Wccpv2 Features - Cisco 6500 Series Software Configuration Manual

Chapter 35 Configuring Web Cache Services Using WCCP
Using WCCPv1, the cache engines were configured with the address of the single router. WCCPv2
requires that each cache engine be aware of all the routers in the service group. To specify the addresses
of all the routers in a service group, you must choose one of the following methods:
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The multicast option is easier to configure because you need only specify a single address on each cache
engine. This option also allows you to add and remove routers from a service group dynamically, without
needing to reconfigure the cache engines with a different list of addresses each time.
The following sequence of events details how WCCPv2 configuration works:
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2.
3.
The following sections describe how to configure WCCPv2 on routers so they may participate in a
service group.

WCCPv2 Features

These sections describe WCCPv2 features:
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Support for Non-HTTP Services
WCCPv2 allows redirection of traffic other than HTTP (TCP port 80 traffic), including a variety of UDP
and TCP traffic. WCCPv1 supported the redirection of HTTP (TCP port 80) traffic only. WCCPv2
supports the redirection of packets intended for other ports, including those used for proxy-web cache
handling, File Transfer Protocol (FTP) caching, FTP proxy handling, web caching for ports other than
80, and real audio, video, and telephony applications.
To accommodate the various types of services available, WCCPv2 introduces the concept of multiple
service groups. Service information is specified in the WCCP configuration commands using dynamic
services identification numbers (such as "98") or a predefined service keywords (such as "web-cache").
This information is used to validate that service group members are all using or providing the same
service.
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Unicast—A list of router addresses for each of the routers in the group is configured on each cache
engine. In this case the address of each router in the group must be explicitly specified for each cache
engine during configuration.
Multicast—A single multicast address is configured on each cache engine. In the multicast address
method, the cache engine sends a single-address notification that provides coverage for all routers
in the service group. For example, a cache engine could indicate that packets should be sent to a
multicast address of 224.0.0.100, which would send a multicast packet to all routers in the service
group configured for group listening using WCCP (see the ip wccp group-listen interface
configuration command for details).
Each cache engine is configured with a list of routers.
Each cache engine announces its presence and a list of all routers with which it has established
communications. The routers reply with their view (list) of cache engines in the group.
Once the view is consistent across all cache engines in the cluster, one cache engine is designated
as the lead and sets the policy that the routers need to deploy in redirecting packets.
Support for Non-HTTP Services
Support for Multiple Routers
MD5 Security
Web Cache Packet Return
Load Distribution
Catalyst 6500 Series Switch Cisco IOS Software Configuration Guide—Release 12.1 E
Understanding WCCP
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