内容中心网络中面向隐私保护的协作缓存策略

针对内容中心网络节点普遍缓存带来的隐私泄露问题，在兼顾内容分发性能的基础上，该文提出一种面向隐私保护的协作缓存策略。该策略从信息熵的角度提出隐私度量指标，以增大攻击者的不确定度为目标，首先对于缓存策略的合理性给予证明；其次，通过构建空间匿名区域，扩大用户匿名集合，增大缓存内容的归属不确定性。缓存决策时，针对垂直请求路径和水平匿名区域，分别提出沿途热点缓存和局域hash协同的存储策略，减小缓存冗余和隐私信息泄露。仿真结果表明，该策略可减小内容请求时延，提高缓存命中率，在提升内容分发效率的同时增强了用户隐私保护水平。

A Collaborative Caching Strategy for Privacy Protection in Content Centric Networking

How to mitigate the privacy attacks related to the ubiquitous presence of caching poses challenges to the content delivery in Content Centric Networking. On the basis of trade-off between content distribution performance and users privacy, a collaborative caching strategy for privacy protection is proposed. First, the privacy metrics are designed and the rationality of the proposed strategy is demonstrated by applying the concept of information entropy. And then, the anonymity domain is constructed to increase the uncertainty of which nearby consumer recently requested certain cached content. When making the caching decision, in order to eliminate the cache redundancy and privacy leaks, the hottest on-path caching and the collaborative hash caching are proposed for the vertical requesting path and horizontal anonymity domains, respectively. The simulation results show that the strategy can decrease the request latency, increase the cache hit ratio, and enhance the protection of users privacy while improving the efficiency of content distribution.