Cisco Catalyst 4500 Series, Software Configuration Manual

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 81 Configuring WCCP Version 2 Services
Understanding WCCP
Understanding WCCP Configuration
Multiple routers can use WCCP to service a cache cluster. Figure 81-1 illustrates a sample configuration
using multiple routers.
Figure 81-1 Cisco Content Engine Network Configuration Using WCCP
The subset of content engines within a cluster and routers connected to the cluster that are running the
same service is known as a
service group . Available services include TCP and User Datagram Protocol
(UDP) redirection.
WCCP requires that each content engine be aware of all the routers in the service group. You must a list
of IP addresses for each of the routers in the group configured on each content engine. The address of
each router in the group must be explicitly specified for each content engine during configuration.
The following sequence of events describe how WCCP works:
1.
Each WCCP client (content engine) is configured with a list of WCCP servers (routers).
2.
Each content engine announces its presence with a
Here I Am
message and a list of routers with
which it has established communication.s The routers reply with their view (list) of content engines
in the service group through
I See You
messages.
3.
If the view is consistent across all content engines in the cluster, one content engine is designated
as the lead and sets the policy that the switches deploy in redirecting traffic.
WCCP Features
These sections describe WCCP features:
•
HTTP and Non-HTTP Services Support
•
Multiple Routers Support
•
MD5 Security
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100BASE-T
100BASE-T
100BASE-T
100BASE-T
100BASE-T
100BASE-T
Clients
Clients
Clients
Clients
Clients
Clients
Service group
Cache 1
Cache 2
Cache 3
Internet