Time synchronization attacks in sensor networks

Time synchronization is a critical building block in distributed wireless sensor networks. Because sensor nodes may be severely resource-constrained, traditional time-synchronization protocols cannot be used in sensor networks. Various time-synchronization protocols tailored for such networks have been proposed to solve this problem. However, none of these protocols have been designed with security in mind. If an adversary were able to compromise a node, he might prevent a network from effectively executing certain applications, such as sensing or tracking an object, or he might even disable the network by disrupting a fundamental service such as a TDMA-based channel-sharing scheme. In this paper we give a survey of the most common time synchronization protocols and outline the possible attacks on each protocol. In addition, we discuss how different sensor network applications that are affected by time synchronization attacks, and we propose some countermeasures for these attack.