WCCP

A summary on WCCP:

WCCPv1

• Only a single router services a cluster of systems
• Supports HTTP (TCP port 80) traffic flows only
• Provides generic routing encapsulation (GRE) to prevent packet modification
• Routers and cache engines communicate to each other via a control channel based on UDP port 2048

WCCPv2

• Allows for use across up to 32 routers (WCCP servers)
• Supports up to 32 engines/accelerators (WCCP clients)
• Supports any IP protocol including any TCP or UDP
• Supports up to 256 service groups (0-255)
• Adds MD5 shared secret security

Configuration:

Enable WCCP:

R1(config)#ip wccp web-cache

Optional things for the global command

Redirect-list: what traffic gets redirected to the web-cache (eg: send only requests from 192.168.0.1)
Group-list: which cache server gets used
Password: credentials for auth cache.

If the web-cache is in the same interface that requests are coming in:

R1(config-if)#ip route-cache same-interface

Outside int where requests go (Internet facing connection):

R1(config-if)#ip wccp web-cache redirect out

Inside int where requests come in (LAN connection):
R1(config-if)#ip wccp web-cache redirect in

Verification:

R1#show ip wccp web-cache detail

Wikipedia WCCP
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