[comp.dcom.telecom] They

lairdb@crash.cts.com (Laird P. Broadfield) (01/11/91)

In <15879@accuvax.nwu.edu> forrette@cory.berkeley.edu (Steve Forrette)
writes:

> - Before someone else brings this up, here's something that came to
>mind that I don't think is a big deal, but I just know some will:
>"privacy."  Now, someone always knows what city I'm in if I bring my
>cellphone along.  Note that unlike the *18/*19 FMR of the "B"
>carriers, this new referral service happens automatically when you
>place your first call, and there's apparently no way to shut it off
>(except to leave call forwarding on before you leave (once they get it
>working properly, that is!), but then you have to pay their "No
>Vaseline" full airtime prices for forwarded calls :=( )

Actually, I had a thought a while back, when I was chatting with an
out- of-town friend who works for (a B carrier.)  We were chatting
about all of the smarts that's going on behind the scenes vis-a-vis
signal strength, cell handoff, software based "hysteriesis" to avoid
back-and-forth of calls at nearly equal strength, and so forth, when I
realized that it should be fairly trivial to derive location
information from all this.

Not only that, you don't have to even go off-hook, the switch can bang
your phone with an interrogate packet without you ever noticing.

Seemed to us that this made perfect sense, and his intuition said that
a 100-yard radius of uncertainty was a reasonable guess, assuming some
foreknowlege of signal propagation characteristics in the particular
area.

"Ha ha, forget what _city_ you're in, we know what _room_ you're in!!"

Does this theory fall apart anywhere?

(P.S. Can somebody mail me with the mfr. and model of the handheld
that has a _vibrate_ ringer?  None of the local outlets seem to have
heard about it.)


Laird P. Broadfield                       
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