Share-Ratio-Based Incentive Mechanism for File Sharing With BitTorrent Protocol

Abstract

Several P2P file-sharing networks were successfully deployed and are used by millions of Internet users globally to share files (such as movies, video clips, software systems, e-books, etc.) cooperatively over the Internet. These networks were designed with cooperation in mind, therefore, several incentive mechanisms were devised to encourage cooperation among downloaders and yet the free-riding phenomenon remains a threat to these networks since free-riders could indulge in acts such as whitewashing, Sybil, and collusion attacks to escape penalties imposed by the incentive mechanisms. This paper proposes a share-ratio-based incentive mechanism for P2P file-sharing networks where files are shared via BitTorrent protocol. The proposed incentive mechanism is not prone to Sybil and collusion attacks, and it was designed to simultaneously: (1) encourage cooperation, (2) provide fairness to new downloaders, and (3) deter freeriding while resisting whitewashing attack. The proposed incentive mechanism does not require any central entity to be realized and it was designed in existing terminologies used in P2P file-sharing networks, hence, it is easy to implement. In addition to the accomplishment of the set objectives, the proposed incentive mechanism has successfully deterred free-riding as shown by the experiments conducted.