views:

271

answers:

2

I have just been to http://www.wikitude.me/

How does the site know the location of my laptop within 100 meters?? There is no GPS or anything that can give my location away on my laptop!

+6  A: 

It's something called geo-ip lookup. Your IP address is mapped out somewhere (probably stored in a database). This method is reasonably accurate, though not perfectly so.

More here: http://en.wikipedia.org/wiki/Geoip

JasCav
Right, you can take a look to the online demo of one of the leader of geoip application services there: http://www.maxmind.com/app/locate_ip
Boris Guéry
@bgy the http://www.maxmind.com/app/locate_ip gives the address as far as 6 miles away.I guess wikitude uses a similar database but probably more accurate.
ToughPal
While IP geolocation is part of the process, this is far from the whole truth. See my answer.
bjarkef
@Toughpal unless you on mobile it will give the address of your ISP. Sometimes it gives the address of your ISP's HQ in another city!
Martin Beckett
+1  A: 

Wikitude.me uses location aware browsing. Basically it tries to pinpoint your location using various available information such as you IP and the available access points your laptop is receiving beacons from. It can actually be very precise, there is a cool example on the information page at the above link.

The database is run by Google and is called Google Location Services. API here. The Android cell phones uses the same service to determine their position when the GPS is turned off, this time by available access points and cellular towers. And when the GPS is turned on, they of cause help update Googles database. :)

bjarkef