Sequential detection of misbehaving nodes in cooperative networks with HARQ

Existing cooperative communications protocols are designed with the assumption that users always behave in a socially efficient manner. This assumption may be valid in networks under the control of a single authority where nodes cooperate efficiently to achieve a common goal. On the other hand, in commercial wireless networks where nodes are individually motivated to cooperate, the assumption that nodes will always obey rules of cooperation may not hold without implementing a mechanism to detect and mitigate misbehavior. In this paper, we present a sequential misbehavior technique based on sequential probability ratio test (SPRT) for cooperative networks using automatic repeat request (ARQ). We evaluate performance of the detection technique both analytically and using numerical methods.