Trust Based Multi Path DSR Protocol

Abstract

Ad-hoc networks establish communication in improvised environments without requiring any fixed infrastructure. These networks are inherently prone to security attacks, with node mobility being the primary cause in allowing security breaches. Therefore secure routing is a must for such networks. A number of secure routing protocols based on trust have recently been proposed. However, all these protocols use the traditional route discovery model, where a node drops RREQ packet if its own ID is in the source route of the packet, or if it has previously processed the packet. A misbehaving node takes advantage of this vulnerability and forwards the RREQ fast, so that the RREQ received from other nodes are dropped and the path discovered includes itself (the misbehaving node). In this paper, we present a unique trust based method which is not vulnerable to this behavior. In our method, each node broadcasts a RREQ packet if it is received from different neighbors. A secure and efficient route to the destination is calculated as a weighted average of the trust value of the nodes in the route, with respect to its behavior observed by its neighboring nodes and the number of nodes in the route. We evaluate the misbehaving node detection rate and the efficiency of our method along a number of parameters. Results show that our method increases the throughput of the network while discovering a secure route.