New efficient mechanisms to secure OLSR protocol

Securing routing protocols in ad hoc networks is a very complex and still topical domain due to the binding characteristics of these networks, and their high vulnerability to attacks. OLSR is among the most used proactive routing protocols. Several secure extensions have been proposed to deal with its security, but they often involve a very high resource consumption that degrades network performances. The protocol ADVSIG is one of these extensions. It presents an efficient security approach, but generates very high computational costs due to the cryptographic operations it performs on the control messages. In this paper, we present a secure mechanism for OLSR, based on ADVSIG protocol, that we call HCA_OLSR. Its purpose is to improve ADVSIG performances using hash chains to reduce the cost of securing HELLO control messages. A watching mechanism is also proposed to counter the wormhole attack. The whole solution is simulated and analyzed using NS2.