A Collusion-Resistant Routing Scheme for Noncooperative Wireless Ad Hoc Networks

In wireless ad hoc networks, routing needs cooperation of nodes. Since nodes often belong to different users, it is highly important to provide incentives for them to cooperate. However, most existing studies of the incentive-compatible routing problem focus on individual nodes' incentives, assuming that no subset of them would collude. Clearly, this assumption is not always valid. In this paper, we present a systematic study of collusion-resistant routing in noncooperative wireless ad hoc networks. In particular, we consider two standard solution concepts for collusion resistance in game theory, namely Group Strategyproofness and Strong Nash Equilibrium. We show that achieving Group Strategyproofness is impossible, while achieving Strong Nash Equilibrium is possible. More specifically, we design a scheme that is guaranteed to converge to a Strong Nash Equilibrium and prove that the total payment needed is bounded. In addition, we propose a cryptographic method that prevents profit transfer among colluding nodes, as long as they do not fully trust each other unconditionally. This method makes our scheme widely applicable in practice. Experiments show that our solution is collusion-resistant and has good performance.