From: cheim@lectroid.sw.stratus.com (Craig Heim)
Newsgroups: comp.dcom.telecom
Subject: Re: Stolen Cell Phone
Date: 15 Oct 92 13:26:03 GMT
Reply-To: somebody@somehost.edu
Organization: Stratus Computer Inc.
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X-Telecom-Digest: Volume 12, Issue 784, Message 4 of 10

In article <telecom12.779.5@eecs.nwu.edu>, ccoprfm@prism.gatech.edu
(Monte Freeman) writes:

> Over this past weekend, someone broke into my car. The two items they
> removed (they wanted the whole car, but the alarm system prevented
> them from getting that. ) were my OKI 700 cellular phone and a Yaesu
> FT-727 dual band hand-held ham radio.

> I realize that I'll probably never see the HT again; but I was
> wondering what you and/or the rest of the readers think my chances of
> getting the phone back are? I called Pactel and told them what had
> happened. They turned off service to the phone immediately.

> I've heard that there is a database of stolen phone ESNs that the
> different service providers keep. What I'm not sure about is if this
> database is local to each area, or if it's a nationwide thing ...

There are actually two "Nationwide Negative Files".  One was formed by
GTE Telecommunications Services (GTETS) that services *primarily* the
B-band carriers.  The other was formed by Appex (now EDS Personal
Communications Corporation) that services *primarily* the A-band
carriers.  There are other smaller services, but these two are the
real players.

In order for carriers to set up roaming agreements with other
carriers, it is a requirement to subscribe to a fraud protection
service.  GTE offers PVS (Positive Validation Service) and EDS PCC
offers PRV (Positive Roamer Validation).  Basically, these services
connect to each switch and listen for roamer calls.  Each roamer ESN
is checked against the Nationwide Negative File of invalid numbers.
If the number is negative, the verification service sends a command to
the switch which handled the call to bar that number.  Once a number
is barred on the switch, future calls are blocked (or even better,
routed to the carriers fraud control department).  Note that one
successful call was made before the shutdown occurred.  It is possible
for a bandit to traverse the country making one call at each switch.

There is a gateway between GTE and EDS PCC used to keep the Nationwide
Negative Files in sync.  If an A-band customer roams in a B-band-only
area, the validation service may validate the ESN.

> If I report a phone stolen here in Atlanta, are the cellular service
> providers in Chicago or L.A. likely to know about it?

Atlanta will inform the verification service of the stolen phone ESN.
That will result in an entry in the Nationwide Negative files.

> If the phone does show up "active" on a cell somewhere, is it possible
> (or more importantly is it done) to try and track it down?

There have been cases where the police/FBI tracked down drug dealers
using a device to locate the phone.  It is difficult, but possible.

Sorry, but I don't think the FBI is going to go after your particular
phone.


Craig R. Heim                 |Stratus Computer, Inc.  |My opinions are my own,
Software Engineer             |55 Fairbanks Blvd.      |not necessarily are
cheim@lectroid.sw.stratus.com |Marlboro, MA 01752-1298 |they Stratus's.