Witness-Based Detection of Forwarding Misbehaviors in Wireless Networks

We consider the problem of identifying a node that incorrectly forwards packets in a static wireless ad hoc network. We propose a detection scheme that identifies a misbehaving node based on observations made by neighboring nodes (witnesses) near the forwarding node. Without longterm or cumulative observation, the proposed scheme makes an instantaneous decision about whether a node is correctly forwarding a packet. Through extensive analysis under various threat scenarios, we show that our scheme can unambiguously identify a misbehaving node when there is no collusion. We analyze our scheme's detection accuracy accounting for the lossy nature of wireless links, finding that our scheme can achieve high detection accuracy while incurring low communication overhead.