Enhance the Security of AODV Routing Protocol forMobile Ad Hoc Networks

Abstract

Mobile ad hoc network is an infrastructureless wireless network and is formed by a group of mobile wireless nodes which cooperatively communicate with each other using wireless technology. The features of ad-hoc networks are rapid deployment and low cost operation. Because of the broadcast nature of radio and secure weaknesses of the routing protocols, ad-hoc networks are usually susceptible to different security threats. In this study, we proposed a scheme to enhance the Ad-hoc On-Demand Distance Vector (AODV) routing protocol. We adopted two mechanisms to secure the AODV message. One mechanism used digital signatures to protect the non-mutable fields of the messages, and another mechanism applied hash chains to secure the only mutable information in the messages (hop count information). Besides, we added a seed value to digital signature to prevent that malicious nodes reuse the same digital signature, and in order to protect the data packets to be transmitted, source node and destination node must exchange each other’s seed and then use these two seeds to derive a session key, which is to be used to encrypt and decrypt data packet. The performance of the proposed security mechanisms was evaluated by using NCTU-ns network simulator.