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Chapter 4: Configuration
Configuring Web Caching
Web caching allows HTTP requests from connected users to Internet sites to be redirected
to cached Web objects on local servers. Response time is faster since requests can be
handled locally and overall WAN bandwidth usage is reduced. The IA itself does not act
as a cache for web objects. Instead, it redirects HTTP requests to one or more local servers
on which the web objects are cached. To configure web caching, first define the local
servers that are to be used to cache web objects. Then, apply the caching policy to the
(outbound) interface on which you want HTTP traffic to be redirected to the cache servers.
Using the policy-based routing example shown previously in Figure 9, HTTP requests
from both "standard" and "premium" users will be cached on three local servers, as
shown in Figure 10. Because there are two outbound interfaces (one for the T1 link and
one for the T3 link) to which caching policies must be applied, two separate caching
policies will be created that will contain the same caching servers.
Internet
T1
T3
The following are the basic steps for configuring the IA:
1.
Create the VLAN on which the web caching servers will reside.
The following commands create the IP VLAN 'twcr,' which consists of ports et.1.3,
et.1.4, and et.1.5 (the ports to which the web caching servers are connected to the IA):
ia(config)# vlan create twcr ip id 2
ia(config)# vlan add ports et.1.(3-5) to twcr
2.
Specify an interface to the VLAN you just created and assign an address-netmask
value to the interface.
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Web Caching Servers
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Figure 10. Web Caching Example
P rem ium
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HBT
DIAG
Internet Appliance 1100/1200 Getting Started Guide
Standard
Users
Remote
Access
Server
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