Game Theory Analysis for Graded Punishment Mechanism Restraining Free-Riding in P2P Networks

In recent years, various selfish behaviors of P2P network nodes have become increasingly severe, and the existence of free-riding, white-washing and the like deteriorates the performance of systems. This paper addresses the free-riding problem in P2P networks, and proposes a novel three-grade-punishment mechanism to restrain free-riding conducts in terms of game theory and reputation management to promote the mutual cooperation. The Nash Equilibrium is proved to be available for the rational nodes with this mechanism in a P2P system. The simulation results indicate that the proposed graded punishment mechanism is effective in restraining free-riding behaviors and improving cooperation between nodes.