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I'm using DSL modem manufactured by Billion (China, i think), i have 2 computers sharing this modem.

Now, I have a domain and want to A the domain to my modem's IP, however, when opening this IP, the management page of modem comes up.

Someone said to me that i can NAT some port of the modem to a LAN computer (either one of the 2 computers), but i don't really know how to do.

I opened the management page of modem and entered the NAT values, but it don't seem to work. please see the attached screenshot and help me

enter image description here

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to A the domain? – soandos May 31 '11 at 23:28
Are you trying to access it from OUTSIDE the local network? Your NAT probably isn't going to work internally. – Shinrai May 31 '11 at 23:34
NAT looks like it is setup right, but if you want to access it on the public IP from a private IP on the same network, you need NAT reflection. Is there a router on the other side of the modem as well? – MaQleod May 31 '11 at 23:47
@soandos: "A the domain", i meant setting a A record of the to my modem IP – jondinham Jun 2 '11 at 5:54
@Paul, I understand what NAT means. Connecting to the computer on the LAN from outside the network is different from connecting to the computer from inside the network using the public IP. One requires NAT plus port forwarding, the other requires NAT plus port forwarding plus NAT reflection. – MaQleod Jun 2 '11 at 6:22

I think what you're looking for is port forwarding; if you want to access a web page on a machine behind the router, then forward port 80 on your router to the private address of said machine (ie

For that to work, you may need to assign a static IP to that machine, or your DHCP server may be able to assign the same lease to that specific mac address.

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is assigning static LAN ip necessary? coz i have only 2 computers, and they are always .100 and .101 – jondinham Jun 2 '11 at 5:58
It isn't required, but it is a good idea. It may not matter today, or in a week, but it could cause you problems in the future if you don't use static IPs. – MaQleod Jun 2 '11 at 6:24
If your dhcp server supports it, you can also statically assign the same lease without having to configure the clients. This is especially useful if any of the machines are laptops, so you don't have to change profiles all the time. – Bryan Agee Jun 2 '11 at 14:57

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