A Novel Bilateral Incentive Mechanism Based on Social Relation and Evolutionary Game Theory

Peer-to-peer (P2P) file-sharing system has been developed rapidly over the past years. P2P file-sharing mechanisms such as Gnutella, BitTorrent and Private Tracker have been used popularly. The number of peers increases, the whole system for service capacity will increase accordingly. That is because that each peer can get the file content either from the server or from other peers who have the requested file. Each peer can offer upload and file sharing to other peers as well. However, the free rider and malicious node problems hinder the efficient utilization in P2P networks. Hence, this paper makes improvements on the original BitTorrent by proposing a novel bilateral incentive mechanism (NBIM) to restrain free rider and malicious nodes simultaneously. Furthermore, through the simulator with PeerSim, the simulated results prove that the proposed methodology can effectively restrain the free riders and malicious nodes via punishment and reward mechanisms.