Port forwarding is the act of configuring a router to make a computer or network device that is connected to it accessible to other computers network devices outside the local network. In other words, when you turn on port forwarding on your device you are turning on remote internet access for it.
Port forwarding allow computer over the internet to connect to a specific computer or service within a private network. It’s basically making your computer accessible over the internet even though you are behind Router.
Remote Desktop service is a service built in the Microsoft Windows that enables you to connect to another computer running Microsoft Windows. Once you are connected to a remote computer you can use that computers program and files Just as if you are sitting in front of it.
Suppose your friend wants to connect to your desktop computer. He starts up the remote desktop connection and send the request to your public IP address with a specific port number. Port is not a physical connection but it’s a logical connection that is used by humans and services to exchange information and uniquely identify these programs and services that are running on a computer.
Let’s see in this case remote desktop connection uses port 3389. So, the request with the port number will make its way through the internet to your router and once it reaches, your router needs to know where to forward the request for Port 3389. Because without any port forwarding configured your friend will not be able to connect to your computer.
By default router does not know what to do with this request? So, this is where port forwarding comes in. Where we have to tell router to send and forward any request that come in with port 3389 and send the request to our computer.
Let’s elaborate it with an example
Let us say you have an IP camera connected to a router and there is also a computer connect to the same router. Router assigns the camera and the computer and internal IP address so that you can communicate with each other on the local area network. Local IP address almost starts from 192. Or 10. The router is connected to a cable modem to provide internet access to a computer.
On the network Modems also sign in IP address but they are different than local IP addresses assigned by the router. The internet service provider assigned a modem a public IP address.
The public IP address is what enables communication between a Local Network and devices on the Internet .By default most routers have a Firewall enabled so that no outside internet traffic can enter the local network.
This is why port forwarding is needed. If you want to enable remote access to devices Such as IP cameras. When you setup port forwarding a hole in essentially poked through the firewall, which allows internet traffic inside the network but only on a specific port that you can forwarded.
Suppose an IP Camera is running on port 7000. If you set up port forwarding on the router endpoints port 7000 to the IP camera. Outside traffic will not be allowed inside the network on the particular port. The router will forward the communication to the IP Camera when it comes over the Internet. Port forwarding works exactly the same way for networks DVRs and other type of network able device.
Here are the steps to setup port forwarding using the Cisco Linksys router
- Login to the web interface of the router.
- Go to the security settings. In the security settings there is a section called apps and gaming. There is a sub section called single port forwarding.
- There will be certain entries for convenience let’s talk about IP Camera.
- There you can see the forwarded port (number) to internal IP address of the IP Camera.