Port forwarding usually used when we want our computer act like a router. Our computer receive the packet that come inside and then forward it into another destination.

For linux open shell konsole type:

Change the value in your /proc/sys/net/ipv4/ip_forward from 0 to 1. Or you can do by following the step below: echo '1' > /proc/sys/net/ipv4/ip_forward   For Windows XP, Vista, 7 In Windows, the default value for port forwarding is disabled, you should enable it and then start the service. Below is the step by step to enable port forwarding in Windows. 1. Click Run(read here to know the shortcut for RUN), 2. Type services.msc and then click OK, 3. In services windows, scroll down and find "Routing and Remote Access" services. You will find out that this service is disabled by default, you should enable it. 4. Right Click in "Routing and Remote Access" and click Properties. 5. Choose automatic to enable this service. 6. When finished, you need to start the service or you can right click and then choose start.   Hope this posts is useful for you.