A decentralize incentive mechanism for P2P file sharing systems

As experience with P2P networks shows, the selfish behaviors of peers may lead to free-riding and tragedy of common. Most of the existing work is concerning probabilistic estimation to build reputation system to evaluate the triistwor- thiness for a peer to others. However, they can fail with positive probability and also suffer from long-term interaction. In this paper, we design a multiple-principal multiple-agent model that can provide incentives to peers in P2P file sharing networks in a way of Vickrey-Clarke-Groves mechanism, while assuming every peer in P2P networks is rational and selfish, which means they only concern about their own outcome. This mechanism has some desirable properties: incentive compatibility, individual rationality, and full decentralization. The implementation of our mechanism is complemented by a decentralized accounting scheme which provides accountability for applications in a secure and scalable way. Simulation experiments are performed to provide evidence of the mechanism´s efficiency and reliability even in the presence of faulty or malicious peers.