The high potential of P2P infrastructures for enterprise services and applications both on the intranet (
project workgroups) and on the Internet (
B2B exchange) can be fully achieved provided that robust trust and security management systems are made available.
This paper presents the reputation system we have devised for SP2A , a P2P framework which supports secure role-based peergroups and service interactions. Our solution includes decentralized trust and security management able to cope with several threats. The underlying analytical model is introduced and discussed, together with a simulation-based evaluation of the robustness against malicious negative feedbacks.