A non-manipulable trust system based on EigenTrust

Abstract

A fundamental consideration in designing successful trust scores in a peer-to-peer system is the self-interest of individual peers. We propose a strategyproof partition mechanism that provides incentives for peers to share files, is non-manipulable by selfish interests, and approximates trust scores based on EigenTrust. The basic idea behind the partition mechanism is that the peers are partitioned into peer groups and incentives are structured so that a peer only downloads from peers in one other peer group. We show that the total error in the trust values decreases exponentially with the number of peer groups. In addition to theoretically guaranteeing non-manipulability, in practice our trust system performs nearly as well as EigenTrust and has better load-balancing properties.