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Phone or Tracking Device?
Red Wolf writes "The first major commercial service that traces people's locations using their mobile phones -- mapAmobile -- is designed more to ease the minds of worried parents and suspicious bosses than to enable unauthorised spying."
I am more worried about the 2005 law that requires GPS/triangulation in all cell phones for 911 call locating. Here's a link to an article in Popular Science about China and how people were using their cell phones to find out which buildings were infected with SARS.
.02
People play a game where you "kill" a nearby person after you locate them using your cell phone equipped with GPS. Just what I want, ANYONE to be able to locate me on the street (opt-in service or not isn't my point).
The first major wave of location services could beam to the U.S. as early as Christmas, when 44 percent of the nation's 149.2 million cellphone subscribers are expected to be traceable, according to the research firm In-Stat/MDR.
No thanks, I would prefer to die after placing a call to 911 rather than have whoever decide that they want to track me via GPS/triangulation.
Live free or die.
Just my worthless
In many ways this is worse than Orwellian, because at least in Orwell's vision, you could still hide from the cameras or escape to places that didn't have cameras on them. With this device if you had it on (assuming it works as well as they claim (doubtful)) they could pinpoint your location all the time
Firstly this has been available for over 6 months and it works. Secondly the facility has to be enabled on the phone, and disabling is no more complex than a menu selection. Thirdly any cellular telephone will give away your location to anyone with even the most rudimentary equipment.
This system seems to be UK based. In UK, the digital cellular systems is GSM/PCS. GSM base stations have a theoretical maximum diameter of 35km (15-20 miles?). Since the 1999/2000 boom in subscriber quantity, most cells top out at 2-3km and can be as small as 100m (300 foot) in town centers. Also, cells usually are segmented into 3 slices of 120 degrees each, to maximize channel re-usage ability.
Another GSM feature is the "timing advance", which roughly indicates the distance of a mobile from its base station. It is necessary, because GSM is time multiplexed. A mobile is assigned a "time slot" for transmission. To avoid interference between mobiles that are far away from the base stations and those that are near, the far mobile sends its packet a little bit too early. It then travels a the speed that radio waves use to have and arrives dead-on its time slot. While "timing advance" is originally used only for this purpose, it obviously also is a good indication of where the mobile is.
The mobile knows all these values - each base station has a unique identifiyer, and the timing advance is measured every N seconds (which btw is the reason why GSM mobiles are spec'ed for travel speeds of 250km/h max).
The trace system basically "phones-home" this information, where the base station ID is looked up in a database to find out where the mobile is.
This is not new. Former Viag Interkom in Germany offered such a service, too. Once registered, you could look up the position of a mobile through an internet page. There's also a travel assistance service of D1 Telekom Germany, where you call in, hang up, the system traces your position, and sends a text message with traffic jam information etc (for your current position) to your mobile.
All these systems base on the same method of locating you, but are marketed differently.
But back on-topic: there is no GPS. As simple as that.
I spoke with a developer with a working system. The phone companies can (as in "do now") provide the location information, and security is provided through certificates. If, for the moment, you assume that certificates work, you get to control who gets to see your location information. You can hand it off to your friends or boss, and you can turn it off (stealth mode) at any time. I saw it working and it is pretty impressive (or scary for all the reasons already mentioned). Also, once the infastructure is in place (which it now is), it is trivial to implement.
Coercive permission and court warrants would get around perfect security (if such a thing existed).
However, my point is that the infastructure is in place right now (in US) and implementation is easy.