Decoupling service and feedback trust in a peer-to-peer reputation system

Abstract

Reputation systems help peers decide whom to trust before under-taking a transaction. Conventional approaches to reputation-based trust modeling assume that peers reputed to provide trustworthy service are also likely to provide trustworthy feedback. By basing the credibility of a peer's feedback on its reputation as a transactor, these models become vulnerable to malicious nodes that provide good service to badmouth targeted nodes. We propose to decouple a peer's reputation as a service provider from its reputation as a service recommender, making the reputation more robust to malicious peers. We show via simulations that a decoupled approach greatly enhances the accuracy of reputations generated, resulting in fewer malicious transactions, false positives, and false negatives. © Springer-Verlag Berlin Heidelberg 2005.