1. Log into your router. This is done by going to the URL box of your browser (such as Internet Explorer) and keying in one of these 2 series of numbers (properly known as an IP address):
If you’ve never accessed your router before you may be asked for a username and password. By default most routers set the username to “admin” and the password to “admin”. If the password is not admin you should try entering the serial number (the series of number and letters under the bar code on the back of the router) instead.
2. Find the port forwarding options within the router settings.
3. Enter the IP address of your console and the associated ports you need to forward.
For Xbox 360 users, you can find the console IP address by going into the System Settings then Network Settings and finally Configure Network. From here the IP address will be displayed on your screen. The required ports can be found by visiting this official Xbox page – http://support.xbox.com/en-US/xbox-live/connecting/network-ports-used-xbox-live
For Playstation 3 users, you can find your console IP by going to Settings > System Settings (press X) then go to System Information (press X). Along with some other details you’ll see your PS3′s IP address displayed on the screen. To find out exactly how to forward the correct ports you can check out this tutorial on Portforward.com – http://portforward.com/networking/staticip-ps3-playstation-3.htm
For PC users, you can find your IP address by simply going to Google.com and typing “What’s my IP” in the search bar. It will then state “Your public IP address is..” followed by a series of numbers that make up your IP. For a complete list of the ports you’re going to want to work with, be sure to check out this tutorial on WikiHow – http://www.wikihow.com/Set-up-Port-Forwarding-on-a-Router
Also if you go to the router page you can on some routers open the nat on the router page and just put your ip from PS3 under dmz mode
Read more: http://gamocial.com/xbox/black-ops-2/how-to-open-nat-type-for-black-ops-2/#ixzz2I5gtk0WK