Multiple NAT router

[Brett Glass]

I have an application in which I'd like a FreeBSD router to have 
multiple, isolated LANS attached to it, each with the same address 
space. The FreeBSD box would take the place of multiple NAT routers.

For example, I might want to have three internal Ethernet 
interfaces on the FreeBSD box. Each would be connected to a LAN 
whose internal addresses are 192.168.0.0/24. The FreeBSD box would 
do NAT for all of them, and of course they could not "see" one another.

The alternatives, of course, would be to install multiple NAT 
routers -- which would be a waste -- or to number the LANs 
differently. But the organization for which I'm doing this wants 
everything about each LAN to be absolutely standard (printers at 
the same static addresses, etc.) so that their IT guys can walk in 
and know exactly how everything's numbered.

Is it possible to do a "hydra headed" router such as this with 
FreeBSD? I'm not sure that FreeBSD's natd is equipped to sort 
incoming packets for multiple, identically numbered LANs properly, 
because it would have to remember interface names as well as 
addresses. Also, there would be the question of how one would 
connect inward to the machines on the LANs, since "ping 
192.168.0.100" would be  ambiguous. (Perhaps one could do it from a 
jail. In fact, perhaps the virtual NAT routers could be set up in jails....)

--Brett Glass