Abstract
Security is important factor for several sensor network applications. Wireless sensor Networks (WSN) when deployed in hostile environments as static or mobile, an antagonist will try to physically capture some of the nodes, once a node is captured, it collects all the credentials like keys and identity etc. the attacker will re-program it and repeat the node so as to form replicas and listen the transmitted messages or adjust the functionality of the network. Identity felony ends up in 2 sorts attack: clone and Sybil. In particularly a catastrophic attack against sensor networks wherever one or more node(s) illegitimately claims an identity as replicas is known as the node replication attack. The replication attack is tremendously injurious to many important functions of the sensor network like routing, resource allocation, mis-behavior detection, etc. This paper inspect the threat posed by the replication attack and a number of other novel techniques to find and preserve adjacent to t