Buckinghamshire CC ANPR cameras

Mark Lomas ukcrypto at absent-minded.com
Wed Jan 11 08:27:02 GMT 2012

The authorities can deduce useful information about such phones without
traffic analysis.

I remember a police officer explaining the investigation of a kidnapping.
The kidnappers used a PAYG phone that was only switched on while making
ransom calls, never used to call any other phones, and taken to a new
location each time it was used. Consequently neither an intercept nor
traffic analysis would reveal information the police didn't already have.

Instead the police took the lists of all other phones in the same cells at
the times of the calls (the data James mentioned) and looked for phones
that were nearby on more than one occasion.


On 10 January 2012 21:52, Derek Fawcus <dfawcus+lists-ukcrypto at employees.org
> wrote:

> On Tue, Jan 10, 2012 at 02:14:37PM -0000, James Firth wrote:
> >
> > However, if you also have a mobile phone in your pocket (or many built
> in to
> > your car) your movements are already tracked and stored as required under
> > the data retention directive.
> An unregistered PAYG phone.  The phone is tracked,  but who is the owner?
> Yeah - they could to traffic analysis on calls to give hints as to owner.
> .pdf
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