19,663 research outputs found

    Node Cooperation in Hybrid Ad hoc Networks

    Get PDF
    A hybrid ad hoc network is a structure-based network that is extended using multi-hop communications. Indeed, in this kind of network, the existence of a communication link between the mobile station and the base station is not required: A mobile station that has no direct connection with a base station can use other mobile stations as relays. Compared with conventional (single-hop) structure-based networks, this new generation can lead to a better use of the available spectrum and to a reduction of infrastructure costs. However, these benefits would vanish if the mobile nodes did not properly cooperate and forward packets for other nodes. In this paper, we propose a charging and rewarding scheme to encourage the most fundamental operation, namely packet forwarding. We use ``MAC layering" to reduce the space overhead in the packets and a stream cipher encryption mechanism to provide ``implicit authentication" of the nodes involved in the communication. We analyze the robustness of our protocols against rational and malicious attacks. We show that - using our solution - collaboration is rational for selfish nodes. We also show that our protocols thwart rational attacks and detect malicious attacks

    Survey on Quality Analysis of Collaboration Motivation Approach in Wireless Ad Hoc Networks

    Get PDF
    In Wireless Ad Hoc Networks (WANETs), tasks are conducted based on the cooperation of nodes in the networks. However, since the nodes are usually constrained by limited computation resources, selfish nodes may refuse to be cooperative. Reputation system is one of the main solutions to the node non cooperation problem. A reputation system evaluates node behaviours by reputation values and uses a reputation threshold to distinguish trustworthy nodes and untrustworthy nodes. Although this system has been widely used, very little research has been devoted to investigating the effectiveness of the node cooperation incentives provided by the systems. We propose a protocol called Enhanced Reverse Ad Hoc On Demand Vector Routing Protocol (ERAODV), which uses Hybrid Reputation System (HRS). A Hybrid Reputation system is an enhanced version of Classical Reputation System (CRS). Unlike the CRS it takes into account all the reputation values from the node to determine whether it is trustworthy or not. Keywords: WANET; Reputation System; Price Based System; Quality Analysis; Multipath Routing

    Mac layer misbehaviors in mobile ad hoc networks

    Get PDF
    MAC misbehavior in mobile ad hoc networks (MANET) is relatively new and unexplored in the literature. Different from traditional wireline networks, the unique nature of MANETs has opened new challenges in the network design. An Mobile Ad Hoc Network (MANET) is a collection of wireless mobile hosts forming a temporary network without the aid of any established infrastructure or centralized administration. In such an environment, one mobile host may need the aid of other hosts to communicate with the destination. However, failed data transmission due to selfish or malicious or hybrid node misbehavior and faulty nodes can severely degrade the overall network performance. Hence, a well-behaved node needs to adaptively change its cooperation level to cope with node misbehavior. In this thesis, we first briefly overview the existing security issues in ad hoc network routing and MAC layers. We explain security methods such as economic incentives, secure routing by cryptography and detection system against greedy behavior alleviate some of the problems, but not all

    Fuzzy Logic Based DSR Trust Estimation Routing Protocol for MANET Using Evolutionary Algorithms

    Get PDF
    In MANET attaining consistent routing is a main problem due to several reasons such as lack of static infrastructure, exposed transmission medium, energetic network topology and restricted battery power. These features also create the scheme of direction-finding protocols in MANETs become even more interesting. In this work, a Trust centered routing protocol is suggested, since trust plays a vital role in computing path in mobile ad hoc networks (MANETs). Estimating and computing trust encourages cooperation in mobile ad hoc networks (MANETs). Various present grade systems suddenly estimate the trust by considering any one of the parameters such as energy of node, number of hops and mobility. Estimating trust is an Energetic multi objective optimization problem (EMOPs) typically including many contradictory goals such as lifetime of node, lifetime of link and buffer occupancy proportion which change over time. To solve this multi objective problem, a hybrid Harmony Search Combined with Genetic algorithm and Cuckoo search is used along with reactive method Dynamic Source routing protocol to provide the mobile hosts to find out and sustain routes between the origin node (SN) to the target node (TN). In this work, the performance of the direction-finding practice is assessed using throughput, end to end delay, and load on the network and route detection period

    RECOMAC: a cross-layer cooperative network protocol for wireless ad hoc networks

    Get PDF
    A novel decentralized cross-layer multi-hop cooperative protocol, namely, Routing Enabled Cooperative Medium Access Control (RECOMAC) is proposed for wireless ad hoc networks. The protocol architecture makes use of cooperative forwarding methods, in which coded packets are forwarded via opportunistically formed cooperative sets within a region, as RECOMAC spans the physical, medium access control (MAC) and routing layers. Randomized coding is exploited at the physical layer to realize cooperative transmissions, and cooperative forwarding is implemented for routing functionality, which is submerged into the MAC layer, while the overhead for MAC and route set up is minimized. RECOMAC is shown to provide dramatic performance improvements of eight times higher throughput and one tenth of end-to-end delay than that of the conventional architecture in practical wireless mesh networks
    corecore