I have been struggling to get my Billion 7800N modem router to work with more than one static WAN IP addresses.

Basically, I run a small business with multiple servers, mainly mail-servers.

So I asked and got a block of 8 subnet IP addresses with 6 usable IP addresses (say from to They are external IP addresses, not for local network use. I then assigned each of these external IP addresses to each of my servers so that they are exposed to the outside world.

However, out of those 6 IP, I chose one for my router which then connects all my local computers, laptops on the LAN network (shielded from the outside world). Bear in mind that all the servers are connected directly to the BiPac 7800N modem router.

I assign IP address to my Billion 7800N modem router as a gateway with subnet mask

That's how I have got so far. I tried to turn off the NAT but couldn't despite having tried to save the config and restart it many times.

At this point, I could get on to internet and surf from my laptop which is assigned with one of those 6 IP for testing purpose with no problem. Then, I thought this is great, I hooked up all my servers straight to the 7800N modem router. Now, here comes the problem - no one from the outside world can access to my homepage which is hosted from one of my servers.

This tells me that I have no problem with outgoing traffic but the incoming ones as if something is blocking the incoming traffic. I checked the firewall on my BiPac 7800N and it's not turned on.

I did ask the billion support team and they got back to me with some irrelevant answers and then they stopped replying.

I'm at a loss. Any help would be greatly appreciated.

Thank you