Transparent bridge and QoS controls
 

I have a cable modem and 5 IP addresses on it. I have a couple servers connected to it now, and realize that I would like to control QoS on a service level. I dimly remember a way to configure IPCop to work in a bridge mode so that I could control QoS, but (here's the key), not use one of the IP addresses on the public side - a transparent bridge. You had to add another interface to it that had a private IP so you could manage it, but that was the only IP it actually used.
Are there any new projects out there that can offer functionality like this? I can dedicate a machine to this, but want it to be transparent to my current infrastructure - the servers that have public IPs need to keep those public IPs, but have their bandwidth controlled (ie: give priority to VoIP).
Thanks!