Re: Position escrow

["Marty Levy" <rwww60@email.sps.mot.com>]

> I think you guys are worried about the wrong problem.
>
> The E911 stuff is still years off. Even when it is deployed, it will
> probably work only during a call, though this may depend on the exact
> method.
>
> In my opinion, idle cell registrations -- which are already standard
> cellular system practice -- represent the far more serious privacy
> threat.
>

It's worse than you think.  Most cellular base stations serve 7 cells,
and each cell uses receive diversity (mutiple antennas for the same
cell).  There is also a designed overlap of the cells from basestation
to basestation, otherwise you get blackout spots.  Although the
effort to use this information to locate a certain phone (provided
the power is on) is not trivial, the hardware is all in place.  Right
now, the basestation must determine which cell the user is in, but
the capability exists for it to narrow down the location and send
that information back to the network.  It probably won't (easily)
have the resolution of GPS, but once you know that much, you
can just home in on the phone's signal.