Not all hits are created equal: cooperative proxy caching over a wide-area network

Abstract

Given the benefits of sharing a cache among large user populations, Internet service providers will likely enter into peering agreements to share their caches. This position paper describes an approach for inter-proxy cooperation in this environment. While existing cooperation models focus on maximizing global hit ratios, values of cache hits in this environment depend on peering agreements and access latency of various proxies. It may well be that obtaining an object directly from the Internet is less expensive and faster than from a distant cache. Our approach takes advantage of these distinctions to reduce the overhead for locating objects in the global cache.