Abstract: Mobile Adhoc Network gain much attention because of its uses in various critical areas such as military exercises, Disaster recovery, Mine site operations, etc. As mobile nodes in MANET are autonomous nodes, each mobile node assist their neighbor nodes for packet forwarding towards intended destination. The cooperation among the mobile nodes ensures the reliable communication in MANET. Some mobile nodes refuse to forward the packet from other nodes due to lack of resources or malicious activity. This kind of nodes is called as selfish nodes. The presence of selfish nodes in the route degrades the overall performance of the network. So, this paper aims to review the various selfish node detection mechanisms. The unique features are inspected and the constraints are discussed.

Keywords: Mobile Adhoc network, Selfish nodes, Malicious, Cooperative communication.