ACC: Anonymous Cooperative Caching in Wireless Ad Hoc Networks

Cooperative caching is an effective approach to share cache copies among network nodes and then reduce data access cost in ad hoc networks. Since cached data may be privacy sensitive, privacy preservation should be considered. In this paper, we study this problem by achieving anonymity in cooperative caching. Our anonymous caching protocol borrows idea from anonymous routing protocols. Data query and access are realized based on anonymous hop-by-hop broadcasting. Pseudonyms are used in communications so as to protect the real identity. Security analysis confirms that our protocol can achieve sender anonymity, receiver anonymity, and communication anonymity. We also conduct simulations to evaluate the effect of anonymity mechanism on system performance. Different variants of anonymous caching algorithm and non-anonymous algorithms are simulated for comparisons. The results show that, anonymity will cause additional message cost and time cost, but the cost is reasonable. To the best of our knowledge, this is the first work on anonymity in cooperative caching.