The Magic Packet ( UDP) is typically send to port 9, some systems default to port 7, and some systems allow you to define your own port number. The magic packet is a 102 bytes long broadcast frame containing a of payload 6 bytes, all set to 255 (FF FF FF FF FF FF in hexadecimal), followed by 16 repetitions of the target computer’s 48-bit MAC address.Įxample (Mac Address = A2:3B:41:00:7A:9B): Note that theoretically WiFi supports Wake on Lan as well, however … not all computers and operating systems support this, so you milage may vary! While the NIC (network interface controller) is listening, a lot of traffic might pass that might not even be intended for this network connection, so just listening to network traffic would keep your network device awake even when you don’t want it to be awake. WOL also requires the network card of this device to be semi-awake, and still listen to traffic, just in case a “ magic packet” is being send to the device. There can be several motivations to do this save on power, save on wear-and-tear of your equipment, etc. WOL is probably most commonly used to wake up a server or NAS, just before access to these machines is needed – for example a media server, which can sleep all day long until you want to watch a movie. Wake On LAN, or WOL, is a Ethernet standard that allows you to “wake up” computers or network devices that are in stand-by, and is originally intended for use in a local network.
