Exploiting client caches to build large Web caches

Abstract New demands brought by the continuing growth of the Internet will be met in part by more effective and comprehensive use of caching. This paper proposes to exploit client browser caches in the context of cooperative proxy caching by constructing the client caches within each organization (e.g., corporate networks) as a peer-to-peer (P2P) client cache. Via trace-driven simulations we evaluate the potential performance benefit of cooperative proxy caching with/without exploiting client caches. We show that exploiting client caches in cooperative proxy caching can significantly improve performance, particularly when the size of individual proxy caches is limited compared to the universe of Web objects. We further devise a cooperative hierarchical greedy-dual replacement algorithm (Hier-GD), which not only provides some cache coordination but also utilizes client caches. Through Hier-GD, we explore the design issues of how to exploit client caches in cooperative proxy caching to build large Web caches. We show that Hier-GD is technically practical and can potentially improve the performance of cooperative proxy caching by utilizing client caches.