The Web Cache Communication Protocol (WCCP), developed by Cisco Systems, specifies interactions between one or more routers (or Layer 3 switches) and one or more web-caches. The purpose of the interaction is to establish and maintain the transparent redirection of selected types of traffic flowing through a group of routers. The selected traffic is redirected to a group of web-caches with the aim of optimizing resource usage and lowering response times.
Squid v2.3 and above supports WCCP v1
Squid v2.5 now supports WCCP v1 and WCCP v2 1?
Microsoft Proxy or ISA doesn't appear to support WCCP
In English, WCCP is a way for a cisco router to check that a web proxy is up and where it is so that it can transparently redirect web traffic at it. This is the idea behind transparent proxying that your ISP uses to confuse your browser ;)
Without having to have a proxy server connected between the LAN and the Internet, like you have to with Microsoft ISA, SBS 2000, etc, you can force all your users to use the proxy server without having affect the client settings on all the clients.
Traffic is only redirected on port 80. However, on WCCP v2, you can set up WCCP to redirect traffic on other ports.
Should your proxy server fail, the client's connection to the Internet won't be affected . That means you can also take a proxy server off line at any time.
You can deploy multiple proxy servers for redundancy. With WCCP v2, it will do load distribution as well.
With WCCP v2, you can use the same proxy server, or the same stack of proxy servers, on a site with more than one connection to the Internet.
WCCP v2 also supports Web Cache Packet Return, whereas the router will bypass the proxy if the proxy rejects packets.
WCCP v2 also supports MD5 Authentication between each router and each proxy server - Sorry Sahil :-)
1?WCCP 2.0 Implementation in Squid 2.5
Following several customer requests, we have completed the required development work for WCCP 2.0 support for Squid version 2.3 and above. At present all Squid versions supports WCCP 1.0.
WCCP 2.0 supports mutliple router and cache server implementations in a network, it also supports MD5 authentication security between the cache server and routers.
Thanks to members of the Squid developer community, this fully integrated enhancement for WCCP 2.0 support is currently in QA, and will be submitted to Squid Open Source in the very near future. The reader may click here to preview the corresponding CVS branch under the Squid source tree.
