Date Added: Mar 2012
Wireless Sensor Networks are vulnerable because nodes are often placed in a hostile or dangerous environment, where they are not physically protected. A central problem in sensor network security is that sensors are susceptible to physical node capture attacks. Once a sensor is compromised, the adversary can easily launch replica attacks by duplicating the compromised node, distributing the replicas throughout the network and starting a variety of insider attacks. Previous works against replica attacks suffer from a high communication/storage overhead or poor detection accuracy. A new protocol called Node Location Maintenance (NLM) protocol is used. This employs a table of values at each node to record the trace of the random walks.