PTT: Packet Travel Time Algorithm in Mobile Ad Hoc Networks

The wormhole attack is hard to detect and can be easily implemented. An attacker may receive packets from one location in the network and tunnel them to the other end point in a different location and re-inject them into the network. Attackers can tunnel the packets by one of the following methods: encapsulating the packets, using out-of-bound links or using high power. If there are two or more malicious nodes in the network involved in a wormhole attack, the attack becomes more powerful. There are two types of wormhole attacks: hidden mode, and exposed (participation) mode. In this paper, we present an algorithm for detecting wormhole attacks, whether in hidden or exposed mode in wireless multi-hop net-works without special hardware. Our algorithm is an improvement on another algorithm which is based on transmission time-based mechanism (TTM). Moreover, our algorithm introduces a new mechanism called Packet Travel Time (PTT). This mechanism allows each device to monitor its neighbours´ behaviour. Therefore, this mechanism can detect both hidden and exposed wormhole attacks, and can locate the wormhole in AODV, and DSR protocol.