MOSAODV: Solution to Secure AODV against Blackhole Attack

Mobile ad hoc network (popularly known as MANET) showing promising applications have now gained significant importance in research as well as in practice, due to their autonomous and self-maintaining nature. Unlike other types of networks, MANETs are usually deployed without a centralized control unit. Hence, mutual cooperation amongst the participating entities forms the basis for determining the routes to the destination. This aspect along with the fact that MANET nodes are often constrained in power, storage and computational resources, make MANETs vulnerable to various communications security related attacks. Therefore, the direc t application of the conventional routing algorithms is infeasible here. Numerous attempts can be found in the literature that concentrates on improving the security of the routing protocols for MANETS. However, according to our analysis, none of them is complete by itself. In this paper, therefore, we focus on improving the Secure Adhoc On demand Distance Vector (AODV) routing protocol to safeguard it against a Denial of Service attack viz. the Blackhole attack. The proposed modifications to AODV are implemented and tested using Network Simulator (NS-2.33). The performance analysis carried out shows improvement in Packet Delivery Ratio of AODV in presence of Blackhole attack, with marginal rise in average end-to-end delay and normalized routing overhead.