Abstract—Current unstructured peer-to-peer (P2P) systemslack fair topology structures, and take no consideration formalicious behaviors of peers. The main reason is that thetopology is not sensitive to peer’s trust, and cannot accommodateheterogeneity of peers over the network. Thus, afeedback credibility based global trust model is presented inthis paper. Then, based on the trust model, an adaptive topologyevolution mechanism for unstructured P2P networksis proposed. Through this mechanism, trusted peers canmigrate to the centric position, while untrusted peers to theedge of the topology, guaranteeing fairness during topologyevolution. On the other hand, the mechanism can effectivelycounter the malicious behaviors of peers, and also has theincentive functionality, which incents peers to provide morehigh-quality services in order to get more return on services.Analysis and simulations show that, compared with thecurrent topologies, the resulting topology mechanism demonstratesmore effectiveness and robustness in combatingthe selfish or malicious behaviors of peers.

Index Terms—P2P, topology evolution, trust, incentive mechanism

Cite: Jianli Hu, Quanyuan Wu, and Bin Zhou, "TTEM: An Effective Trust-Based Topology Evolution Mechanism for P2P Networks," Journal of Communications, vol. 3, no. 7, pp. 3-10, 2008.