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I have a valid IP address set on my router. I want to map the IP address to my server running windows server 2008 r2 enterprise, But I don't know how to do it! Can any body please help me with this? I also need to forward my ports from modem to CRM application, any guide on this? Thanks in advance However, I know how to use the wizard to set static IP address!(LAN properties->IPv4 Properties), my problem is that my ISP has offered default gateway and subnet mask addresses in my modem's page, which are different from those I can see in CMD window when I type ipconfig command, So, should I set these addresses too? Because when I tried, I got a warning message! Help me please!

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what is the model/make of the router? – Renju Chandran chingath Jul 17 '13 at 8:01
What is your network layout? Are your computer and the server in the same LAN? – gronostaj Jul 17 '13 at 8:06

In general, what you can do is setup your router with the IP address given by your ISP in WAN settings page and configure your LAN with static IP, configure you server with a static ip,say or something with reference to the router LAN settings. goto the page for forwarding ports and give your server IP address port number and protocol there.

PC's connected to the router uses the default gateway IP as the routers IP, thats why you get different address in cmd. need to know about which router you are using to help out you more

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I can't find my router model right now. all I know is that it's a D-Link router.I called our ISP and asked for their help. They led me to my router page with "system" as both username and pass, then under Router & Bridges I clicked apply. It did some rebooting and then the guy told me my valid IP is now set on my server! I have to check it from outside our LAN(e.g from the Internet)! – Fereshteh Jul 17 '13 at 10:35
"my problem is that my ISP has offered default gateway and subnet mask addresses in my modem's page, which are different from those I can see in CMD window when I type ipconfig command" could you please make it more specific? – Renju Chandran chingath Jul 18 '13 at 4:59

The settings ISP gave you have to go into the router's configuration, particularly the network interface facing the ISP. There should be an IP address, netmask and a default gateway (optionally DNS addresses). The other network interface facing your local area network can have addresses of form (192.168.X.X, 172.16.X.X, 10.X.X.X/8).

For port forwarding you have to configure NAT (Network Address Translation) on your router and map the [Local IP Address]:[Local Port] to outer interface's [IP Address]:[Outside Port].

For ex. you want to NAT a web server to outside world. Web server is and outside address is, then create a rule in NAT configuration like:    -> or or whatever port you like

But for more precise info please describe your equipment and addressing scheme a little bit more.

PS. I am sorry for posting that as an actual answer, but don't have enough rep. for commenting.

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Thanks @Alexander, Actually our company wants to access CRM software inside our LAN from outside(e.g the Internet) and also we are setting a SMS service on CRM, which we want to have the ability to receive incoming SMSs on. So we bought a valid IP which is set on our router. As I've found out until now, for these services we don't need port forwarding. In addition, I have to set the valid IP address on our server. I hope you've understood my situation. – Fereshteh Jul 17 '13 at 8:08
You should not use a public, globally routable, valid IP address as an example. There are "documentation" IPv4 address ranges specifically allocated for purposes like this; see RFC 6890 section 2.2.2. – Michael Kjörling Jul 17 '13 at 9:51
@Michael Kjörling, yeah forgot about that. But who cares, it's a public Google's DNS server – Ashtray Jul 17 '13 at 9:53
You could in principle say the same for, but I'm not sure the administrators of would agree. TEST-NET-1, TEST-NET-2 and TEST-NET-3 have been specifically allocated for this purpose, and you might be surprised how literally some people can take things like IP address examples. Best, then, to at least use an example that will never conflict with anything real. – Michael Kjörling Jul 17 '13 at 9:57
@Fereshteh, so if I understand correctly now, you want to assign the public IP to the server? You have several of them? If so, that's still NAT, but your router must support that kind of NAT. You cannot just set the same address for the server as is used by router's WAN interface. You can only forward some ports of that address or NAT a completely different address – Ashtray Jul 17 '13 at 10:01

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