Enhancing security of zone-based routing protocol using trust

Ad hoc networks are formed with the help of their constituent wireless mobile nodes which are expected to forward packets for other nodes in a cooperative manner. Zone Routing Protocol; ZRP is one of such protocols that helps to create and maintain routes in spite of the dynamic network topology. This protocol is vulnerable to a number of security threats that come from internal malicious nodes which have authorization credentials to participate in the network. Malicious nodes deliberately drop data packets and disrupt the correct operation of the routing protocol. This paper proposes a security enhancement of ZRP based on trust calculations. The performance of a defenseless ZRP when a number of network´s nodes misbehave and drop data packets is evaluated. Then the impact of proposed enhancement is evaluated and compared to the performance of the defenseless ZRP. The simulation results indicate that the presence of malicious nodes is a significant problem to the defenseless ZRP protocol and that the proposed protocol improves the packet delivery ratio, but the cost of this improvement is the increase in end to end delay and routing overhead.