A game theory based reputation mechanism to incentivize cooperation in wireless ad hoc networks

In wireless ad hoc networks one way to incentivize nodes to forward other nodes’ packets is through the use of reputation mechanisms, where cooperation is induced by the threat of partial or total network disconnection if a node acts selfishly. The problem is that packet collisions and interference may make cooperative nodes appear selfish sometimes, generating unnecessary and unwanted punishments. With the use of a simple network model we first study the performance of some proposed reputation strategies and then present a new mechanism called DARWIN (Distributed and Adaptive Reputation mechanism for Wireless ad hoc Networks), where we try to avoid retaliation situations after a node is falsely perceived as selfish to help restore cooperation quickly. Using game theory, we prove that our mechanism is robust to imperfect measurements, is collusion-resistant and can achieve full cooperation among nodes. Simulations are presented to complement our theoretical analysis and evaluate the performance of our algorithm compared to other proposed reputation strategies.