2007-03-25

Skyhook wireless: pushing the envelope

Recently Skyhook Wireless, a startup company in Boston, has been in the news.

Basically, they are trying to sell positioning services-- the ability to wirelessly locate where you are at any time. Although you may think that the Global Positioning System has already solved this problem, GPS is somewhat inaccurate by itself. If you know the relative location of some other fixed points in your environment, it can boost accuracy greatly. Also, GPS reception may be spotty in some urban environments due to physical obstacles.

So far, so good. If we have marker beacons around the city, we can sell people the ability to localize themselves with great accuracy. But deploying those markers would take lots and lots of money... unless... they could use beacons already deployed. Like peoples' wireless routers.

What skyhook has done is to make a database mapping wireless BSSIDs to locations. BSSIDs are unique IDs stamped into wireless routers, comparable to the MAC addresses found on ethernet adaptors. They are hiring drivers to cruise around cities mapping out where all of the wireless routers are.

Whether or not this is a privacy invasion depends on whom you talk to. Personally, I think it's kind of scary to have that database around-- if nothing else, it could be used by router manufacturers to track down where their customers were. Although this may not seem like a big deal, it's kind of annoying. It used to be voluntary to send in that little "customer survey" card with your address! I bet governments would love to have access to this database too, although they have plenty of other ways to track people.

Contrary to what some Chicken Littles at Slashdot think, this database will not make it easier to trace IP addresses back to locations. The SSID gets stripped out of the packet before the destination computer ever see it.

Perhaps a little argument by analogy is in order here. Nobody expects the outside of their house to be private. Everyone can see what color you paint your house, and what kind of decorations you have in your lawn, etc. But when men in vans drive around your neighborhood periodically taking pictures of everything, it starts to raise a lot of questions. A lot of implicit assumptions of privacy have been violated.

I wonder who Skyhook's customers would be. Presumably the same people who care about GPS... businesses doing inventory tracking, people using automatic map systems in their cars...

Well, as I said earlier, this sort of thing is probably inevitable. To quote Issac Asimov in "The Dead Past": "Happy goldfish bowl, to you, me, and everyone."