Bringing the web to the network edge: large caches and satellite distribution

The World Wide Web is growing exponentially and already accounts for a big percentage of the traffic in the Internet. Popular Web servers are overloaded, hot documents travel many times across the same congested links, and receivers experience slow response times. Cache hit rates can be significantly increased by having caches cooperate. In this paper we analyze a scenario where caches cooperate via a push-satellite distribution [16] [6]. When a cache fetches a new document, the document is immediately broadcast to all other caches via the satel-lite. Caches connected to the satellite distribution end up containing all documents requested by a huge com-munity of clients. The probability that a client is the first to request a document is very small. An ISP with a large cache connected to a push-satellite distribution can achieve bandwidth savings up to 90 %. Clients with local caches connected to the satellite distribution can alleviate the last mile problem and virtually browse the whole Web locally. We evaluate the feasibility of a satellite distribution to local caches and perform a quantitative analysis in terms of hit rate, latency, satellite bandwidth, and storage requirements. We also discuss how to schedule the push operation and present several techniques to filter non-desired documents.