Is Barry Home?
Tracking Barry's location in real time

This idea popped into my head when I saw an illustration at The Annotated Weekender. I wondered how easy it would be to setup a site where you can check, in real-time, if Barry is at home.

As it turned out this was quite simple, I created a PHP script on a home server to track the list of connected devices on our home router. Checking the client names and MAC addresses of these devices I could determine if Barry had his phone or laptop on at home.

This PHP script is polled when a user visits the site to check in real-time if any of Barry's devices at home are active. Obviously this is not fool-proof, if Barry leaves his laptop on and is not at home, or if he is home with no devices on (rarer still!), then the results will be inaccurate. Some extra fiddling with the PHP script polling the router adds in tracking of how confident we are the result is correct. If confidence in the data is low then rather than saying for certain Barry is at home the site just says 'Not Sure'.

Update: Barry has since moved out, in no part due to this invasion of privacy. So the site is now stuck returning 'Not Sure', at least until I can come up with more nefarious means to track Barry's location.


July 2011