Mobile phone newbie - part 2

You can buy a Pay as you go phone. You have to "register" it but you can give blag info. To really remain secret you can register it via the providers website (e.g. Orange) and to ensure secrecy and non tracability do it from the likes of a library or cyber cafe so that even the IP address used (if recorded) is anonymous. You load the phone with air time by buying tokens over the counter at a supermarket. So yes, you can remain completely anon if you try and think ahead!

Theoretically a prepay bought with cash; the number, source of sale, and cell location for each call are recorded, but beyond that the trail goes cold.

Coda: Police have matched shop's cctv footage of the sale, to suspects under investigation. There are financial incentives....

In article , snipped-for-privacy@aol.comma wrote

The phone cannot be annonymous and all calls including specifically when the phone periodically registers with a base station are logged. If you use the phone whilst driving, your speed can be calculated.

However, there is no way to determine who is using the phone. But its details can be determined.

Unles you purchase using a bit of plastic.

Why do you want to be anonymous?

In article , kqr writes

I don't think so, how would that work??

If you use the phone whilst driving, your speed can be calculated.

I don't know about that, but your mobile may be able to help you avoid a speeding ticket

I think it could be possible.

AIUI it is possible for the distance from a base transceiver station to a mobile to be measured by virtue of the timings of the signals. A mobile, in operation can be scanning for up to 16 base stations to look for one having better signal strength for a possible handover. That information is sent to the base station controller and mobile switching center to use in deciding whether to handove the mobile to another cell.

Given timing information related to multiple cells, it should be possible to compute the position of the mobile and any movement.

GPS does both with remarkable accuracy for example.

.andy

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In article , Andy Hall writes

GPS has much higher positional resolution though. I don't think there is sufficient resolution available from the GSM system. I have seen it quoted as 100 metres at best, which wouldn't be good enough for measuring movement speed with any worthwhile accuracy.

Unless it showed you were at place A +- 100m at 12:00 and at place B +-

Although I suppose you'd just claim that your phone had been cloned.

Neil

I agree otherwise Garmin wouldn't bother to make a device that uses both GPS and GSM

If you were travelling at 100mph for 1 minute you'd go about 2680meters

If the tolerances of the system were +- 100m then the furthest you could possibly have travelled would be 2880m and the shortest 2480m.

This equates to speeds of 107 mph and 92 mph which is only 8% and probably enough to prosecute you

Nick Brooks

Yes, but it is 100m "at best", presumably in cities where there are lots of base stations. I think you would need to be registering with at least

As long as they could prove who was driving at the time.... ;)

David

Assuming that the target was driving, two base stations would be sufficient if only one of the loci coincided with a road. In any case, if handguns are readily available, anonymised cell 'phones shouldn't provide an insuperable hurdle to someone with a criminal intent. You only have to look at how various partisan groups operated in WWII to see how it is possible to be difficult to detect.

John Schmitt

Don't forget that the purpose of this is to provide the user with positional information. Anything that could be determined from GSM would provide information to the network operator and others.

Until Clinton turned off selective availability with GPS, the accuracy of that for plebs was only around 100-200m.

.andy

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When I got my prepay O2 mobile 18 months ago it worked out of the box without registering anything. Registering it gave extra free credit, but wasn't needed to make the phone work.

since they determined that drivers who install the systems actually end up driving more slowly and safely than before. If such systems lead to safer driving, then I'm all for them.

Christian.

.. In the vicinity of speed cameras