Port forwarding
There are three main situations
1. You use a router with UPnP
2. You use a router without UPnP
3. You use a modem in bridged mode
If you don’t know which applies to you –
A router means you are using NAT, the WAN (Wide Area Network i.e. the Internet) IP is assigned to the modem/router, the modem/router can share the internet between multiple computers.
You will have to check your modem specifications to determine whether your router supports UPnP or not. If you don’t know or can’t find out, just follow the instructions for a router without UPnP. UPnP is a feature that allows programs to automatically forward ports in the router, when they are needed.
In bridged mode the WAN IP address is assigned to the computer you are using, that computer is fully open to the internet (unless you use a firewall of course, and you should). If you type “ipconfig /all” into a command window (Start…Run…”cmd”) it will display your WAN IP. Please note 192.168.*.*, 172.* and 10.* are not WAN IP’s. USB modems work in bridged mode. If you are using bridged mode, you do not need to port forward.
No matter which situation you are in, it is very advisable that you read your router/modems manual thoroughly.
Please choose the situation which applies to you (if you REALLY, REALLY, dont know try "without UPnP") –
1. I use a router with UPnP
2. I use a router without UPnP
3. I use a bridged modem