Date Added: Feb 2013
Sensor nodes are usually deployed in an open environment therefore they are subjected to various kinds of attacks like Worm Hole attack, Black Hole attack, False Data Injection attacks. Since the attackers can cause disruption and failure to the network, it's very important to detect these compromised nodes and revoke them before any major disruption occurs. Therefore, it's very important to safe guard the network from further disruption. For this purpose a method called Biased SPRT (Sequential Probability Ratio Test) is used by setting up some Threshold Value and Trust Aggregator in the network scenario for which the network is divided into number of Zones.