Intrusion Detection for Black Hole and Gray Hole in MANETs

Black and gray hole attack is one kind of routing disturbing attacks and can bring great damage to the network. As a result, an efficient algorithm to detect black and gray attack is itnportant. This paper de1nonstrate an adaptive approach to detecting black and gray hole attacks in ad hoc network based on a cross layer design. In network layer, we proposed a path-based 1nethod to overhear the next hop's action. This scheme does not send out extra control packets and saves the syste1n resources of the detecting node. In MAC layer, a collision rate reporting system is established to estimate dynamic detecting threshold so as to lov.1er the false positive rate under high network overload. We choose DSR protocol to test our algorithm and ns-2 as our simulation tool. Our experiment result verifies our theo1y: the average detection rate is above 90% and the fa lse positive rate is be low I 0%. Moreover, the adaptive threshold strategy contributes to decrease the false positive rate.