What's WOL and how does it work?

Wake-on-LAN (also referred as WOL and Wake on LAN) is a networking standard implemented by the modern computer devices. It permits waking up desktops connected to the Ethernet network by sending them a specific network packet. It is a standard for hardware, and, in most situations, it works independently of the software platform, so as far as you have a compatible motherboard, network card and power supply, you can use it on Windows, Linux, Mac and other platforms.

To wake up a remote workstation, you need to deliver a so-called magic packet to it. This packet contains the workstations's MAC address to be able to identify the target. The magic packet is distributed to all PCs in the local network throughout a broadcast and is processed by the computer that detects its own MAC address in the packet. To allow operation of this technology, the computer needs to not be turned off, because its network card and motherboard need to receive and analyze the network packets. You can shut the computer down to switch it into the low-power mode and hold only the necessary system running.

How you can setup WOL

Hardware and software configuration is a required phase to allow Wake-on-LAN operation on a PC. First of all, you have to enter the BIOS configuration and enable WOL there. You can refer to the motherboard documentation in order to have detailed guidelines on that. On Windows workstations, you need to also go to the network card properties in the Device Manager and turn on wake-up by a magic packet there. The specific configuration steps may vary for different network cards, and checking hardware documentation makes sense if you have difficulties with the configuration.

How you can initiate Wake-on-LAN

Despite the actual fact that Wake-on-LAN is one of the most frequently used remote operations, there is lack of basic support in the OS. For example, Windows doesn't offer a general WOL utility. Nevertheless, there are a number of utilities from software vendors. Some of them are free of charge, some are commercial, but all of them can be classified as either command-line or GUI tools. Command-line Wake-on-LAN utilities need that you enter the MAC address and the IP address of a remote PC. Most of GUI utilities require that you enter the same information thorough a visual interface. Such tools are good enough if you have to wake up only one and always the same computer. You can check its MAC and IP addresses once and then execute Wake-on-LAN every time with the same parameters. However, these tools are useless in a corporate environment where you have to wake up different or multiple PCs.

WOL for business users

What Wake on LAN functions are most helpful for corporate users? An automatic detection of MAC addresses and the capability to wake up multiple PCs at a time are the most important and wanted features of a Wake on LAN tool to be used in a corporate environment. Usually they are available in Wake-on-LAN tools designed for large networks. Most advanced of them are able to detect MAC addresses even for powered off computers in seconds and also wake up hundreds and thousands computers in few minutes. Usually they contain scheduling features to make possible an automatic WOL execution at a defined time. You are able to setup such tool once and it will take care about turning on of network computers.