The initial need to setup the communication of nodes in mobile adhoc network [MANETs] is that all the nodes should act together..In the Manets environment if any malevolent nodes are present in the obligation it may escort to grave attacks such as Black Hole and Grey Hole attack. Such nodes may Disrupt the Routing Process. Identifying and Prventing of attacks like Black Hole or the Gray Hole attack in network communication is the main challenge. In this context our paper is attempt to identify and preventing the malicious node using Cooperative bait Detection Scheme [CBDS] approach which is Dynamic source routing based [DSR] mechanism and place them into the black hole list and broadcast the alert message over the network. CBDS approach combines the benifit of both Proactive and Reactive Defence mechanism.

Keywords : Mobileadhoc network[MANETs], CBDS, DSR, Malevolent nodes, Black hole attack, Grey hole attack.