Now-a-days, mobile ad-hoc network is growing tremendously. Establishment of communication between nodes is very hectic and required task. A primary requirement for the establishment of communication among nodes in mobile ad hoc network (MANETs) is that nodes cooperate with one another. This requirement may raise serious security concerns in the presence of malicious node; for example, such nodes may disrupt the routing process. Preventing or detecting malicious nodes launching gray-hole or collaborative black hole attacks is a challenge in the context. This paper attempts to address this issue by developing the cooperative bait detection scheme, a dynamic source routing mechanism that combines the benefits of both proactive and reactive defense architectures. To help achieve the stated goal, our CBDS method employs a reverse tracing technique. In our proposed work black-hole nodes are detected and removed from communication path, with the help of CBDS algorithm. CBDS algorithm detects node with the Bait RREQ and RREP messages.

Dynamic Source Routing (DSR), Cooperative Bait Detection Scheme (CBDS), RREQ, RREP, Bait RREQ.