基于增强稳定组模型的移动P2P网络信任评估方法

Enhanced Stable Group Model-Based Trust Evaluation Scheme for Mobile P2P Networks

目前,己经有许多文献给出了移动P2P网络环境下信任管理技术与具体应用的集成方案.现存的信任模型都存在一个共同的假设,即假设信任信息都来自于稳定的网络拓扑结构环境下,且这些信任信息能够被保证长期有效.然而移动P2P网络由于节点频繁的加入和退出造成网络拓扑结构不断变化,不可能保证建立的信任信息长期有效.因此,已有的信任管理系统在这种移动环境下已经不再适用,迫切需要提出新的解决方案.通过研究移动P2P节点的信任关系的变化与网络使用者的兴趣、爱好等变化的对应关系,该文提出了一个基于增强的稳定组模型(Enhanced Stable Group Model-based Trust Evaluation Method,SGTM)的信任评估方法,并给出了稳定组构造算法.该机制利用稳定组构造算法对移动P2P网络进行有效地分组,相同分组内的节点之间相对保持最大程度的拓扑结构的稳定,从而保证组内节点信任关系的稳定存在.文中在移动环境下对移动模式和信任管理之间的关系问题进行了详细的研究.模拟实验从动态适应力、全局信誉的收敛时间以及全局信任计算所涉及的通讯负载等方面对所提出的信任评估方法的性能进行了评估.

Although many researchers have studied the establishment and maintenance of trust in mobile P2 Pnetworks,the existing approaches to trust establishment usually require a lengthy process and assume long term validation.In contrast,few of these characteristics are prevalent in mobile P2 Pnetworks with their unreliable transmission medium,frequent topology changes and variable network lifetimes.Since those solutions developed mainly for the fixed wired networks are not fit in such a scenario,new security solutions are eagerly in demand.In this paper,we propose an Enhanced Stable Group Model-based Trust Evaluation Method（SGTM）.Stable group is introduced in collecting trust evidences phase to simplify the process of trust initialization.In the scheme,all group members that move in a similar pattern remain throughout the entire communication session.By doing this,the topology within a group is less dynamic.Since trust evidences of a sensor are main collected in the stable group,the average length of trust chains is much shorter and more robust than other models,and avoids trust dilution.The simulation results prove the effectiveness and the benefits of the proposed model.