Routing Real IP with Redhat BOX GW to a client.

I want to control bandwidth with CBQ and Proxy from a Linux box, which I want to make gateway for a user. I don’t want to add route in the Cisco router.

The gateway machine has two Ethernet cards and Redhat 7.3.

Can I route real IP to the end user or do I have to just go with the fake IP?

OR

If someone can help me with ideas I will be grateful. Does there have free software to work on the GW to do the routing for me?
:help: :help: