightingale, P; Hartley, A

    2017-12-01

    Peer review of contour volume is a priority in the radiotherapy treatment quality assurance process for head and neck cancer. It is essential that incorporation of peer review activity does not introduce additional delays. An on-demand peer review process was piloted to assess the feasibility and efficiency of this approach, as compared with a historic scheduled weekly approach. Between November 2016 and April 2017 four head and neck clinicians in one centre took part in an on-demand peer review process. Cases were of radical or adjuvant intent of any histology and submitted on a voluntary basis. The outcome of contour peer review would be one of unchanged (UC), unchanged with variation or discretion noted (UV), minor change (M) or significant change (S). The time difference between the completion of the on-demand peer review was compared with the time difference to a hypothetical next Monday or Tuesday weekly peer review meeting. The time taken to review each case was also documented in the latter period of the pilot project. In total, 62 cases underwent peer review. Peer review on-demand provided dosimetrists with an average of an extra two working days available per case to meet treatment start dates. The proportion of cases with outcomes UC, UV, M and S were 45%, 16%, 26% and 13%, respectively. The mean peer review time spent per case was 17 min (12 cases). The main reason for S was discrepancy in imaging interpretation (4/8 cases). A lower proportion of oropharyngeal cases were submitted and had S outcomes. A higher proportion of complex cases, e.g. sinonasal/nasopharynx location or previous downstaging chemotherapy had S outcomes. The distribution of S outcomes appears to be similar regardless of clinician experience. The level of peer review activity among individuals differed by workload and job timetable. On-demand peer review of the head and neck contour volume is feasible, reduces delay to the start of dosimetry planning and bypasses the logistical

  13. Secure Trust Based Key Management Routing Framework for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jugminder Kaur

    2016-01-01

    Full Text Available Security is always a major concern in wireless sensor networks (WSNs. Several trust based routing protocols are designed that play an important role in enhancing the performance of a wireless network. However they still have some disadvantages like limited energy resources, susceptibility to physical capture, and little protection against various attacks due to insecure wireless communication channels. This paper presents a secure trust based key management (STKF routing framework that establishes a secure trustworthy route depending upon the present and past node to node interactions. This route is then updated by isolating the malicious or compromised nodes from the route, if any, and a dedicated link is created between every pair of nodes in the selected route with the help of “q” composite random key predistribution scheme (RKPS to ensure data delivery from source to destination. The performance of trust aware secure routing framework (TSRF is compared with the proposed routing scheme. The results indicate that STKF provides an effective mechanism for finding out a secure route with better trustworthiness than TSRF which avoids the data dropping, thereby increasing the data delivery ratio. Also the distance required to reach the destination in the proposed protocol is less hence effectively utilizing the resources.

  14. A Cross-Layer Route Discovery Framework for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Wu Jieyi

    2005-01-01

    Full Text Available Most reactive routing protocols in MANETs employ a random delay between rebroadcasting route requests (RREQ in order to avoid "broadcast storms." However this can lead to problems such as "next hop racing" and "rebroadcast redundancy." In addition to this, existing routing protocols for MANETs usually take a single routing strategy for all flows. This may lead to inefficient use of resources. In this paper we propose a cross-layer route discovery framework (CRDF to address these problems by exploiting the cross-layer information. CRDF solves the above problems efficiently and enables a new technique: routing strategy automation (RoSAuto. RoSAuto refers to the technique that each source node automatically decides the routing strategy based on the application requirements and each intermediate node further adapts the routing strategy so that the network resource usage can be optimized. To demonstrate the effectiveness and the efficiency of CRDF, we design and evaluate a macrobian route discovery strategy under CRDF.

  15. SIMULASI INTERKONEKSI ANTARA AUTONOMOUS SYSTEM (AS MENGGUNAKAN BORDER GATEWAY PROTOCOL (BGP

    Directory of Open Access Journals (Sweden)

    Hari Antoni Musril

    2017-09-01

    Full Text Available An autonomous system (AS is the collection of networks having the same set of routing policies. Each AS has administrative control to its own inter-domain routing policy. Computer networks consisting of a bunch of AS's with different routing will not be able to interconnecttion one another. This is causes communication in the network to be inhibited. For that we need a protocol that can connect each different AS. Border Gateway Protocol (BGP is an inter-domain routing protocol i.e. between different AS  that is used to exchange routing information between them. In a typical inter-network (and in the Internet each autonomous system designates one or more routers that run BGP software. BGP routers in each AS are linked to those in one or more other AS. The ability to exchange table routing information between Autonomous System (AS is one of the advantages BGP. BGP implements routing policies based a set of attributes accompanying each route used to pick the “shortest” path across multiple ASs, along with one or more routing policies. BGP uses an algorithm which cannot be classified as a pure "Distance Vector", or pure "Link State". It is a path vector routing protocol as it defines a route as a collection of a number of AS that is passes through from source AS to destination AS. This paper discusses the implementation of the BGP routing protocol in the network that have different AS in order to interconnect. Its application using Packet Tracer 7.0 software for prototyping and simulating network. So that later can be applied to the actual network. Based on experiments that have been carried out, the BGP routing protocol can connect two routers that have different autonomous system.

  16. Performance of amplify-and-forward multihop transmission over relay clusters with different routing strategies

    KAUST Repository

    Yilmaz, Ferkan; Khan, Fahd Ahmed; Alouini, Mohamed-Slim

    2014-01-01

    We consider a multihop relay network in which two terminals are communicating with each other via a number of cluster of relays. Performance of such networks depends on the routing protocols employed. In this paper, we find the expressions for the Average Symbol Error Probability (ASEP) performance of Amplify-and-Forward (AF) multihop transmission for the simplest routing protocol in which the relay transmits using the channel having the best Signal to Noise Ratio (SNR). The ASEP performance of a better protocol proposed in Gui et al. (2009) known as the adhoc protocol is also analyzed. The derived expressions for the performance are a convenient tool to analyze the performance of AF multihop transmission over relay clusters. Monte-Carlo simulations verify the correctness of the proposed formulation and are in agreement with analytical results. Furthermore, we propose new generalized protocols termed as last-nhop selection protocol, the dual path protocol, the forward-backward last-n-hop selection protocol and the forward-backward dual path protocol, to get improved ASEP performances. The ASEP performance of these proposed schemes is analysed by computer simulations. It is shown that close to optimal performance can be achieved by using the last-n-hop selection protocol and its forwardbackward variant. The complexity of the protocols is also studied. Copyright © 2014 Inderscience Enterprises Ltd.

  17. Stochastic vehicle routing with recourse

    DEFF Research Database (Denmark)

    Gørtz, Inge Li; Nagarajan, Viswanath; Saket, Rishi

    2012-01-01

    instantiations, a recourse route is computed - but costs here become more expensive by a factor λ. We present an O(log2n ·log(nλ))-approximation algorithm for this stochastic routing problem, under arbitrary distributions. The main idea in this result is relating StochVRP to a special case of submodular...

  18. Route-external and route-internal landmarks in route descriptions : Effects of route length and map design

    NARCIS (Netherlands)

    Westerbeek, Hans; Maes, Alfons

    2013-01-01

    Landmarks are basic ingredients in route descriptions. They often mark choice points: locations where travellers choose from different options how to continue the route. This study focuses on one of the loose ends in the taxonomy of landmarks. In a memory-based production experiment in which

  19. Perception bias in route choice

    NARCIS (Netherlands)

    Vreeswijk, Jacob Dirk; Thomas, Tom; van Berkum, Eric C.; van Arem, Bart

    2014-01-01

    Travel time is probably one of the most studied attributes in route choice. Recently, perception of travel time received more attention as several studies have shown its importance in explaining route choice behavior. In particular, travel time estimates by travelers appear to be biased against

  20. Secure Geographic Routing in Ad Hoc and Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Zahariadis Theodore

    2010-01-01

    Full Text Available Security in sensor networks is one of the most relevant research topics in resource constrained wireless devices and networks. Several attacks can be suffered in ad hoc and wireless sensor networks (WSN, which are highly susceptible to attacks, due to the limited resources of the nodes. In this paper, we propose innovative and lightweight localization techniques that allow for intrusion identification and isolation schemes and provide accurate location information. This information is used by our routing protocol which additionally incorporates a distributed trust model to prevent several routing attacks to the network. We finally evaluate our algorithms for accurate localization and for secure routing which have been implemented and tested in real ad hoc and wireless sensor networks.

  1. Comparison of on-demand vs planned relaparotomy strategy in patients with severe peritonitis: a randomized trial

    NARCIS (Netherlands)

    van Ruler, Oddeke; Mahler, Cecilia W.; Boer, Kimberly R.; Reuland, E. Ascelijn; Gooszen, Hein G.; Opmeer, Brent C.; de Graaf, Peter W.; Lamme, Bas; Gerhards, Michael F.; Steller, E. Philip; van Till, J. W. Olivier; de Borgie, Corianne J. A. M.; Gouma, Dirk J.; Reitsma, Johannes B.; Boermeester, Marja A.

    2007-01-01

    CONTEXT: In patients with severe secondary peritonitis, there are 2 surgical treatment strategies following an initial emergency laparotomy: planned relaparotomy and relaparotomy only when the patient's condition demands it ("on-demand"). The on-demand strategy may reduce mortality, morbidity,

  2. Whirlpool routing for mobility

    KAUST Repository

    Lee, Jung Woo; Kusy, Branislav; Azim, Tahir; Shihada, Basem; Levis, Philip

    2010-01-01

    Using simulation, controlled testbeds, and real mobility experiments, we find that using the data plane for topology maintenance is highly effective due to the incremental nature of mobility updates. WARP leverages the fact that converging flows at a destination make the destination have the region of highest traffic. We provide a theoretical basis for WARP's behavior, defining an "update area" in which the topology must adjust when a destination moves. As long as packets arrive at a destination before it moves outside of the update area, WARP can repair the topology using the data plane. Compared to existing protocols, such as DYMO and HYPER, WARP's packet drop rate is up to 90% lower while sending up to 90% fewer packets.

  3. Nutrition and Hyperglycemia Management in the Inpatient Setting (Meals on Demand, Parenteral, or Enteral Nutrition).

    Science.gov (United States)

    Drincic, Andjela T; Knezevich, Jon T; Akkireddy, Padmaja

    2017-08-01

    The goal of this paper is to provide the latest evidence and expert recommendations for management of hospitalized patients with diabetes or hyperglycemia receiving enteral (EN), parenteral (PN) nutrition support or, those with unrestricted oral diet, consuming meals on demand. Patients with and without diabetes mellitus commonly develop hyperglycemia while receiving EN or PN support, placing them at increased risk of adverse outcomes, including in-hospital mortality. Very little new evidence is available in the form of randomized controlled trials (RCT) to guide the glycemic management of these patients. Reduction in the dextrose concentration within parenteral nutrition as well as selection of an enteral formula that diminishes the carbohydrate exposure to a patient receiving enteral nutrition are common strategies utilized in practice. No specific insulin regimen has been shown to be superior in the management of patients receiving EN or PN nutrition support. For those receiving oral nutrition, new challenges have been introduced with the most recent practice allowing patients to eat meals on demand, leading to extreme variability in carbohydrate exposure and risk of hypo and hyperglycemia. Synchronization of nutrition delivery with the astute use of intravenous or subcutaneous insulin therapy to match the physiologic action of insulin in patients receiving nutritional support should be implemented to improve glycemic control in hospitalized patients. Further RCTs are needed to evaluate glycemic and other clinical outcomes of patients receiving nutritional support. For patients eating meals on demand, development of hospital guidelines and policies are needed, ensuring optimization and coordination of meal insulin delivery in order to facilitate patient safety.

  4. A Bioinspired Adaptive Congestion-Avoidance Routing for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Huang Qiong

    2014-01-01

    Full Text Available Traditional mobile Ad Hoc network routing protocols are mainly based on the Shortest Path, which possibly results in many congestion nodes that incur routing instability and rerouting. To mitigate the side-efforts, this paper proposed a new bioinspired adaptive routing protocol (ATAR based on a mathematics biology model ARAS. This paper improved the ARAS by reducing the randomness and by introducing a new routing-decision metric “the next-hop fitness” which was denoted as the congestion level of node and the length of routing path. In the route maintenance, the nodes decide to forward the data to next node according to a threshold value of the fitness. In the recovery phase, the node will adopt random manner to select the neighbor as the next hop by calculation of the improved ARAS. With this route mechanism, the ATAR could adaptively circumvent the congestion nodes and the rerouting action is taken in advance. Theoretical analysis and numerical simulation results show that the ATAR protocol outperforms AODV and MARAS in terms of delivery ratio, ETE delay, and the complexity. In particular, ATAR can efficiently mitigate the congestion.

  5. AIB-OR: improving onion routing circuit construction using anonymous identity-based cryptosystems.

    Science.gov (United States)

    Wang, Changji; Shi, Dongyuan; Xu, Xilei

    2015-01-01

    The rapid growth of Internet applications has made communication anonymity an increasingly important or even indispensable security requirement. Onion routing has been employed as an infrastructure for anonymous communication over a public network, which provides anonymous connections that are strongly resistant to both eavesdropping and traffic analysis. However, existing onion routing protocols usually exhibit poor performance due to repeated encryption operations. In this paper, we first present an improved anonymous multi-receiver identity-based encryption (AMRIBE) scheme, and an improved identity-based one-way anonymous key agreement (IBOWAKE) protocol. We then propose an efficient onion routing protocol named AIB-OR that provides provable security and strong anonymity. Our main approach is to use our improved AMRIBE scheme and improved IBOWAKE protocol in onion routing circuit construction. Compared with other onion routing protocols, AIB-OR provides high efficiency, scalability, strong anonymity and fault tolerance. Performance measurements from a prototype implementation show that our proposed AIB-OR can achieve high bandwidths and low latencies when deployed over the Internet.

  6. WEAMR — A Weighted Energy Aware Multipath Reliable Routing Mechanism for Hotline-Based WSNs

    Directory of Open Access Journals (Sweden)

    Ki-Hyung Kim

    2013-05-01

    Full Text Available Reliable source to sink communication is the most important factor for an efficient routing protocol especially in domains of military, healthcare and disaster recovery applications. We present weighted energy aware multipath reliable routing (WEAMR, a novel energy aware multipath routing protocol which utilizes hotline-assisted routing to meet such requirements for mission critical applications. The protocol reduces the number of average hops from source to destination and provides unmatched reliability as compared to well known reactive ad hoc protocols i.e., AODV and AOMDV. Our protocol makes efficient use of network paths based on weighted cost calculation and intelligently selects the best possible paths for data transmissions. The path cost calculation considers end to end number of hops, latency and minimum energy node value in the path. In case of path failure path recalculation is done efficiently with minimum latency and control packets overhead. Our evaluation shows that our proposal provides better end-to-end delivery with less routing overhead and higher packet delivery success ratio compared to AODV and AOMDV. The use of multipath also increases overall life time of WSN network using optimum energy available paths between sender and receiver in WDNs.

  7. Streamlining On-Demand Access to Joint Polar Satellite System (JPSS) Data Products for Weather Forecasting

    Science.gov (United States)

    Evans, J. D.; Tislin, D.

    2017-12-01

    Observations from the Joint Polar Satellite System (JPSS) support National Weather Service (NWS) forecasters, whose Advanced Weather Interactive Processing System (AWIPS) Data Delivery (DD) will access JPSS data products on demand from the National Environmental Satellite, Data, and Information Service (NESDIS) Product Distribution and Access (PDA) service. Based on the Open Geospatial Consortium (OGC) Web Coverage Service, this on-demand service promises broad interoperability and frugal use of data networks by serving only the data that a user needs. But the volume, velocity, and variety of JPSS data products impose several challenges to such a service. It must be efficient to handle large volumes of complex, frequently updated data, and to fulfill many concurrent requests. It must offer flexible data handling and delivery, to work with a diverse and changing collection of data, and to tailor its outputs into products that users need, with minimal coordination between provider and user communities. It must support 24x7 operation, with no pauses in incoming data or user demand; and it must scale to rapid changes in data volume, variety, and demand as new satellites launch, more products come online, and users rely increasingly on the service. We are addressing these challenges in order to build an efficient and effective on-demand JPSS data service. For example, on-demand subsetting by many users at once may overload a server's processing capacity or its disk bandwidth - unless alleviated by spatial indexing, geolocation transforms, or pre-tiling and caching. Filtering by variable (/ band / layer) may also alleviate network loads, and provide fine-grained variable selection; to that end we are investigating how best to provide random access into the variety of spatiotemporal JPSS data products. Finally, producing tailored products (derivatives, aggregations) can boost flexibility for end users; but some tailoring operations may impose significant server loads

  8. Towards Organs on Demand: Breakthroughs and Challenges in Models of Organogenesis.

    Science.gov (United States)

    Francipane, Maria Giovanna; Lagasse, Eric

    2016-09-01

    In recent years, functional three-dimensional (3D) tissue generation in vitro has been significantly advanced by tissue-engineering methods, achieving better reproduction of complex native organs compared to conventional culture systems. This review will discuss traditional 3D cell culture techniques as well as newly developed technology platforms. These recent techniques provide new possibilities in the creation of human body parts and provide more accurate predictions of tissue response to drug and chemical challenges. Given the rapid advancement in the human induced pluripotent stem cell (iPSC) field, these platforms also hold great promise in the development of patient-specific, transplantable tissues and organs on demand.

  9. The digital laser: on-demand laser modes with the click of a button

    CSIR Research Space (South Africa)

    Forbes, A

    2014-02-01

    Full Text Available stream_source_info Forbes_2014_ABSTRACT ONLY.pdf.txt stream_content_type text/plain stream_size 729 Content-Encoding UTF-8 stream_name Forbes_2014_ABSTRACT ONLY.pdf.txt Content-Type text/plain; charset=UTF-8 The digital... laser: on-demand laser modes with the click of a button Forbes A, Ngcobo S, Burger L and Litvin IA ABSTRACT In this paper we will outline our recent advances in all-digital control of light. Importantly, we will outline how to create a so...

  10. Energy efficient ventilation based on demand humidity control. Demonstration project with 49 apartments in Soenderborg

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    The aim of the project is to demonstrate how the overall energy consumption in apartment buildings can be reduced through a combination of: 1) Energy efficient ventilation based on demand humidity control; 2) Energy efficient design of the building shell including passive solar and seasonally flexible sunspaces; 3) Use of low temperature heating system. The 3 blocks in the project, each with 16 apartments, are furnished with 3 different ventilation systems: 1) Standard exhaust system according to building codes; 2) Ventilation system with humidity control. Each room is furnished with an air inlet valve controlled by a processor, which monitors the humidity; 3) Standard ventilation system with heat recovery. (au)

  11. Opportunistic Wireless Charging System Design for an On-Demand Shuttle Service

    Energy Technology Data Exchange (ETDEWEB)

    Meintz, Andrew; Doubleday, Kate; Markel, Tony

    2016-06-29

    System right-sizing is critical to the implementation of in-motion wireless power transfer (WPT) for electric vehicles. This study evaluates potential system designs for an on-demand employee shuttle by determining the required battery size based on the rated power at a variable number of charging locations. Vehicle power and state of charge are simulated over the drive cycle, based on position and velocity data at every second from the existing shuttle. Adding just one WPT location can halve the battery size. Many configurations are capable of self-sustaining with WPT, while others benefit from supplemental stationary charging.

  12. Efficient Routing in Wireless Sensor Networks with Multiple Sessions

    Directory of Open Access Journals (Sweden)

    Dianjie Lu

    2014-05-01

    Full Text Available Wireless Sensor Networks (WSNs are subject to node failures because of limited energy and link unreliability which makes the design of routing protocols in such networks a challenging task. The multipath routing scheme is an optimal alternative to address this problem which splits the traffic across multiple paths instead of routing all the traffic along a single path. However, using more paths introduces more contentions which degrade energy efficiency. The problem becomes even more difficult in the scenario of multiple sessions since different source-destination pairs may pass the same link which makes the flow distribution of each link uncertain. Our goal is to minimize the energy cost and provide the robust transmission by choosing the optimal paths. We first study the problem from a theoretical standpoint by mapping it to the multi-commodity network design problem. Since it is hard to build a global addressing scheme due to the great number of sensor nodes, we propose a Distributed Energy Efficient Routing protocol (D2ER. In D2ER, we employ the transportation method which can optimize the flow distribution with minimal energy consumption. Simulation results demonstrate that our optimal algorithm can save energy drastically.

  13. A Review of Vehicle to Vehicle Communication Protocols for VANETs in the Urban Environment

    Directory of Open Access Journals (Sweden)

    Irshad Ahmed Abbasi

    2018-01-01

    Full Text Available Vehicular Ad-hoc Networks (VANETs have been gaining significant attention from the research community due to their increasing importance for building an intelligent transportation system. The characteristics of VANETs, such as high mobility, network partitioning, intermittent connectivity and obstacles in city environments, make routing a challenging task. Due to these characteristics of VANETs, the performance of a routing protocol is degraded. The position-based routing is considered to be the most significant approach in VANETs. In this paper, we present a brief review of most significant position based unicast routing protocols designed for vehicle to vehicle communications in the urban environment. We provide them with their working features for exchanging information between vehicular nodes. We describe their pros and cons. This study also provides a comparison of the vehicle to vehicle communication based routing protocols. The comparative study is based on some significant factors such as mobility, traffic density, forwarding techniques and method of junction selection mechanism, and strategy used to handle a local optimum situation. It also provides the simulation based study of existing dynamic junction selection routing protocols and a static junction selection routing protocol. It provides a profound insight into the routing techniques suggested in this area and the most valuable solutions to advance VANETs. More importantly, it can be used as a source of references to other researchers in finding literature that is relevant to routing in VANETs.

  14. Reliable Freestanding Position-Based Routing in Highway Scenarios

    Science.gov (United States)

    Galaviz-Mosqueda, Gabriel A.; Aquino-Santos, Raúl; Villarreal-Reyes, Salvador; Rivera-Rodríguez, Raúl; Villaseñor-González, Luis; Edwards, Arthur

    2012-01-01

    Vehicular Ad Hoc Networks (VANETs) are considered by car manufacturers and the research community as the enabling technology to radically improve the safety, efficiency and comfort of everyday driving. However, before VANET technology can fulfill all its expected potential, several difficulties must be addressed. One key issue arising when working with VANETs is the complexity of the networking protocols compared to those used by traditional infrastructure networks. Therefore, proper design of the routing strategy becomes a main issue for the effective deployment of VANETs. In this paper, a reliable freestanding position-based routing algorithm (FPBR) for highway scenarios is proposed. For this scenario, several important issues such as the high mobility of vehicles and the propagation conditions may affect the performance of the routing strategy. These constraints have only been partially addressed in previous proposals. In contrast, the design approach used for developing FPBR considered the constraints imposed by a highway scenario and implements mechanisms to overcome them. FPBR performance is compared to one of the leading protocols for highway scenarios. Performance metrics show that FPBR yields similar results when considering freespace propagation conditions, and outperforms the leading protocol when considering a realistic highway path loss model. PMID:23202159

  15. Static Three-Dimensional Fuzzy Routing Based on the Receiving Probability in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sohrab Khanmohammadi

    2013-11-01

    Full Text Available A Wireless Sensor Network (WSN is a collection of low-cost, low-power and large-scale wireless sensor nodes. Routing protocols are an important topic in WSN. Every sensor node should use a proper mechanism to transmit the generated packets to its destination, usually a base station. In previous works, routing protocols use the global information of the network that causes the redundant packets to be increased. Moreover, it leads to an increase in the network traffic, to a decrease in the delivery ratio of data packets, and to a reduction in network life. In this paper, we propose a new inferential routing protocol called SFRRP (Static Three-Dimensional Fuzzy Routing based on the Receiving Probability. The proposed protocol solves the above mentioned problems considerably. The data packets are transmitted by hop-to-hop delivery to the base station. It uses a fuzzy procedure to transmit the sensed data or the buffered data packets to one of the neighbors called selected node. In the proposed fuzzy system, the distance and number of neighbors are input variables, while the receiving probability is the output variable. SFRRP just uses the local neighborhood information to forward the packets and is not needed by any redundant packet for route discovery. The proposed protocol has some advantages such as a high delivery ratio, less delay time, high network life, and less network traffic. The performance of the proposed protocol surpasses the performance of the Flooding routing protocol in terms of delivery ratio, delay time and network lifetime.

  16. Study protocol

    DEFF Research Database (Denmark)

    Smith, Benjamin E; Hendrick, Paul; Bateman, Marcus

    2017-01-01

    avoidance behaviours, catastrophising, self-efficacy, sport and leisure activity participation, and general quality of life. Follow-up will be 3 and 6 months. The analysis will focus on descriptive statistics and confidence intervals. The qualitative components will follow a thematic analysis approach....... DISCUSSION: This study will evaluate the feasibility of running a definitive large-scale trial on patients with patellofemoral pain, within the NHS in the UK. We will identify strengths and weaknesses of the proposed protocol and the utility and characteristics of the outcome measures. The results from...... this study will inform the design of a multicentre trial. TRIAL REGISTRATION: ISRCTN35272486....

  17. On-demand generation of background-free single photons from a solid-state source

    Science.gov (United States)

    Schweickert, Lucas; Jöns, Klaus D.; Zeuner, Katharina D.; Covre da Silva, Saimon Filipe; Huang, Huiying; Lettner, Thomas; Reindl, Marcus; Zichi, Julien; Trotta, Rinaldo; Rastelli, Armando; Zwiller, Val

    2018-02-01

    True on-demand high-repetition-rate single-photon sources are highly sought after for quantum information processing applications. However, any coherently driven two-level quantum system suffers from a finite re-excitation probability under pulsed excitation, causing undesirable multi-photon emission. Here, we present a solid-state source of on-demand single photons yielding a raw second-order coherence of g(2 )(0 )=(7.5 ±1.6 )×10-5 without any background subtraction or data processing. To this date, this is the lowest value of g(2 )(0 ) reported for any single-photon source even compared to the previously reported best background subtracted values. We achieve this result on GaAs/AlGaAs quantum dots embedded in a low-Q planar cavity by employing (i) a two-photon excitation process and (ii) a filtering and detection setup featuring two superconducting single-photon detectors with ultralow dark-count rates of (0.0056 ±0.0007 ) s-1 and (0.017 ±0.001 ) s-1, respectively. Re-excitation processes are dramatically suppressed by (i), while (ii) removes false coincidences resulting in a negligibly low noise floor.

  18. Pain treatment after tonsillectomy: advantages of analgesics regularly given compared with analgesics on demand.

    Science.gov (United States)

    Thorneman, G; Akervall, J

    2000-10-01

    The aim of the present prospective study was to evaluate pain treatment during the first postoperative 24 h for 40 patients (age over 18) undergoing tonsillectomy. Patients were divided into two groups: group A (n = 20) received analgesics on demand and group B (n = 20) on a regular basis. Basic pain treatment consisted of paracetamol 750 mg x 6 and diclofenac 50 mg x 3. Pain measurement was performed using a visual analogue scale (VAS): a 10 cm line with 0 cm equalling no pain and 10 cm equalling the worst pain ever felt. The following parameters were studied: VAS values, the need for rescue analgesics, intra- and postoperative bleeding, nausea and vomiting, postoperative food intake and hospital time. Only 4 of 20 (20%) patients in group B needed rescue analgesics in the postoperative ward compared with 15 of 20 (75%) in group A (p values were generally rather low in both groups. The mean value for all observed VAS values was less than 4 in both study groups. However, no significant difference in VAS values was observed between the two study groups. Our results suggest that regularly given postoperative pain treatment after tonsillectomy, starting intraoperatively with paracetamol and diclofenac, has significant advantages compared with a regimen in which patients receive analgesics only on demand.

  19. Novel dynamic caching for hierarchically distributed video-on-demand systems

    Science.gov (United States)

    Ogo, Kenta; Matsuda, Chikashi; Nishimura, Kazutoshi

    1998-02-01

    It is difficult to simultaneously serve the millions of video streams that will be needed in the age of 'Mega-Media' networks by using only one high-performance server. To distribute the service load, caching servers should be location near users. However, in previously proposed caching mechanisms, the grade of service depends on whether the data is already cached at a caching server. To make the caching servers transparent to the users, the ability to randomly access the large volume of data stored in the central server should be supported, and the operational functions of the provided service should not be narrowly restricted. We propose a mechanism for constructing a video-stream-caching server that is transparent to the users and that will always support all special playback functions for all available programs to all the contents with a latency of only 1 or 2 seconds. This mechanism uses Variable-sized-quantum-segment- caching technique derived from an analysis of the historical usage log data generated by a line-on-demand-type service experiment and based on the basic techniques used by a time- slot-based multiple-stream video-on-demand server.

  20. On-Demand Targeting: Investigating Biology with Proximity-Directed Chemistry.

    Science.gov (United States)

    Long, Marcus J C; Poganik, Jesse R; Aye, Yimon

    2016-03-23

    Proximity enhancement is a central chemical tenet underpinning an exciting suite of small-molecule toolsets that have allowed us to unravel many biological complexities. The leitmotif of this opus is "tethering"-a strategy in which a multifunctional small molecule serves as a template to bring proteins/biomolecules together. Scaffolding approaches have been powerfully applied to control diverse biological outcomes such as protein-protein association, protein stability, activity, and improve imaging capabilities. A new twist on this strategy has recently appeared, in which the small-molecule probe is engineered to unleash controlled amounts of reactive chemical signals within the microenvironment of a target protein. Modification of a specific target elicits a precisely timed and spatially controlled gain-of-function (or dominant loss-of-function) signaling response. Presented herein is a unique personal outlook conceptualizing the powerful proximity-enhanced chemical biology toolsets into two paradigms: "multifunctional scaffolding" versus "on-demand targeting". By addressing the latest advances and challenges in the established yet constantly evolving multifunctional scaffolding strategies as well as in the emerging on-demand precision targeting (and related) systems, this Perspective is aimed at choosing when it is best to employ each of the two strategies, with an emphasis toward further promoting novel applications and discoveries stemming from these innovative chemical biology platforms.

  1. Control Scheme Formulation for the Production of Hydrogen on Demand to Feed an Internal Combustion Engine

    Directory of Open Access Journals (Sweden)

    Jarniel García Morales

    2016-12-01

    Full Text Available In this work, a control strategy is presented to produce hydrogen on demand to feed an internal combustion (IC engine. For this purpose, the modeling of the IC engine fueled by gasoline blended with 10 % v/v of anhydrous ethanol (E10 and hydrogen as an additive is developed. It is considered that the hydrogen gas is produced according to the IC engine demand, and that the hydrogen gas is obtained by an alkaline electrolyzer. The gasoline–ethanol blend added into the combustion chamber is determined according to the stoichiometric ratio and the production of hydrogen gas is regulated by a proportional and integral controller (P.I.. The controller reference is varying according to the mass flow air induced into the cylinder, in order to ensure an adequate production of hydrogen gas for any operating condition of the IC engine. The main contribution of this work is the control scheme developed, through simulation, in order to produce hydrogen on demand for any operating point of an internal combustion engine fueled by an E10 blend. The simulation results showed that the use of hydrogen gas as an additive in an E10 blend decreases the E10 fuel consumption 23 % on average, and the thermal efficiency is increased approximately 2.13 % , without brake power loss in the IC engine.

  2. Fast-responsive hydrogel as an injectable pump for rapid on-demand fluidic flow control.

    Science.gov (United States)

    Luo, Rongcong; Dinh, Ngoc-Duy; Chen, Chia-Hung

    2017-05-01

    Chemically synthesized functional hydrogels have been recognized as optimized soft pumps for on-demand fluidic regulation in micro-systems. However, the challenges regarding the slow responses of hydrogels have very much limited their application in effective fluidic flow control. In this study, a heterobifunctional crosslinker (4-hydroxybutyl acrylate)-enabled two-step hydrothermal phase separation process for preparing a highly porous hydrogel with fast response dynamics was investigated for the fabrication of novel microfluidic functional units, such as injectable valves and pumps. The cylinder-shaped hydrogel, with a diameter of 9 cm and a height of 2.5 cm at 25 °C, achieved a size reduction of approximately 70% in less than 30 s after the hydrogels were heated at 40 °C. By incorporating polypyrrole nanoparticles as photothermal transducers, a photo-responsive composite hydrogel was approached and exhibited a remotely triggerable fluidic regulation and pumping ability to generate significant flows, showing on-demand water-in-oil droplet generation by laser switching, whereby the droplet size could be tuned by adjusting the laser intensity and irradiation period with programmable manipulation.

  3. Versatile and on-demand biologics co-production in yeast.

    Science.gov (United States)

    Cao, Jicong; Perez-Pinera, Pablo; Lowenhaupt, Ky; Wu, Ming-Ru; Purcell, Oliver; de la Fuente-Nunez, Cesar; Lu, Timothy K

    2018-01-08

    Current limitations to on-demand drug manufacturing can be addressed by technologies that streamline manufacturing processes. Combining the production of two or more drugs into a single batch could not only be useful for research, clinical studies, and urgent therapies but also effective when combination therapies are needed or where resources are scarce. Here we propose strategies to concurrently produce multiple biologics from yeast in single batches by multiplexing strain development, cell culture, separation, and purification. We demonstrate proof-of-concept for three biologics co-production strategies: (i) inducible expression of multiple biologics and control over the ratio between biologic drugs produced together; (ii) consolidated bioprocessing; and (iii) co-expression and co-purification of a mixture of two monoclonal antibodies. We then use these basic strategies to produce drug mixtures as well as to separate drugs. These strategies offer a diverse array of options for on-demand, flexible, low-cost, and decentralized biomanufacturing applications without the need for specialized equipment.

  4. Road Routes for Waste Disposal - MDC_RecyclingRoute

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — This CURBSIDE RECYCLING ROUTES BOUNDARIES LAYER IS A polygon feature class created for the Miami-Dade Department of Solid Waste Management (DSWM). It contains the...

  5. Capacity Constrained Routing Algorithms for Evacuation Route Planning

    National Research Council Canada - National Science Library

    Lu, Qingsong; George, Betsy; Shekhar, Shashi

    2006-01-01

    .... In this paper, we propose a new approach, namely a capacity constrained routing planner which models capacity as a time series and generalizes shortest path algorithms to incorporate capacity constraints...

  6. Pheromone based alternative route planning

    Directory of Open Access Journals (Sweden)

    Liangbing Feng

    2016-08-01

    Full Text Available In this work, we propose an improved alternative route calculation based on alternative figures, which is suitable for practical environments. The improvement is based on the fact that the main traffic route is the road network skeleton in a city. Our approach using nodes may generate a higher possibility of overlapping. We employ a bidirectional Dijkstra algorithm to search the route. To measure the quality of an Alternative Figures (AG, three quotas are proposed. The experiment results indicate that the improved algorithm proposed in this paper is more effective than others.

  7. Route planning algorithms: Planific@ Project

    Directory of Open Access Journals (Sweden)

    Gonzalo Martín Ortega

    2009-12-01

    Full Text Available Planific@ is a route planning project for the city of Madrid (Spain. Its main aim is to develop an intelligence system capable of routing people from one place in the city to any other using the public transport. In order to do this, it is necessary to take into account such things as: time, traffic, user preferences, etc. Before beginning to design the project is necessary to make a comprehensive study of the variety of main known route planning algorithms suitable to be used in this project.

  8. Port Authority of Allegheny County Transit Routes

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Shapefile of Transit Routes - Please refer to each resource for active dates of the route information. Routes change over time,

  9. VT Route Log Points 2017

    Data.gov (United States)

    Vermont Center for Geographic Information — This data layer is used with VTrans' Integrated Route Log System (IRA). It is also used to calibrate the linear referencing systems, including the End-to-End and...

  10. Characteristics of on-demand biogas production by using sugar beet silage.

    Science.gov (United States)

    Ahmed, Sharif; Kazda, Marian

    2017-08-01

    On-demand electricity generation can be achieved by just-in-time biogas production instantly utilized in co-generation units. For this goal, easily degradable substrates like sugar beet silage have a high potential. Potential for on-demand biogas production from co-digestion of sugar beet silage (SS) with grass silage (GS) was evaluated in two experiments at organic loading rates (OLRs) of 1.5 kgVS m -3 day -1 and 2.5 kgVS m -3 day -1 , respectively. Each experiment was fed with intermittent feeding system at 8 hrs interval at the same feedstock ratios (volatile solids based) of GS:SS-1:0, 3:1 and 1:3, respectively. Modelling by Gaussian equation was performed in order to understand the effects of SS on biogas production. Addition of sugar beet silage led to maximum biogas production within a short time, but it differed significantly depending on feedstock ratios and OLRs, respectively. At OLR 1.5 kgVS m -3 day -1 , during mono fermentation of grass silage maximum biogas production rate of 0.27 l N hr -1 was reached at 2.74 hrs. Production rate did not change at feedstock ratio of GS:SS-3:1 but increased to 0.64 l N hr -1 at GS:SS-1:3 within a shorter time span (1.58 hrs). On the contrary, at OLR of 2.5 kgVS m -3 day -1 time span between feedstock input and maximum biogas production did not differ significantly (p > 0.05) among the reactors. Biogas production rates were 0.60 l N hr -1 within 2.27 hrs and 0.82 l N hr -1 within 2.30 hrs at GS:SS-3:1 and GS:SS-1:3, respectively. Surprisingly, there was no time lag between maximum biogas and methane production rates, irrespectively of OLR. This implies that once the whole microbial community is adapted to intermittent substrate input, the metabolic products are instantly utilized through the all steps of anaerobic substrate degradation. Applying this finding opens new perspectives for on-demand biogas energy production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. New TPG bus route 28

    CERN Multimedia

    2003-01-01

    Geneva's Public Transport services (TPG) have recently inaugurated a new bus line 28, connecting the La Tour Hospital in Meyrin to the international organisations in Geneva, via the airport. All signs associated with this route will be yellow in colour. Timetables and route details can be found at http://www.tpg.ch. Relations with the Host States Service http://www.cern.ch/relations/ Tel. 72848

  12. Beyond protocols

    DEFF Research Database (Denmark)

    Vanderhoeven, Sonia; Branquart, Etienne; Casaer, Jim

    2017-01-01

    Risk assessment tools for listing invasive alien species need to incorporate all available evidence and expertise. Beyond the wealth of protocols developed to date, we argue that the current way of performing risk analysis has several shortcomings. In particular, lack of data on ecological impact...... information on risk and the exploration of improved methods for decision making on biodiversity management. This is crucial for efficient conservation resource allocation and uptake by stakeholders and the public......., transparency and repeatability of assessments as well as the incorporation of uncertainty should all be explicitly considered. We recommend improved quality control of risk assessments through formalized peer review with clear feedback between assessors and reviewers. Alternatively, a consensus building...

  13. Exploring the Feasibility of Reputation Models for Improving P2P Routing under Churn

    Science.gov (United States)

    Sànchez-Artigas, Marc; García-López, Pedro; Herrera, Blas

    Reputation mechanisms help peer-to-peer (P2P) networks to detect and avoid unreliable or uncooperative peers. Recently, it has been discussed that routing protocols can be improved by conditioning routing decisions to the past behavior of forwarding peers. However, churn — the continuous process of node arrival and departure — may severely hinder the applicability of rating mechanisms. In particular, short lifetimes mean that reputations are often generated from a small number of transactions.

  14. On joint power allocation and multipath routing in femto-relay networks

    OpenAIRE

    Hoteit , Sahar; Duhamel , Pierre; Lasaulce , Samson

    2016-01-01

    International audience; —Transmit power allocation techniques are very important to manage interference in small-cell networks. While available power allocation algorithms in the literature rely on a predefined routing protocol, we propose in this paper a power-efficient two-step algorithm that allows power allocation and routing to be performed jointly in femto-relay networks. First, we propose an interference-based partitioning method to cluster the femto-relays, then we adopt an iterative ...

  15. Label-based routing for a family of scale-free, modular, planar and unclustered graphs

    International Nuclear Information System (INIS)

    Comellas, Francesc; Miralles, Alicia

    2011-01-01

    We give an optimal labeling and routing algorithm for a family of scale-free, modular and planar graphs with zero clustering. The relevant properties of this family match those of some networks associated with technological and biological systems with a low clustering, including some electronic circuits and protein networks. The existence of an efficient routing protocol for this graph model should help when designing communication algorithms in real networks and also in the understanding of their dynamic processes.

  16. Proposal of interference reduction routing for ad-hoc networks

    Directory of Open Access Journals (Sweden)

    Katsuhiro Naito

    2010-10-01

    Full Text Available In this paper, we propose an interference reduction routing protocol for ad-hoc networks. The interference is one of the degradation factors in wireless communications. In the ad-hoc network, some nodes communicate simultaneously. Therefore, these communications cause interference each other, and some packets are corrupted due to interference from another node. In the proposed protocol, each node estimates required transmission power according to hello messages. Therefore, the node can transmit a data packet with minimum required transmission power. Consequently, the interference against neighbor nodes can be reduced. From simulation results, we can find that the proposed protocol can reduce the number of control messages and can improve the throughput performance.

  17. Auction-Based Cloud Service Pricing and Penalty with Availability on Demand

    Directory of Open Access Journals (Sweden)

    Xiaohong Wu

    2018-04-01

    Full Text Available Availability is one of the main concerns of cloud users, and cloud providers always try to provide higher availability to improve user satisfaction. However, higher availability results in higher provider costs and lower social welfare. In this paper, taking into account both the users’ valuation and desired availability, we design resource allocation, pricing and penalty mechanisms with availability on demand. Considering two scenarios: public availability in which the desired availabilities of all users are public information, and private availability in which the desired availabilities are private information of users, and, analyzing the possible behaviours of users, we design a truthful deterministic mechanism with 2-approximation in public availability scenario and a universal truthful mechanism with 1 1 + γ approximation in private availability scenario, where γ is the backup ratio of resources with the highest availability. The experiment results show that our mechanisms significantly improve the social welfare compared to the mechanism without considering availability demand of users.

  18. Distribution of Video-on-Demand Service over Cable Television Networks

    Directory of Open Access Journals (Sweden)

    L. T. Jordanova

    2009-06-01

    Full Text Available The paper deals with investigations carried out to increase the effectiveness of video-on-demand (VoD systems when cable television networks are used. A comparative analysis of the existing VoD architectures is made with respect to the equipment cost and the traffic load over the central transport network. Through statistical studies the main characteristics of a particular hybrid VoD are determined (such as twenty-four-hour distribution of the video traffic, average inter-arrival time of the VoD requests, average duration of video streams demanded, movies distribution according to the subscribers’ preferences. An algorithm for the videocontent flexible distribution among the distribution hubs is suggested. Thus a higher effectiveness of the system is achieved without significantly increasing the equipment cost.

  19. Eliminating LH2 in LOX-collect space launchers - Key to on-demand capability

    Science.gov (United States)

    Leingang, J. L.; Carreiro, L. R.; Maurice, L. Q.

    1993-01-01

    Two air-breathing reusable two-stage space launch vehicle concepts are proposed, in which the first stage employs turboramjet propulsion and the second stage uses rockets, which are expected to provide very rapid response launch of 10,000 lb polar-orbit payloads. In both concepts, liquid oxygen (LOX) for the second stage is collected during first stage ascent, thus eliminating the need for LOX ground servicing facilities. In the first concept, liquid hydrogen in the amount just sufficient to condense and collect second state LOX is the only cryogenic fluid that is loaded on the vehicle at takeoff. The second concept uses the heat sink of conventional jet propulsion fuel and water coolant to drive a lightweight adaptation of the commercial LOX production process, eliminating all cryogenics at takeoff. Both concepts should permit true launch-on-demand capability with aircraftlike ground operations.

  20. Storage and on-demand release of microwaves using superconducting resonators with tunable coupling

    International Nuclear Information System (INIS)

    Pierre, Mathieu; Svensson, Ida-Maria; Raman Sathyamoorthy, Sankar; Johansson, Göran; Delsing, Per

    2014-01-01

    We present a system which allows to tune the coupling between a superconducting resonator and a transmission line. This storage resonator is addressed through a second, coupling resonator, which is frequency-tunable and controlled by a magnetic flux applied to a superconducting quantum interference device. We experimentally demonstrate that the lifetime of the storage resonator can be tuned by more than three orders of magnitude. A field can be stored for 18 μs when the coupling resonator is tuned off resonance and it can be released in 14 ns when the coupling resonator is tuned on resonance. The device allows capture, storage, and on-demand release of microwaves at a tunable rate.

  1. On-Demand Micro-Power Generation from an Origami-Inspired Paper Biobattery Stack

    Directory of Open Access Journals (Sweden)

    Maedeh Mohammadifar

    2018-03-01

    Full Text Available We use origami to create a compact, scalable three-dimensional (3-D biobattery stack that delivers on-demand energy to the portable biosensors. Folding allows a two-dimensional (2-D paper sheet possessing predefined functional components to form nine 3-D microbial fuel cells (MFCs, and connect them serially within a small and single unit (5.6 cm × 5.6 cm. We load the biocatalyst Pseudomonas aeruginosa PAO1 in predefined areas that form the MFCs, and freeze-dry them for long-term storage. The biobattery stack generates a maximum power and current of 20 μW and 25 μA, respectively, via microbial metabolism when the freeze-dried cells are rehydrated with readily available wastewater. This work establishes an innovative strategy to revolutionize the fabrication, storage, operation, and application of paper-based MFCs, which could potentially make energy available even in resource-limited settings.

  2. Orthogonal Clickable Iron Oxide Nanoparticle Platform for Targeting, Imaging, and On-Demand Release.

    Science.gov (United States)

    Guldris, Noelia; Gallo, Juan; García-Hevia, Lorena; Rivas, José; Bañobre-López, Manuel; Salonen, Laura M

    2018-04-12

    A versatile iron oxide nanoparticle platform is reported that can be orthogonally functionalized to obtain highly derivatized nanomaterials required for a wide variety of applications, such as drug delivery, targeted therapy, or imaging. Facile functionalization of the nanoparticles with two ligands containing isocyanate moieties allows for high coverage of the surface with maleimide and alkyne groups. As a proof-of-principle, the nanoparticles were subsequently functionalized with a fluorophore as a drug model and with biotin as a targeting ligand towards tumor cells through Diels-Alder and azide-alkyne cycloaddition reactions, respectively. The thermoreversibility of the Diels-Alder product was exploited to induce the on-demand release of the loaded molecules by magnetic hyperthermia. Additionally, the nanoparticles were shown to target cancer cells through in vitro experiments, as analyzed by magnetic resonance imaging. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Origami-inspired, on-demand deployable and collapsible mechanical metamaterials with tunable stiffness

    Science.gov (United States)

    Zhai, Zirui; Wang, Yong; Jiang, Hanqing

    2018-03-01

    Origami has been employed to build deployable mechanical metamaterials through folding and unfolding along the crease lines. Deployable metamaterials are usually flexible, particularly along their deploying and collapsing directions, which unfortunately in many cases leads to an unstable deployed state, i.e., small perturbations may collapse the structure along the same deployment path. Here we create an origami-inspired mechanical metamaterial with on-demand deployability and selective collapsibility through energy analysis. This metamaterial has autonomous deployability from the collapsed state and can be selectively collapsed along two different paths, embodying low stiffness for one path and substantially high stiffness for another path. The created mechanical metamaterial yields load-bearing capability in the deployed direction while possessing great deployability and collapsibility. The principle in this work can be utilized to design and create versatile origami-inspired mechanical metamaterials that can find many applications.

  4. On-demand semiconductor source of 780-nm single photons with controlled temporal wave packets

    Science.gov (United States)

    Béguin, Lucas; Jahn, Jan-Philipp; Wolters, Janik; Reindl, Marcus; Huo, Yongheng; Trotta, Rinaldo; Rastelli, Armando; Ding, Fei; Schmidt, Oliver G.; Treutlein, Philipp; Warburton, Richard J.

    2018-05-01

    We report on a fast, bandwidth-tunable single-photon source based on an epitaxial GaAs quantum dot. Exploiting spontaneous spin-flip Raman transitions, single photons at 780 nm are generated on demand with tailored temporal profiles of durations exceeding the intrinsic quantum dot lifetime by up to three orders of magnitude. Second-order correlation measurements show a low multiphoton emission probability [g2(0 ) ˜0.10 -0.15 ] at a generation rate up to 10 MHz. We observe Raman photons with linewidths as low as 200 MHz, which is narrow compared to the 1.1-GHz linewidth measured in resonance fluorescence. The generation of such narrow-band single photons with controlled temporal shapes at the rubidium wavelength is a crucial step towards the development of an optimized hybrid semiconductor-atom interface.

  5. Reversible, on-demand generation of aqueous two-phase microdroplets

    Science.gov (United States)

    Collier, Charles Patrick; Retterer, Scott Thomas; Boreyko, Jonathan Barton; Mruetusatorn, Prachya

    2017-08-15

    The present invention provides methods of on-demand, reversible generation of aqueous two-phase microdroplets core-shell microbeads, microparticle preparations comprising the core-shell microbeads, and drug delivery formulation comprising the microparticle preparations. Because these aqueous microdroplets have volumes comparable to those of cells, they provide an approach to mimicking the dynamic microcompartmentation of biomaterial that naturally occurs within the cytoplasm of cells. Hence, the present methods generate femtoliter aqueous two-phase droplets within a microfluidic oil channel using gated pressure pulses to generate individual, stationary two-phase microdroplets with a well-defined time zero for carrying out controlled and sequential phase transformations over time. Reversible phase transitions between single-phase, two-phase, and core-shell microbead states are obtained via evaporation-induced dehydration and water rehydration.

  6. Drop-on-Demand Sample Delivery for Studying Biocatalysts in Action at XFELs

    Science.gov (United States)

    Fuller, Franklin D.; Gul, Sheraz; Chatterjee, Ruchira; Burgie, Ernest S.; Young, Iris D.; Lebrette, Hugo; Srinivas, Vivek; Brewster, Aaron S.; Michels-Clark, Tara; Clinger, Jonathan A.; Andi, Babak; Ibrahim, Mohamed; Pastor, Ernest; de Lichtenberg, Casper; Hussein, Rana; Pollock, Christopher J.; Zhang, Miao; Stan, Claudiu A.; Kroll, Thomas; Fransson, Thomas; Weninger, Clemens; Kubin, Markus; Aller, Pierre; Lassalle, Louise; Bräuer, Philipp; Miller, Mitchell D.; Amin, Muhamed; Koroidov, Sergey; Roessler, Christian G.; Allaire, Marc; Sierra, Raymond G.; Docker, Peter T.; Glownia, James M.; Nelson, Silke; Koglin, Jason E.; Zhu, Diling; Chollet, Matthieu; Song, Sanghoon; Lemke, Henrik; Liang, Mengning; Sokaras, Dimosthenis; Alonso-Mori, Roberto; Zouni, Athina; Messinger, Johannes; Bergmann, Uwe; Boal, Amie K.; Bollinger, J. Martin; Krebs, Carsten; Högbom, Martin; Phillips, George N.; Vierstra, Richard D.; Sauter, Nicholas K.; Orville, Allen M.; Kern, Jan; Yachandra, Vittal K.; Yano, Junko

    2017-01-01

    X-ray crystallography at X-ray free-electron laser (XFEL) sources is a powerful method for studying macromolecules at biologically relevant temperatures. Moreover, when combined with complementary techniques like X-ray emission spectroscopy (XES), both global structures and chemical properties of metalloenzymes can be obtained concurrently, providing new insights into the interplay between the protein structure/dynamics and chemistry at an active site. Implementing such a multimodal approach can be compromised by conflicting requirements to optimize each individual method. In particular, the method used for sample delivery greatly impacts the data quality. We present here a new, robust way of delivering controlled sample amounts on demand using acoustic droplet ejection coupled with a conveyor belt drive that is optimized for crystallography and spectroscopy measurements of photochemical and chemical reactions over a wide range of time scales. Studies with photosystem II, the phytochrome photoreceptor, and ribonucleotide reductase R2 illustrate the power and versatility of this method. PMID:28250468

  7. Interim report by a Committee on Demands and Supplies of Electric Enterprise Council

    International Nuclear Information System (INIS)

    1984-01-01

    An interim report by a committee on demands and supplies, Electric Enterprise Council, was given for the period up to the year 2000. The demands of electric power in Japan were set as 658,000 million kWh for 1990 and 768,000 million kWh for 1995. The electric power enterprises appear to be at a major turning point at present, that is, the growth in the demands tended to slow down. The features of the situation are then the stabilized supply, supply cost reduction, reasonable power source constitution, etc. The following things are described. Background and policy; power demand outlook and supply measures; power supply and supply efficiency (the composition of power sources, respective power sources with supply targets and problems, etc.); power demand/supply outlook for 2000. (Mori, K.)

  8. Symmetry Breaking in Photonic Crystals: On-Demand Dispersion from Flatband to Dirac Cones.

    Science.gov (United States)

    Nguyen, H S; Dubois, F; Deschamps, T; Cueff, S; Pardon, A; Leclercq, J-L; Seassal, C; Letartre, X; Viktorovitch, P

    2018-02-09

    We demonstrate that symmetry breaking opens a new degree of freedom to tailor energy-momentum dispersion in photonic crystals. Using a general theoretical framework in two illustrative practical structures, we show that breaking symmetry enables an on-demand tuning of the local density of states of the same photonic band from zero (Dirac cone dispersion) to infinity (flatband dispersion), as well as any constant density over an adjustable spectral range. As a proof of concept, we demonstrate experimentally the transformation of the very same photonic band from a conventional quadratic shape to a Dirac dispersion, a flatband dispersion, and a multivalley one. This transition is achieved by finely tuning the vertical symmetry breaking of the photonic structures. Our results provide an unprecedented degree of freedom for optical dispersion engineering in planar integrated photonic devices.

  9. Stimuli-Responsive NO Release for On-Demand Gas-Sensitized Synergistic Cancer Therapy.

    Science.gov (United States)

    Fan, Wenpei; Yung, Bryant C; Chen, Xiaoyuan

    2018-03-08

    Featuring high biocompatibility, the emerging field of gas therapy has attracted extensive attention in the medical and scientific communities. Currently, considerable research has focused on the gasotransmitter nitric oxide (NO) owing to its unparalleled dual roles in directly killing cancer cells at high concentrations and cooperatively sensitizing cancer cells to other treatments for synergistic therapy. Of particular note, recent state-of-the-art studies have turned our attention to the chemical design of various endogenous/exogenous stimuli-responsive NO-releasing nanomedicines and their biomedical applications for on-demand NO-sensitized synergistic cancer therapy, which are discussed in this Minireview. Moreover, the potential challenges regarding NO gas therapy are also described, aiming to advance the development of NO nanomedicines as well as usher in new frontiers in this fertile research area. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Ethics consultation on demand: concepts, practical experiences and a case study.

    Science.gov (United States)

    Reiter-Theil, S

    2000-06-01

    Despite the increasing interest in clinical ethics, ethics consultation as a professional service is still rare in Europe. In this paper I refer to examples in the United States. In Germany, university hospitals and medical faculties are still hesitant about establishing yet another "committee". One of the reasons for this hesitation lies in the ignorance that exists here about how to provide medical ethics services; another reason is that medical ethics itself is not yet institutionalised at many German universities. The most important obstacle, however, may be that medical ethics has not yet demonstrated its relevance to the needs of those caring for patients. The Centre for Ethics and Law, Freiburg, has therefore taken a different approach from that offered elsewhere: clinical ethics consultation is offered on demand, the consultation being available to clinician(s) in different forms. This paper describes our experiences with this approach; practical issues are illustrated by a case study.

  11. An Opportunistic Wireless Charging System Design for an On-Demand Shuttle Service: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Doubleday, Kate; Meintz, Andrew; Markel, Tony

    2016-08-01

    System right-sizing is critical to implementation of in-motion wireless power transfer (WPT) for electric vehicles. This study introduces a modeling tool, WPTSim, which uses one-second speed, location, and road grade data from an on-demand employee shuttle in operation to simulate the incorporation of WPT at fine granularity. Vehicle power and state of charge are simulated over the drive cycle to evaluate potential system designs. The required battery capacity is determined based on the rated power at a variable number of charging locations. Adding just one WPT location can more than halve the battery capacity needed. Many configurations are capable of being self sustaining with WPT, while others benefit from supplemental stationary charging.

  12. Automated Metadata Formatting for Cornell’s Print-on-Demand Books

    Directory of Open Access Journals (Sweden)

    Dianne Dietrich

    2009-11-01

    Full Text Available Cornell University Library has made Print-On Demand (POD books available for many of its digitized out-of-copyright books. The printer must be supplied with metadata from the MARC bibliographic record in order to produce book covers. Although the names of authors are present in MARC records, they are given in an inverted order suitable for alphabetical filing rather than the natural order that is desirable for book covers. This article discusses a process for parsing and manipulating the MARC author strings to identify their various component parts and to create natural order strings. In particular, the article focuses on processing non-name information in author strings, such as titles that were commonly used in older works, e.g., baron or earl, and suffixes appended to names, e.g., "of Bolsena." Relevant patterns are identified and a Python script is used to manipulate the author name strings.

  13. On-demand single-photon state generation via nonlinear absorption

    International Nuclear Information System (INIS)

    Hong Tao; Jack, Michael W.; Yamashita, Makoto

    2004-01-01

    We propose a method for producing on-demand single-photon states based on collision-induced exchanges of photons and unbalanced linear absorption between two single-mode light fields. These two effects result in an effective nonlinear absorption of photons in one of the modes, which can lead to single-photon states. A quantum nonlinear attenuator based on such a mechanism can absorb photons in a normal input light pulse and terminate the absorption at a single-photon state. Because the output light pulses containing single photons preserve the properties of the input pulses, we expect this method to be a means for building a highly controllable single-photon source

  14. An organic fluorophore-nanodiamond hybrid sensor for photostable imaging and orthogonal, on-demand biosensing.

    Science.gov (United States)

    Purdey, Malcolm S; Capon, Patrick K; Pullen, Benjamin J; Reineck, Philipp; Schwarz, Nisha; Psaltis, Peter J; Nicholls, Stephen J; Gibson, Brant C; Abell, Andrew D

    2017-11-21

    Organic fluorescent probes are widely used to detect key biomolecules; however, they often lack the photostability required for extended intracellular imaging. Here we report a new hybrid nanomaterial (peroxynanosensor, PNS), consisting of an organic fluorescent probe bound to a nanodiamond, that overcomes this limitation to allow concurrent and extended cell-based imaging of the nanodiamond and ratiometric detection of hydrogen peroxide. Far-red fluorescence of the nanodiamond offers continuous monitoring without photobleaching, while the green fluorescence of the organic fluorescent probe attached to the nanodiamond surface detects hydrogen peroxide on demand. PNS detects basal production of hydrogen peroxide within M1 polarised macrophages and does not affect macrophage growth during prolonged co-incubation. This nanosensor can be used for extended bio-imaging not previously possible with an organic fluorescent probe, and is spectrally compatible with both Hoechst 33342 and MitoTracker Orange stains for hyperspectral imaging.

  15. New Class of Hybrid Materials for Detection, Capture, and "On-Demand" Release of Carbon Monoxide.

    Science.gov (United States)

    Pitto-Barry, Anaïs; Lupan, Alexandru; Ellingford, Christopher; Attia, Amr A A; Barry, Nicolas P E

    2018-04-25

    Carbon monoxide (CO) is both a substance hazardous to health and a side product of a number of industrial processes, such as methanol steam reforming and large-scale oxidation reactions. The separation of CO from nitrogen (N 2 ) in industrial processes is considered to be difficult because of the similarities of their electronic structures, sizes, and physicochemical properties (e.g., boiling points). Carbon monoxide is also a major poison in fuel cells because of its adsorption onto the active sites of the catalysts. It is therefore of the utmost economic importance to discover new materials that enable effective CO capture and release under mild conditions. However, methods to specifically absorb and easily release CO in the presence of contaminants, such as water, nitrogen, carbon dioxide, and oxygen, at ambient temperature are not available. Here, we report the simple and versatile fabrication of a new class of hybrid materials that allows capture and release of carbon monoxide under mild conditions. We found that carborane-containing metal complexes encapsulated in networks made of poly(dimethylsiloxane) react with CO, even when immersed in water, leading to dramatic color and infrared signature changes. Furthermore, we found that the CO can be easily released from the materials by simply dipping the networks into an organic solvent for less than 1 min, at ambient temperature and pressure, which not only offers a straightforward recycling method, but also a new method for the "on-demand" release of carbon monoxide. We illustrated the utilization of the on-demand release of CO from the networks by carrying out a carbonylation reaction on an electron-deficient metal complex that led to the formation of the CO-adduct, with concomitant recycling of the gel. We anticipate that our sponge-like materials and scalable methodology will open up new avenues for the storage, transport, and controlled release of CO, the silent killer and a major industrial poison.

  16. A Novel Software Platform Extending Advances in Monitoring Technologies to On-demand Decision Support

    Science.gov (United States)

    Ormerod, R.; Scholl, M.

    2017-12-01

    Rapid evolution is occurring in the monitoring and assessment of air emissions and their impacts. The development of next generation lower cost sensor technologies creates the potential for much more intensive and far-reaching monitoring networks that provide spatially rich data. While much attention at present is being directed at the types and performance characteristics of sensor technologies, it is important also that the full potential of rich data sources be realized. Parallel to sensor developments, software platforms to display and manage data in real time are increasingly common adjuncts to sensor networks. However, the full value of data can be realized by extending platform capabilities to include complex scientific functions that are integrated into an action-oriented management framework. Depending on the purpose and nature of a monitoring network, there will be a variety of potential uses of the data or its derivatives, for example: statistical analysis for policy development, event analysis, real-time issue management including emergency response and complaints, and predictive management. Moving these functions into an on-demand, optionally mobile, environment greatly increases the value and accessibility of the data. Increased interplay between monitoring data and decision-making in an operational environment is optimised by a system that is designed with equal weight on technical robustness and user experience. A system now being used by several regulatory agencies and a larger number of industries in the US, Latin America, Europe, Australia and Asia has been developed to provide a wide range of on-demand decision-support in addition to the basic data collection, display and management that most platforms offer. With stable multi-year operation, the platform, known as Envirosuite, is assisting organisations to both reduce operating costs and improve environmental performance. Some current examples of its application across a range of applications

  17. On-demand calibration and evaluation for electromagnetically tracked laparoscope in augmented reality visualization.

    Science.gov (United States)

    Liu, Xinyang; Plishker, William; Zaki, George; Kang, Sukryool; Kane, Timothy D; Shekhar, Raj

    2016-06-01

    Common camera calibration methods employed in current laparoscopic augmented reality systems require the acquisition of multiple images of an entire checkerboard pattern from various poses. This lengthy procedure prevents performing laparoscope calibration in the operating room (OR). The purpose of this work was to develop a fast calibration method for electromagnetically (EM) tracked laparoscopes, such that the calibration can be performed in the OR on demand. We designed a mechanical tracking mount to uniquely and snugly position an EM sensor to an appropriate location on a conventional laparoscope. A tool named fCalib was developed to calibrate intrinsic camera parameters, distortion coefficients, and extrinsic parameters (transformation between the scope lens coordinate system and the EM sensor coordinate system) using a single image that shows an arbitrary portion of a special target pattern. For quick evaluation of calibration results in the OR, we integrated a tube phantom with fCalib prototype and overlaid a virtual representation of the tube on the live video scene. We compared spatial target registration error between the common OpenCV method and the fCalib method in a laboratory setting. In addition, we compared the calibration re-projection error between the EM tracking-based fCalib and the optical tracking-based fCalib in a clinical setting. Our results suggest that the proposed method is comparable to the OpenCV method. However, changing the environment, e.g., inserting or removing surgical tools, might affect re-projection accuracy for the EM tracking-based approach. Computational time of the fCalib method averaged 14.0 s (range 3.5 s-22.7 s). We developed and validated a prototype for fast calibration and evaluation of EM tracked conventional (forward viewing) laparoscopes. The calibration method achieved acceptable accuracy and was relatively fast and easy to be performed in the OR on demand.

  18. Efficacy and treatment satisfaction with on-demand tadalafil (Cialis) in men with erectile dysfunction.

    Science.gov (United States)

    Skoumal, René; Chen, Juza; Kula, Krzysztof; Breza, Jan; Calomfirescu, Nicolae; Basson, Bruce R; Kopernicky, Vladimir

    2004-09-01

    Tadalafil (Cialis) is an inhibitor of phosphodiesterase type 5, which mediates relaxation of vascular smooth muscle in the corpus cavernosum thus facilitating erection. The purpose of this multicentre, randomized, double-blind, parallel group, placebo-controlled study was to evaluate efficacy and treatment satisfaction of on-demand Cialis in men with mild-to-severe erectile dysfunction (ED). Following a 4-week treatment-free run in period, patients stratified into three severity groups by the International Index of Erectile Function (IIEF) Erectile Function (EF) domain score were randomized to receive either placebo or Cialis 20 mg taken on demand over a 12-week period. Efficacy endpoints were change from baseline in IIEF EF domain scores, responses to Sexual Encounter Profile diary (SEP) questions, and responses to the Global Assessment Questions (GAQ). Treatment satisfaction was evaluated using the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) questionnaire in two of seven participating countries where validated translations were available. Of the 443 men who entered the trial, 409 (mean age, 52 years) formed the intent-to-treat population. Mean baseline demographics and ED severity measures were balanced between treatment groups except for a higher percentage of patients naïve to sildenafil in the tadalafil group compared to placebo (50% versus 36%). The percentage of patients in each IIEF EF severity class (mild, moderate and severe) was 47%, 30% and 23% for placebo patients and 48%, 29% and 23% for tadalafil patients, respectively. Tadalafil was significantly superior to placebo on all primary efficacy measures (IIEF EF domain scores, SEP15, GAQ1; p satisfaction relative to placebo, and is well tolerated. This is the first study to yield efficacy data on tadalafil in an Eastern European population of men with erectile dysfunction, and the first to measure satisfaction with the EDITS questionnaire in any study population of men with this

  19. On-demand Simulation of Atmospheric Transport Processes on the AlpEnDAC Cloud

    Science.gov (United States)

    Hachinger, S.; Harsch, C.; Meyer-Arnek, J.; Frank, A.; Heller, H.; Giemsa, E.

    2016-12-01

    The "Alpine Environmental Data Analysis Centre" (AlpEnDAC) develops a data-analysis platform for high-altitude research facilities within the "Virtual Alpine Observatory" project (VAO). This platform, with its web portal, will support use cases going much beyond data management: On user request, the data are augmented with "on-demand" simulation results, such as air-parcel trajectories for tracing down the source of pollutants when they appear in high concentration. The respective back-end mechanism uses the Compute Cloud of the Leibniz Supercomputing Centre (LRZ) to transparently calculate results requested by the user, as far as they have not yet been stored in AlpEnDAC. The queuing-system operation model common in supercomputing is replaced by a model in which Virtual Machines (VMs) on the cloud are automatically created/destroyed, providing the necessary computing power immediately on demand. From a security point of view, this allows to perform simulations in a sandbox defined by the VM configuration, without direct access to a computing cluster. Within few minutes, the user receives conveniently visualized results. The AlpEnDAC infrastructure is distributed among two participating institutes [front-end at German Aerospace Centre (DLR), simulation back-end at LRZ], requiring an efficient mechanism for synchronization of measured and augmented data. We discuss our iRODS-based solution for these data-management tasks as well as the general AlpEnDAC framework. Our cloud-based offerings aim at making scientific computing for our users much more convenient and flexible than it has been, and to allow scientists without a broad background in scientific computing to benefit from complex numerical simulations.

  20. Optimization of mine ventilation fan speeds according to ventilation on demand and time of use tariff

    International Nuclear Information System (INIS)

    Chatterjee, Arnab; Zhang, Lijun; Xia, Xiaohua

    2015-01-01

    Highlights: • DSM techniques are applied to an underground mine ventilation network. • A minimization model is solved to find the optimal speeds of the main mine fan. • Ventilation on demand (VOD) leads to a saving of USD 213160. • The optimal mining schedule, together with VOD, leads to a saving of USD 277035. • According to a case study, a maximum of 2 540 035 kW h can be saved per year. - Abstract: In the current situation of the energy crisis, the mining industry has been identified as a promising area for application of demand side management (DSM) techniques. This paper investigates the potential for energy-cost savings and actual energy savings, by implementation of variable speed drives to ventilation fans in underground mines. In particular, ventilation on demand is considered in the study, i.e., air volume is adjusted according to the demand at varying times. Two DSM strategies, energy efficiency (EE) and load management (LM), are formulated and analysed. By modelling the network with the aid of Kirchhoff’s laws and Tellegen’s theorem, a nonlinear constrained minimization model is developed, with the objective of achieving EE. The model is also made to adhere to the fan laws, such that the fan power at its operating points is found to achieve realistic results. LM is achieved by finding the optimal starting time of the mining schedule, according to the time of use (TOU) tariff. A case study is shown to demonstrate the effects of the optimization model. The study suggests that by combining load shifting and energy efficiency techniques, an annual energy saving of 2 540 035 kW h is possible, leading to an annual cost saving of USD 277035