Installation guide

Using transparent proxy
In a transparent proxy deployment for high availability, traffic forwarding may be
accomplished using a Layer 4 switch or a WCCP-enabled router. Routers or switches
can redirect traffic to the proxy, detect a failed proxy machine and redirect its traffic to
other proxies, and perform load balancing.
Using a Layer 4 switch. In one simple form of transparent proxy, a hard-coded rule is
used to write a proxy’s Media Access Control (MAC) address as the destination
address in IP packets in order to forward traffic to that proxy. Traffic that does not
include the specified proxy address for forwarding is passed directly to its destination.
The following figure illustrates this deployment:
As described for the explicit proxy, virtual IP addresses can be used in this scenario to
enhance availability in case a proxy machine fails.
Using a WCCP-enabled router. WCCP is a service that is advertised to a properly
configured router, allowing that router to automatically direct network traffic to a