中文摘要：

为了提高P2P系统中交易的安全性和信任度量的准确性，提出一种基于模糊综合评判的推荐信任模型。充分体现节点间信任关系的模糊性、动态性，采用二层模糊综合评判方法来计算直接信任值，降低了人为赋值的误差，将交易金额和交易时间作为二层评判的权重。在推荐信任计算中引入节点交易密度函数和推荐共谋检测方法来计算推荐节点的推荐可信度。仿真结果表明，该模型可以有效抵御共谋推荐，对恶意节点有较高的检测率。

英文摘要：

To improve the security of transaction and the accuracy of measurement of the trust in P2P system, a recommendation trust model based on fuzzy comprehensive evaluation is proposed. In order to fully embody the fuzziness and dynamic of trust re- lationship between the nodes, a two-stage fuzzy comprehensive evaluation method is used to calculate the direct trust. To be more accurate, the transaction amount and transaction time is used to detemine the weight of second-stage comprehensive evaluation to reduce the artificial error. The transaction frequency and recommend collusion testing is used to measure the recommendation credibility of the recommenders in the calculation of recommendation trust. The simulation experiments show that the model can effectively prevent the recommend collusion, and has higher success rate in malicious node detecting.