Peer-to-peer file-sharing networks are currently receiving much attention as a means of sharing and distributing information. However, as recent experience with P2P networks such as Gnutella shows, the anonymous, open nature of these networks offers an almost ideal environment for the spread of self-replicating inauthentic files.

Abstract. We address the freerider problem on P2P networks. We first propose a specific participation metric, which we call a peer’s EigenTrust score. We show that EigenTrust scores accurately capture several different participation criteria. We then propose an incentive scheme that may be used in conjunction with any numerical participation metric. We show that, when these incentives are used in conjunction with EigenTrust scores, they reward participatory peers but don’t exclude less active peers. 1