Configuring the forward and return methods and adding authentication

The WCCP forwarding method determines how intercepted traffic is transmitted from the WCCP router to the WCCP cache engine. There are two different forwarding methods:

• GRE forwarding (the default) encapsulates the intercepted packet in an IP GRE header with a source IP address of the WCCP router and a destination IP address of the target WCCP cache engine. The results is a tunnel that allows the WCCP router to be multiple hops away from the WCCP cache server.
• L2 forwarding rewrites the destination MAC address of the intercepted packet to match the MAC address of the target WCCP cache engine. L2 forwarding requires that the WCCP router is Layer 2 adjacent to the WCCP client.

You can use the following command on a FortiGate unit configured as a WCCP router to change the forward and return methods to L2:

config system wccp edit 1 set forward-method L2 set return-method L2

end

You can also set the forward and return methods to any in order to match the cache server configuration.

By default the WCCP communication between the router and cache servers is unencrypted. If you are concerned about attackers sniffing the information in the WCCP stream you can use the following command to enable hashbased authentication of the WCCP traffic. You must enable authentication on the router and the cache engines and all must have the same password.

config system wccp edit 1 set authentication enable set password <password>

end