2,989 research outputs found

    On the Throughput-Delay Trade-off in Georouting Networks

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    We study the scaling properties of a georouting scheme in a wireless multi-hop network of nn mobile nodes. Our aim is to increase the network capacity quasi linearly with nn while keeping the average delay bounded. In our model, mobile nodes move according to an i.i.d. random walk with velocity vv and transmit packets to randomly chosen destinations. The average packet delivery delay of our scheme is of order 1/v1/v and it achieves the network capacity of order nlognloglogn\frac{n}{\log n\log\log n}. This shows a practical throughput-delay trade-off, in particular when compared with the seminal result of Gupta and Kumar which shows network capacity of order n/logn\sqrt{n/\log n} and negligible delay and the groundbreaking result of Grossglausser and Tse which achieves network capacity of order nn but with an average delay of order n/v\sqrt{n}/v. We confirm the generality of our analytical results using simulations under various interference models.Comment: This work has been submitted to IEEE INFOCOM 201

    Stability of secure routing protocol in ad hoc wireless network.

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    The contributions of this research are threefold. First, it offers a new routing approach to ad hoc wireless network protocols: the Enhanced Heading-direction Angle Routing Protocol (EHARP), which is an enhancement of HARP based on an on-demand routing scheme. We have added important features to overcome its disadvantages and improve its performance, providing the stability and availability required to guarantee the selection of the best path. Each node in the network is able to classify its neighbouring nodes according to their heading directions into four different zone-direction group. The second contribution is to present a new Secure Enhanced Heading-direction Angle Routing Protocol (SEHARP) for ad hoc networks based on the integration of security mechanisms that could be applied to the EHARP routing protocol. Thirdly, we present a new approach to security of access in hostile environments based on the history and relationships among the nodes and on digital operation certificates. We also propose an access activity diagram which explains the steps taken by a node. Security depends on access to the history of each unit, which is used to calculate the cooperative values of each node in the environment

    Routing and mobility strategies for mobile ad hoc networks

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    EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    A hierarchical detection method in external communication for self-driving vehicles based on TDMA

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    Security is considered a major challenge for self-driving and semi self-driving vehicles. These vehicles depend heavily on communications to predict and sense their external environment used in their motion. They use a type of ad hoc network termed Vehicular ad hoc networks (VANETs). Unfortunately, VANETs are potentially exposed to many attacks on network and application level. This paper, proposes a new intrusion detection system to protect the communication system of self-driving cars; utilising a combination of hierarchical models based on clusters and log parameters. This security system is designed to detect Sybil and Wormhole attacks in highway usage scenarios. It is based on clusters, utilising Time Division Multiple Access (TDMA) to overcome some of the obstacles of VANETs such as high density, high mobility and bandwidth limitations in exchanging messages. This makes the security system more efficient, accurate and capable of real time detection and quick in identification of malicious behaviour in VANETs. In this scheme, each vehicle log calculates and stores different parameter values after receiving the cooperative awareness messages from nearby vehicles. The vehicles exchange their log data and determine the difference between the parameters, which is utilised to detect Sybil attacks and Wormhole attacks. In order to realize efficient and effective intrusion detection system, we use the well-known network simulator (ns-2) to verify the performance of the security system. Simulation results indicate that the security system can achieve high detection rates and effectively detect anomalies with low rate of false alarms
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