A novel encounter based trust evaluation for AODV routing in MANET

Several routing protocols in MANET have been proposed which emphasize on optimal route discovery without considering security. Several trust metrics have been proposed for trust calculation such as packet forwarding rate, receiving rate, packet misrouted and so on. However, they only show their efficiency in static scenarios. To deal with the mobility factor, an attempt has been made to find a suitable trust metric besides the existing trust metrics. This paper introduces `average encounter rate´ as one of the trust metric based on the concept of `Encounter´. We propose a trust based routing protocol named AER-AODV protocol which evaluates direct trust with average encounter rate (AER) and successful cooperation frequency. Indirect trust is evaluated using the revised D-S evidence theory. Simulation results show that AER-AODV can isolate the malicious nodes effectively when building the route. In addition, it achieves better performance than AODV and TAODV in terms of throughput and packet delivery ratio.