LANOff monitors network connections and optionally initiates computer shutdown if the network connection to specified computers is lost. It can be initiated either manually or automatically via the Windows Task Scheduler. The shutdown delay and many other parameters can be configured via the configuration screen. LanOff is part of the JSutils group of software utilities which have a theme of energy conservation. Requires a registration code (free for personal non commercial use).
This freeware program operates by interrogating each remote computer via a small slave program once a second. Up to four remote computers can be monitored or controlled with shutdown being initiated when connection to all specified computers is lost.

The license of this software is Freeware, you can free download and free use this automation software.