Interception Strategies; Using A Layer 4 Switch With Cache Switching Functionality To Filter Transparency Requests - HP P4535A - Web Cache Server Appliance Administrator's Manual

Chapter 4

Interception strategies

Routing solutions enable transparent interception of Internet requests. The transparency routing solutions
supported by Traffic Server are:
A Layer 4 switch.
See "Using a layer 4 switch with cache switching functionality to filter transparency requests" on page 23.
A Cisco IOS-based router using the Web Cache Control Protocol (WCCP).
See Using a WCCP-enabled router for transparency‚ on page
Policy-based routing.
See Using policy-based routing to filter transparency requests‚ on page
Software routing.
See Interception bypass‚ on page
How client requests reach Traffic Server depends on network topology. In a complex network, you must
decide which clients are to be served transparently and make sure that Traffic Server is positioned to intercept
their requests. Traffic Server, or routers or switches feeding Traffic Server, are often deployed at a major artery
or aggregation pipe to the Internet.
ARM is installed by default and must be activated to use transparency. The section "ARM redirection" on
page 22 describes configuration details.
Using a layer 4 switch with cache switching functionality to filter transparency
requests
Layer 4 switches have the ability to rapidly redirect supported protocols to Traffic Server, while passing
all other Internet traffic through directly to its destination. Figure 4-1. below illustrates this scenario for
HTTP.
28.
end users
L4 switch
all
Figure 4-1. Using a Layer 4 switch to filter HTTP requests
24.
Internet
all
80
Traffic Server
Transparent Proxy Caching
27.
23