Web Caching and Replication

Chapter 14. Basic Mechanisms for Request Distribution

As we mentioned in the introduction to Part III, this book focuses on transparent replication: replication techniques that require no user involvement or even awareness of whether or not a Web site utilizes replication. Transparent replication requires that clients use a single logical name when requesting a resource, regardless of the physical server that ends up processing the request. So a fundamental requirement of transparency is a mechanism for the redirection of logically identical requests to distinct servers.

There are a variety of points on the request processing path where such redirection may occur: at the client, at the intermediate proxies, at various points in the DNS system, ...