中文摘要：

为了解决动态P2P环境中的位置隐私保护问题,提出基于匿名链的位置隐私保护算法.不同于一般的K-anonymity方法,通过在用户查询信息转发的过程中构造一条匿名链来混淆身份信息与位置信息的一一对应关系,在完成查询的同时保护用户位置的隐私.针对一般P2P匿名存在的匿名组稳定性问题,该算法根据路网环境中移动对象的动态性,通过计算相邻移动用户之间的连通性对匿名链中间节点的选择进行优化.讨论匿名链构造的方法和中间节点优化选择的标准,对算法的安全性展开理论分析.通过实验验证了算法的可行性.实验结果表明,该算法在不同用户密度下都能够较好地完成匿名链的构造,保护用户位置隐私;同时,中间节点的优化方法可以在一定时间内显著提高匿名链的有效性.

英文摘要：

An anonymous chain based privacy protection algorithm was presented to solve the problem of location privacy protecting in dynamic peer-to-peer（P2P） network.Different from the general K-anonymity method,anonymous chain was constructed to break the one-to-one correspondence between the user identity and location information during the forwarding process of query message,and the location privacy was protected with the completion of the query.The algorithm optimizes the selection of intermediate nodes according to the stability of linkage between two nodes in order to deal with the dynamic issues in P2P environment.A connectivity matrix was introduced for the chain constructing algorithm and the security of anonymous chain was proved.A simulation on a real city map for the algorithm showed the effectiveness.The results prove that anonymous chain can be constructed in different density of moving nodes and the optimal intermediate nodes selecting method obviously improves the stability of the chain.