Wake-On-Lan also known as WOL is the feature in a network card that enables a computer that is powered off to be turned on remotely. While trying to troubleshoot computers remotely there are times you may need to turn on a computer remotely to start your troubleshooting process. Since you cannot always walk up to these computers and power them on manually especially if the machine is located at a remote location. We use the Wake-On-Lan feature to instantly turn on the computer over a LAN or WLAN network. This can be done both internally or if configured properly externally.
Wake-On-Lan is mainly used to wake computers on the same network; however, it is possible to use port forwarding or QoS on a router to wake a computer up over an external network. The way WOL works is by sending a message also known as a magic packet to the target computer from another device or computer. Once the packet is executed the computer receives a signal which triggers the computer to turn on. If you are setting up WOL for use over an external network you need to make sure the device is properly linked to the IP or MAC ID and the router is forwarding all traffic on the specified port to that computer so the computer can receive the message or magic packet and turn on.
The main way to setup and enable WOL is by making sure your network card is capable of the WOL feature. This can be verified and determined by going to the network adapter properties and looking at the features. You should be able to find one called Wake-On-Lan. Once you find that you need to make sure it is enabled. After that is completed you need to log into your router by going to the designated IP address or by finding your Gateway through command prompt. Once you log into the router you need to go to the port forwarding section and forward the specified port for WOL. After that is completed make sure your firewall the port is allowed and whitelisted. Once that is done you should theoretically be able to wake your computer over the network both internally and externally.
The main reason most people use WOL is to make sure they can remotely start the computer and remote into their computer using Remote Desktop or a third-party remote desktop type tool such as TeamViewer, Join.me, LogMeIn, etc. Think about it like this, if you were out on vacation and only have a tablet on hand but a client or work called and asked you to fix an unexpected issue that arose on a project wouldn’t it be convenient to have the ability to log into your computer at work? Well, that’s definitely possible using Remote Desktop but what if the computer is off then what? Well as long as you have WOL set up you could turn it on and after a few seconds remote into the computer like it was always on and never off. Obviously, this is one of many scenarios.