Transparent Network Caching

Transparent Network Caching

A cache engine transparently caches as follows (figure below):

1. A user requests a Web page from a browser.

2. The WCCP-enabled router analyzes the request, and based on TCP port number, determines if it should transparently redirect it to a cache engine.

3. If a cache engine does not have the requested content, it sets up a separate TCP connection to the end server to retrieve the content. The content returns to, and is stored on, the cache engine.

4. The cache engine sends the content to the client. Upon subsequent requests for the same content, the cache engine transparently fulfills the requests from its local storage.

Because the WCCP router redirects packets destined forWeb servers to a cache engine, the cache engine operates transparently to clients. Clients do not need to configure their browsers to point to a specific proxy server. This is a compelling feature for ISPs and large enterprises, for whom uniform browser configuration is expensive and difficult to manage. In addition, the cache engine operation is transparent to the network—the router operates entirely in its normal role for nonredirected traffic.