If you don't know what Port Forwarding is yet, you might want to start by reading our What is Port Forwarding guide.
You might also be interested in our huge collection of Router Screenshots where you can see every page of every router that we know of.
Now we need to know your routers IP address. You can find it a variety of ways.
It's ok if you don't know your 2wire 3800HGV-B router's internal IP address. You can find it by doing one of the following:
Open a web browser like Internet Explorer or Firefox. Enter the internal 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 internal IP address of your 2wire 3800HGV-B router. By default the IP address should be set to 192.168.1.254.
If you are having trouble with this guide, then perhaps PFConfig may be your solution. PFConfig is a software tool that will automatically forward ports for your router to save you time and hassle.
Now that you are logged in to your 2wire 3800HGV-B router you should see the following:
Look for your password on the bottom of your router or in the paperwork that came with your router.
Click the Firewall button.
Click the Firewall Settings button.
Use the Select a computer box to choose a device to forward ports to. This box contains a list of device names that are visible on your network.
Click the Add a new user-defined application link.
Enter the name of the program into the Application Name box. It doesn't really matter what you put into this box, but something that will remind you why these ports are being forwarded would be a good idea.
Select the protocol type using the Protocol radio button. If you need both TCP and UDP, create a duplicate configuration. The first configuration should have TCP selected, while the second one should have UDP selected.
If you are forwarding a single port, enter that port number into the Port (or Range) From and the Port (or Range) To boxes. If you are forwarding a range of ports, enter the lowest number of that range into the Port (or Range) From box. Then enter the highest number of that range into the Port (or Range) To box.
Enter the protocol timeout into the Protocol Timeout (seconds) box. The protocol timeout should be set to 86400 if you are using the TCP protocol, or 600 for the UDP protocol.
Go ahead and leave the Map to Host Port box empty.
Leave Application Type set to None.
Click the Add Definition button.
Click the Back button.
Select the applications you just created in the Applications list, then click the Add button to move them to the Hosted Applications box.
When you are finished, click the Done button at the bottom of your screen.
And that is it! You are done!
Now that you have forwarded ports for any port on the 2wire 3800HGV-B you should test to see if your ports are forwarded correctly.