Web Caching and Replication

Part II: Web Caching

Part II concentrates on issues surrounding forward caching, or more specifically, forward proxies. Recall from the Introduction that forward proxies operate on behalf of the consumer of Web content: a forward proxy attempts to improve Web access to a selected group of Web clients no matter which Web sites these clients access. To origin servers, forward proxies look a lot like any other Web clients that consume their content. In fact, before HTTP 1.1 introduced the via request header, origin servers could not even tell if a Web request came from a browser or a forward proxy.

The decoupling between forward proxies and origin servers and the resulting lack of control of the latter over the former is a fundamental issue with ...