Recovery based Time Synchronization for Wireless Networks

Time synchronization schemes in Wireless Sensor Networks have been subjected to various security threats and attacks. In this paper we throw light on some of these attacks. Nevertheless we are more concerned with the pulse delay attack which cannot be countered using any of the cryptographic techniques. We propose an algorithm called Resync algorithm which not only detects the delay attack but also aims to rectify the compromised node and introduce it back in the network for the synchronization process. In-depth analysis has been done in terms of the rate of success achieved in detecting multiple outliers i.e. nodes under attack and the level of accuracy obtained in the offset values after running the Resync algorithm.