Abstract: A bi-directional mechanism, BDS_R, was proposed to deal with the deficient fairness and low effectiveness in trust model. The BDS_R mechanism granted the selection freedom to the request peer and service peer for providing better services actively and increasing the transaction success rate. Experimental results show that: bidirectional selection mechanism based on trust has higher transaction success rate, and better performance in avoiding network resource waste, reducing network flow, and motivating peers.

Key words: P2P, reputation, bi-directional selection, incentive mechanism

摘要： 针对P2P网络中信誉模型公平性有所欠缺，节点不能很好被激励的问题，提出一种基于信誉的双向选择机制BDS_R。BDS_R同时给予请求节点、服务节点选择的权利，以刺激节点积极贡献优质资源、提高交易成功率。实验结果表明，以信誉为基础的双向选择机制具有较高的成交率，在避免网络资源浪费、减少网络流量开销、激励节点方面起到了一定的成效。

关键词: P2P, 信誉, 双向选择, 激励机制