3com Webcache 1000 (3C16115) User Manual

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HAPTER
 2: I
NSTALLING
 
THE
 W
EBCACHE
In the Proxy Cache deployment the Webcache is connected to an 
Ethernet switch in your LAN. You must configure the Web browser on 
each client machine in your network to explicitly direct its Web requests 
to the Webcache. For more information on Web browser configuration, 
see “Configuring Web Browsers” on page 49.
All Web requests are received and served by the Webcache. All non-Web 
traffic bypasses the Webcache and is sent directly to the appropriate 
destination. 
If the Webcache fails, access to the Web is lost because each client 
machine has been configured to direct its Web requests to the 
Webcache.
You can avoid this loss of access to the Web by using Proxy Auto 
Configuration (PAC) files to configure the Web browser on each client 
machine. The PAC file can instruct the browser to go directly to the Web 
if the Webcache is not available. For more information, see page 50.
Transparent Cache
Figure 10   Transparent Cache Deployment
In the Transparent Cache deployment the Webcache is connected to a 
Layer 4 switch, router or firewall in your LAN which is capable of 
Redirection. The Layer 4 device (also known as a Layer 4 redirector or 
Web-enabled device) automatically redirects all Web requests to the 
Webcache. Therefore no configuration of the Web browser on each client 
machine is needed, which avoids configuration problems and reduces the 
demand on technical support.