Linux iptables routing without NAT

Is it possible to use Linux iptables to provide routing between the
Internet and an internal network without NAT (i.e. so the static IP
addresses of the internal network are visible on the Internet) ? Any
advice on this matter would be appreciated. Thanks in advance.

-- vic

Vic Hargrave wrote:
> Is it possible to use Linux iptables to provide routing between the
> Internet and an internal network without NAT (i.e. so the static IP
> addresses of the internal network are visible on the Internet) ? Any
> advice on this matter would be appreciated. Thanks in advance.

You wouldn't necessarily be using iptables/netfilter for routing. You'd
just be using standard routing capabilities. You have two choices.

You could get your ISP to set up their routing so that whatever public
addresses are behind your gateway, they would route them through your
gateway.

Alternatively, you proxy arps for those addresses on your gateway's
external interface, then forward packets to your internal network
(usually natted, though).