Open a web browser like internet explorer or Netscape.

Enter the ip address of your router in the address bar of your browser. In the picture above the address bar has http://www.google.com in it. Just replace all of that with the ip address of your router. By default the ip address should be set to 192.168.2.1.

You should prompted for your password. Enter your password now. By default the password is blank. Click the Ok button to log in to your router.

On the left hand side click Initial Setup. This will bring you to another menu. Once again, on the left hand side click Special Application Ports. This will bring you to the following menu.

Enter the trigger port into the Trigger Port box. You can think of the trigger port as sort of a light switch for the public ports. When there is data flowing on the trigger ports, the public ports are on or forwarded. When there is no data on the trigger port, the public ports are off or not forwarded. Enter the ports you want to forward into the Public Ports box. These ports can be entered in a list like 45,47,49, a range like 400-500, or a combination of both like 45,47,49,400-500. Use the Trigger Type radio button to select the protocol type of the trigger port. Use the Public Type radio buttons to select the protocol type of the Public Ports. Be sure to put a checkmark into the Enabled check box.

When you are finished, click the Enter button at the bottom of the page to save your settings.

And that's it! You're done!