Topological Comparison Based Approach of Detecting Wormhole Attacks in OLSR Protocol

MANETs are vulnerable to a number of security threats due to their flexible characteristics such as dynamic topology formation, openness of the wireless medium and resource constraints. Wormhole attack is one of the most sophisticated forms of security threats in MANET wherein two or more colluders silently record packets at one location and then tunnel them to another location in the network. As a result, two distant nodes believe that there exists a direct communication link between them. In this paper, we focus on the wormhole attack problem in optimized link state routing (OLSR) protocol. We propose to conduct both round trip time (RTT) measurement and topological comparison to detect wormhole attack. Simulation results show that our proposed method can achieve high detection rate and accuracy of alarms.