“Allowing desktop machines to go to sleep when idle is an obvious way to save power, but it comes at a price: sleeping machines can’t have patches rolled out, can’t serve up files, and can’t offer Remote Desktop connections. Wake-on-LAN (WoL) gives the ability to wake sleeping machines remotely, but isn’t integrated into existing software: a Remote Desktop connection to a machine that’s powered off will simply fail, rather than attempt to wake the machine first.
Microsoft Research’s Sleep Proxy provides a solution. A network agent intercepts traffic intended for sleeping machines, and if it determines that the machine needs to be woken up to respond to the traffic, wakes up the sleeping machine with WoL. This allows machines to be put to sleep aggressively, while keeping them accessible when necessary. The power savings on offer can be as high as 60-80 percent.”
Read the rest of the article here: ArsTechnica