There are many reasons why you want to have remote access to a system.

Wake On Lan is a function developed by AMD back some years ago and implemented in most NICs available these days. My Intel Pro 100/1000 onboard adapter supports it and with my recent purchase (a OneClick ‘intelligent’ power extension block) it was provided the necessary ‘flea’ power so that it would be able to receive the packet. WOL is really easy if the machine you want to wake up is on the same IP subnet but what if the machine is only accessible through the Internet? Well that needn’t be a show stopper either

I use a D-Link DSL-504 router which is configured to use NAT so clearly I was gonna have to consider some form of port forwarding. Two things are an issue though. 1) most WOL utilities don’t do anything more than broadcast the magic packet on the same subset (not much good for Internet traffic!) and 2) the machine at the other end would be off and so the usual method of forwarding to its IP wouldn’t be much help.

Solution to #1 came in the shape of a tool called Wake On LAN GUI. A freeware tool that’s often referenced but seldom found for download.

Solution to #2 was to configure my router’s ARP cache to have a permanent entry for the machine’s IP to MAC address. That way the router just used the ARP cache blindly forwarding the magic packet to the required MAC address and hey presto - the machine powers up! Drop me a note of the forum if you’d like to know more details!