World Wide Web caching: the application-level view of the Internet

Abstract

The Internet has fallen prey to its most successful service, the World-Wide Web. The networks do not keep up with the demands incurred by the huge amount of Web surfers. Thus, it takes longer and longer to obtain the information one wants to access via the World-Wide Web. Many solutions to the problem of network congestion have been developed in distributed systems research in general and distributed file and database systems in particular. The introduction of caching and replication strategies has proven to help in many situations and therefore these techniques are also applied to the WWW. Although most problems and associated solutions are known, some circumstances are different with the Web, forcing the adaptation of known strategies. This paper gives an overview about these differences and about currently deployed, developed, and evaluated solutions.

Web cache location

“…It follows that satisfaction of such requests at 2 c is not independent of satisfaction at 1 c . In fact 2 c is likely to have almost all the objects stored in 1 c provided its capacity is at least that of 1 c .…”

“…It is a viable approach since the request rate for documents is empirically found to approximate a Zipf distribution (Baentsch et al, 1997b) is just a normalisation constant and α is a parameter whose value is typically around 0.7 − 0.8, although values outside this range are not uncommon. This distribution has the consequence that around 40% of requests may be met by a proxy cache storing a very small fraction of one per cent of all the documents on the Web using a cache with a few Gigabytes of memory.…”

Tulip: A New Hash Based Cooperative Web Caching Architecture

“…Web caching techniques have gained great popularity on the Internet [1][2][3]18]. Since the number of proxy servers on the Internet increases rapidly, developing efficient and scalable cooperative web caching systems becomes an active research topic in recent years.…”

Proactive hot spot avoidance for Web server dependability

“…When dealing with static content, Web caching proxies (e.g., [22]) can be deployed between the servers and the clients (usually at the edge of an ISP) to store content close to the requesting site and make it available to other users [6]. Caching offloads the Web servers, while reducing access time and bandwidth consumption.…”