摘要： 针对近年来对等网络中存在大量不安全服务的问题，提出一种基于云模型的信任机制。在符合查询操作的节点中，根据前若干周期的信任向量，利用灰色预测模型预测各个节点在当前周期的信任向量，设计云模型算法分别建立云模型，依据信任云决策算法和信任云相似度度量算法选出值得信任的节点为请求节点提供服务。仿真结果表明，该机制在选择目标服务节点时，不仅考虑节点信任值的平均值，而且还考虑信任值的离散性，可以从多个角度更全面、合理地选出最值得信任的目标服务节点，达到提高网络服务质量、增强网络安全性的目的。

关键词: 对等网络, 云模型, 灰色预测模型, 信任向量, 网络安全

Abstract: With the rapid development of Peer-to-Peer(P2P) network in recent years, there exist a lot of unsafe service problems. Aiming at this problem, a trust mechanism based on cloud model is proposed. A kind of cloud model algorithm based on node’s trust vector is proposed. For several nodes which matching the query condition, it uses gray theory to predict trust vector of current cycle based on its previous trust vectors, and creates cloud model for several current trust vectors, selects the trustworthy node to service the source query node depending on the decision algorithm of trust-cloud and the similarity measure algorithm of trust-cloud. Simulation experimental result shows that when selecting the target service nodes, this mechanism can not only depend on node’s mean trust-value, but also take trust-value discreteness into considering. So it can select the most trust node from different angles, improve the quality of network service, and achieve the purpose of enhancing network security.

Key words: Peer-to-Peer(P2P) network, cloud model, grey prediction model, trust vector, network security

中图分类号: 

• TP309