Abstract: Mobile Ad-hoc Network (MANET) is infrastructure less and central object less network in which the mobile nodes can communicate using wireless links. Due to this, Network is vulnerable to many attacks. This paper focuses on selfish behaviour and different countermeasures available. Nodes may deny participating in the routing process for its own benefits like to save battery, storage space, bandwidth etc. Various policies like token based, credit based, reputation based, trust based etc. are used to detect and prevent selfishness.

Keywords: Network Security, MANET, Selfish attack, countermeasures, wireless security.