HP StorageWorks Enterprise File Services WAN Accelerator Deployment Guide (November 2005)

62 7 - WCCP DEPLOYMENTS
Introduction to WCCP
WCCP was originally implemented on Cisco routers, multi-layer switches,
and web caches to redirect HTTP requests to local web caches (Version 1).
Version 2, which is implemented on HP EFS WAN Accelerators, can redirect
any type of connection from multiple routers to multiple web caches.
You configure WCCP to redirect traffic to an HP EFS WAN Accelerator or
group of HP EFS WAN Accelerators:
 so that the HP EFS WAN Accelerators do not have to be physically in-path
but can be logically in-path. That is, the HP EFS WAN Accelerators are
configured to be physically out-of-path devices while optimizing traffic as
if they were in-path devices.
 to redirect traffic to an HP EFS WAN Accelerator or group of HP EFS
WAN Accelerators to provide load balancing and failover support.
You configure WCCP on the client-side HP EFS WAN Accelerator; the server-
side HP EFS WAN Accelerator can be configured as an out-of-path device, an
in-path device, or a WCCP device.
Figure 7-1. Basic WCCP Configuration
The following steps describe how WCCP works with the HP EFS WAN
Accelerator:
1. Routers and HP EFS WAN Accelerators are added to the same service
group.
2. HP EFS WAN Accelerators announce themselves to the routers.
3. Routers send back the state of the service group.
4. One HP EFS WAN Accelerator takes a leadership role and tells the routers
how to redirect traffic among the HP EFS WAN Accelerators in the service
group.
The HP EFS WAN Accelerators use the following methods to communicate
with routers: