A secure credit-based cooperation stimulating mechanism for MANETs using hash chains

One of the most challenging problems in self-organized mobile ad hoc networks (MANETs), which consist of autonomous and self-interested nodes, is to stimulate the nodes to cooperate in routing and packet forwarding. In this paper, we propose a novel credit-based cooperation mechanism that utilizes hash chains on messages to defend against cheating by the nodes. We show that it imposes a low workload on the nodes in comparison with the mechanisms that deploy digital signature schemes. Moreover, through a game-theoretic analysis, it is shown that any level of cooperation by a node will be attainable if the mechanism makes appropriate payments.