Deploying trust gateways to reinforce dynamic source routing

A mobile ad-hoc network comprises of a number of low power wireless nodes. Each of these participating nodes endeavours to pass packets for other nodes based upon a preagreed protocol. The dynamic source routing (DSR) protocol is one of the most commonly used protocols in ad-hoc wireless networks. In a DSR based network, each transmitted data packet contains the complete list of node addresses that the packet has to traverse in order to reach its final destination. Intermediate nodes blindly forward these packets as per the attached list without taking into consideration the behavioural pattern of the subsequent nodes. In this paper, we present a variant of the DSR protocol in which intermediary nodes act as trust gateways. These gateways take into account the contemporary trust levels of the network nodes and thus facilitate in detecting and evading malicious nodes. With the help of extensive simulations, we demonstrate that the proposed DSR protocol augments the performance of the standard DSR protocol by up to 30% in a network where 40% of the nodes act maliciously. The proposed scheme is also independent of cryptographic mechanisms and does not impose any superfluous conditions upon the network establishment and operation phase.