Attacks and countermeasures on routing protocols in wireless networks

Routing in wireless networks is not an easy task as they are highly vulnerable to attacks. The main goal of this work is to study the routing performance and security aspects of wireless ad hoc and mesh networks. Most of the routing protocols use hop-count as the routing metric. Hop count metric may not be appropriate for routing in wireless networks as this does not account for the link qualities, advantages of multi-radio paradigm etc. There are several metrics designed for link quality based source routing protocols for multi-radio wireless ad hoc and mesh networks. For example Weighted Cumulative Expected Transmission Time (WCETT), Adjusted Expected Transfer Delay(AETD) etc. But these metrics do not consider the effect of individual link qualities on the total route quality and route selection. This lack of ability from WCETT or AETD would allow them to select suboptimal paths when actually an optimal path is available. In another point of view, this inability can create a routing disruption attack named as delay-variation attack (a variant of black hole attack). It can be launched by a couple of colluding attackers attracting packets at one point by showing very good link qualities and dropping packets at another point by decreasing the link quality. To select an optimal route and prevent the above mentioned attack, a new routing metric known as Variance Based Path Quality metric (VBPQ) is proposed. VBPQ metric provides a robust, reliable and secure edge to the routing mechanism.;Another major contribution of this study is to provide a detection mechanism for wormhole attacks in wireless ad hoc networks operating on link quality based source routing protocols. There have been several detection techniques designed for hop count based routing protocols but not for link quality based source routing protocols. In this work, a data mining approach called Cross feature analysis is used in an algorithm to detect wormhole attacks.