Is there any options in Basic/NAT firewall RRAS on SBS 2003?
Arani gave some instructions on how to set this up in the thread
I referred to previously.
We have Firewall enabled router, so I want is there any firewall for IP address filtering?
This will depend on the particular model you have. Not all of these devices have address filtering, but if your router has this feature, it will usually be found on the same menu where you set up "Port Forwarding".
as dalight said, you need to have ip filtering through an inbuilt firewall on your router. if your router does not support inbuilt firewall or inspite of having a firewall does not support ip filtering, then you are looking into the option of acquiring a router that does.