What Is Port Forwarding
Port forwarding allows access to an application from outside your network. Port forwarding is done on your router. When you port forward, DNS requests to your routers external IP forwards to another external IP. Here is a good (but fast) explanation of how this works.
Isaac's Computer Tips
Issac, put a great video together that covers the same information as this article. Check it out so you can see what we write about below.
Public IP Address
Public IP address is a unique identifier for your internet connection. Accessible to the public. This is your router’s external IP. There are no open ports on this address. You can find your external IP by typing “What is my IP” into Google.
Private IP Address
192.168.0.5 is the general look of private IP Address. A private IP is unique to the specific computer or device on a local network. These addresses are only on your device and in your network. Lots of computers and devices all around the world will have that same IP address and that is OK, because it is only on the local network.
If the public IP address is the address of a house, the private IP address is the location of a room in that house.
You can find your Private IP Address by looking in the DHCP section of your router’s configuration. You can also set MAC addresses to a static IP through your router’s DHCP settings.
Software listens for traffic on the port and the port identifies which application should handle the request. Ports allow direct interaction with an application.
Directs outside requests to your public IP to a private IP that is inside your network.
Port Forwarding sends incoming traffic from outside the network to a local computer based on the requested port. So you are configuring what local IP should be receiving requests for port 80.
Setting Up Port Forwarding
This is done in your router. You can log into your router by typing your router’s local IP address into your web browser. Sometimes your router’s IP and login credentials are listed on a label on the back or bottom of your router. It will generally look like 192.168.0.1
Every router’s web interface is different, so this makes it tricky to document exactly how to configure your router. Sometimes you will see a section called Application Settings and it will have common rules you can set depending on what application you are setting up, such as a game server or a web server. There may also be a Port Forwarding section where you can set up forwarding rules manually.
Each port can only be assigned to one internal IP address.
You can also assign a static internal IP to the mac address of a specific machine. This is handy because the static IP will not change if you cycle your router. This is done in the DHCP section of your router.