Trust-based minimum cost opportunistic routing for Ad hoc networks

Recently, opportunistic routing has received much attention as a new design direction. It can exploit the wireless broadcast and more highly reliable opportunistic forwarding, so as to substantially increase the throughput of network. Due to dynamic topology, distributed collaboration, limited bandwidth and computing ability, the absence of enough physical protection in Ad hoc networks, opportunistic routing is vulnerable to attacks by malicious nodes. In order to alleviate the malicious behaviors, we incorporate the concept of trust to Ad hoc networks, build a simple trust model to evaluate neighbors' forwarding behavior and apply this model to opportunistic routing for Ad hoc networks. A new trusted opportunistic forwarding model is proposed by choosing the trusted and highest priority candidate forwarder, then a trusted minimum cost routing algorithm (MCOR) is formally formulated, the correctness and effectiveness of this algorithm from theoretical analysis are also approved. Finally, MCOR algorithm is verified by simulation using nsclick software and compared its performance with the classic protocols: ExOR,TAODV and Watchdog-DSR. The simulation results show that MCOR scheme can detect and mitigate node misbehaviors. Furthermore, MCOR scheme outperforms the other protocols in terms of: throughput, delay, Expected ETX, security-gains and cost of routing. Crown Copyright (C) 2011 Published by Elsevier Inc. All rights reserved.