| So first, here are a couple of things that | | | | Ports Lets assume that a computer on the |
| you can do after you finish this section.- | | | | Internet needs to initiate a connection to a |
| You can configure BitTorrent to give you | | | | specific software on your computer. The |
| excellent speeds- You can configure your | | | | software in discussion uses port 12345. For |
| computer to play multiplayer games over the | | | | simplicity, we will call the initiating |
| internet- You can setup your computer as a | | | | computer as ClientX, and your computer as the |
| terminal server (for remote desktop | | | | ServerX. As we discussed earlier, clientX |
| connections)- and many many more cool | | | | only sees (and knows) the external IP address |
| stuff!!This tutorial consists of 2 sections1. | | | | i.e. the IP address of your router. It tries |
| Understanding Port Forwarding2. Implementing | | | | to initiate a connection to that IP address |
| Port Forwarding on common routersWhat is | | | | with the port number 12345. However, your |
| portforwarding?In one sentence, | | | | router recieves this request, and sees 4 |
| portforwarding makes the internet see your | | | | computers in your house connected to the |
| computer as if it were directly connected | | | | router. The router is not able to figure |
| rather than being connected though a router. | | | | which computer the connection from ClientX |
| For the same reason, if you dont have a | | | | was intended for! So it simply drops the |
| router, and your computer IS directly | | | | connection.Port forwarding is a setting in |
| connected to the Internet, then you wont need | | | | the router which you can change to prevent |
| this tutorial.A little explanation: When a | | | | this from happening. By doing this, you can |
| computer is connected to the internet, it is | | | | tell the router that any connections for port |
| assigned a unique address called the IP | | | | 12345 has to be forwarded to ServerX. Now |
| address. This enables other computers on the | | | | when the router recieves a request for a |
| internet to communicate with it and send | | | | connection on port 12345, it checks its table |
| packets to it and so on... An IP address has | | | | and sees your entry saying that all |
| the format ###.###.###.###. It looks like | | | | connections for port12345 have to be |
| four sets of numbers, separated by a dot. | | | | forwarded to serverX. Hence it routes the |
| Each set can have a value between 0 and | | | | connection accordingly!Here we'll see how to |
| 255.Usually the internet service provider is | | | | do portforwarding on most routers. Scenario : |
| the guy who assigns you an IP address for | | | | Lets say you need to forward port 6889 to a |
| your connection. However, he gives you only | | | | computer whose Internal IP is |
| ONE ip address and this gets assigned to the | | | | 192.168.1.10.Step 1: Find your gateway IP |
| cable/dsl modem at your house. If you | | | | address. To get this, in windows, select |
| directly connect your computer to the cable | | | | Start > Run. Type in "CMD" and hit enter. |
| dsl modem, you are using this IP address to | | | | Inside the command window, type "ipconfig" |
| communicate with other computers on the | | | | and hit enter. The screen will show you the |
| internet. However, you can connect only one | | | | default gateway. Note this down.Step 2: Open |
| computer to the cable modem at any given | | | | Internet explorer. Enter your gateway from |
| time. So you go to the nearest store and buy | | | | Step 1 in the address bar, and hit enter. A |
| a router.Role of the router A router connects | | | | popup window will ask you to authenticate |
| to the cable/dsl modem and splits the one | | | | into your router with a username and |
| internet connection into multiple connections | | | | password. Enter the username and password. If |
| so all the computers in your house can enjoy | | | | you dont remember, try the default ones |
| internet connectivity simultaneously. Once | | | | below:Linksys router : Default username "" |
| you get the router, you connect the router to | | | | password "admin" |
| your cable/dsl modem, and all your computers | | | | |
| to the router.Internal and External IP | | | | NetGear router : Default username "admin" |
| addresses Once you start using a router, the | | | | password"password" |
| IP address given by your internet service | | | | |
| provider gets assigned to the router. This IP | | | | Belkin router : Default username "" |
| address is called the External IP address, as | | | | password"" |
| it is part of the external network between | | | | |
| your router and the Internet. The router in | | | | D-Link router : Default username "admin" |
| turn assigns new IP addresses to the | | | | password"" |
| computers connected to it. These addresses | | | | |
| are a part of your Internal Network, and are | | | | Gateway router : Default username "admin" |
| called Internal IP addresses. By set laws, an | | | | password"admin" |
| Internal IP address may start with the | | | | |
| numbers 10,128, or 192. All the other | | | | If you cant remember the password, post it |
| combinations are used for external | | | | on the forum at and someone will help |
| addressing.For example, my external IP | | | | you!Step 3:For Belkin routers, select virtual |
| address is 68.36.145.156. This IP address is | | | | servers from the left menu. Enter something |
| assigned to my router. I have two computers | | | | for description. Type "6889" or the required |
| connected to the router, and they have the IP | | | | port number in both fields for inbound port. |
| addresses 192.168.0.10 and 192.168.0.11. | | | | Do the same for the Private port fields too. |
| These are my internal addresses.The Port | | | | Select the connection type from the drop |
| conceptEven when you use a router to connect | | | | down. If you dont know what you need, try |
| many machines to the internet, other | | | | UDP. If that doesnt work, come back and try |
| computers on the internet see one single | | | | TCP. In the private IP address field, enter |
| machine with the external IP address of the | | | | the computer to which you need the connection |
| router. They dont know that a router is | | | | forwarded. In our case, this is |
| sitting inside your house and splitting the | | | | 192.168.1.10Linksys routers, select |
| external address into many internal IP | | | | "Application and Gaming" from the top menu, |
| addresses. They can only make a connection to | | | | and the select 'portrange forwarding' from |
| your router, and your router decides how to | | | | the submenu. In another family of linksys |
| route the connection and to which internal | | | | routers, you can find 'Forwarding' section |
| computer to route it to.IP addresses are | | | | under 'advanced' tab of main setup page. Rest |
| further divided into channels called ports. | | | | of the process is the same as that for Belkin |
| This permits one IP address to be shared by | | | | routers above.Netgear routers, you'll find |
| multiple programs at the same time, each | | | | 'Port Forwarding' under the 'Advanced' table |
| using a different port. By standard every | | | | in the main page. The rest of the steps are |
| computer has 65536 ports (numbered 0 to | | | | same as above.Step 4:Save the setting and |
| 65535). When a computer attempts to talk to | | | | restart the router. Your port forwarding is |
| another computer, the attempt is always | | | | complete. |
| initiated along with a port number.Forwarding | | | | |