Peer-to-Peer (P2P) online communities are commonly perceived as an environment offering both opportunities and threats. One way to minimize threats in such communities is to use community-based reputations to help estimating the trustworthiness of peers. This paper presents PeerTrust a reputation-based trust supporting framework, which include a coherent adaptive trust model for quantifying and comparing the trustworthiness of peers based on a transaction-based feedback system and a decentralized implementation of such model over a structured P2P network. PeerTrust model has two main features. First, we introduce three basic trust parameters and two adaptive factors in computing trustworthiness of peers. Second, we define a general trust metric to combine these parameters. Other contributions of the paper include strategies used for implementing the trust model in a decentralized P2P environment, evaluation mechanisms to validate the effectiveness and cost of PeerTrust model, and a set of experiments that show the feasibility and benefit of our approach.

[1] Li Xiong and Ling Liu, “PeerTrust: Supporting Reputation-Based Trust for Peer-to-Peer Electronic Communities”, IEEE Transactions on Knowledge and Data Engineering, Vol.16, No.7, July 2004.