cell phone anonymity

[Ray Dillinger]

This pretty much kiboshes the idea that they might be continuously 
broadcasting; I'm more concerned about the idea that there may be 
some signal they're passively listening for, to which they will 
*respond* with a pulse signalling their location. 

			Bear



On Mon, 8 Jan 2001, Phillip H. Zakas wrote:

>Hi,
>
>I don't believe cell phones can be queried while they're off.  The phone has
>to xmit a pulse (to hear a pulse, crank up your PC speakers, turn on your
>cell phone and place it within 3 inces of a speaker...you'll hear the
>speakers produce static at a regular interval [about every 30 seconds or so
>with my startac]).  In an unscientific study, I've placed my cell phone,
>turned off, next to the speakers and not heard the familiar pulse.  Also
>since you posed the question I ripped open my recently acquired Motorolla
>Timeport.  Not seeing any activity in the xmit circuitry when the battery is
>plugged in and the power is turned off.  Of course I'm having trouble
>putting the case back on the phone correctly but I'll figure that out later
>;)
>
>phillip zakas
>
>
>
>
>-----Original Message-----
>X-Loop: openpgp.net
>From: Ray Dillinger [mailto:bear at sonic.net]
>Sent: Monday, January 08, 2001 11:10 AM
>To: Phillip Zakas
>Cc: Multiple recipients of list
>Subject: RE: cell phone anonymity
>
>
>
>
>On Mon, 8 Jan 2001, Phillip Zakas wrote:
>
>>
>>Just a minor correction to the below posting: cell phone locations are NOT
>>calculated using GPS.  They're triangulated via the three nearest cell
>sites
>>reading the cell phone signal.  Accuracy is much lower than with GPS, but
>>good enough for cops to, say, find a stranded motorist on a highway.  I
>>believe resolution is somewhere around 40 meters in densely populated areas
>>(where there are many cell phone towers).  This resolution figure varies
>>from region to region.
>>
>
>Hm.  Okay.  I knew there were locators in them, and had assumed that
>they were GPS.  My mistake.
>
>Does anyone know any particulars about whether these phones can be
>queried for their locations while not in use?
>
>
>>IMHO, the real privacy issue with cell phones is the security of a
>>conversation.
>
>Yes indeed.  Privacy is a tougher thing to achieve than anonymity,
>at least with cell phones.
>
>				Bear
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