Caching large files by using P2P based client-cluster for web proxy cache

Many web cache systems and policies have been proposed. These studies, however, consider large sized objects less useful than small sized objects for the performance and evict them as soon as possible. Even if this approach increases the hit rate, the byte hit rate decreases and more bandwidth is used to obtain large sized objects. This paper suggests the web cache system which uses the client-cluster which is composed of the residual resources of clients as an exclusive storage for large sized objects. To manage the client-cluster, we use DHT based peer-to-peer lookup protocol which makes the system selforganizing, fault-tolerant, well-balanced and scalable. We manage the large sized object by the index based allocation method and balance the loads of all clients well. Consequently, this proposed system achieves not only the high hit rate but also the high byte hit rate, and reduces the outgoing traffics. We examine the performance of the cache system via a trace driven simulation and demonstrate effective enhancement of the proxy cache performance.