From: rustman@netcom.com (Rusty H. Hodge)
Date: Mon, 27 Dec 93 16:57:18 PST
To: ravage@wixer.bga.com (Jim choate)
Subject: Re: Police RF Links
In-Reply-To: <9312231521.AA14185@wixer>
Message-ID: <199312280055.QAA04889@mail.netcom.com>
MIME-Version: 1.0
Content-Type: text/plain


Jim choate says...
> Since most police departments don't encrypt
> (or at least not strongly) their database searches from their in-car
> computers I can see a possible hole here. I really don't expect it to stay
> open very long however (a year or two at best).
> 
> I know such data can be accepted by a normal pc w/ a scanner and modem. It
> should not be much of a step to put a xmitter online and do some spoofing.

I think you will find that most modems will NOT demodulate this data, only
the simplest RF data links use modulation schemes compatible with standard
modems.  (For example, the RF Packet Data systems that are merely grown up
versions of the equipment sold to amateur radio operators that does use
modems that comply to CCITT or old Bell standards).

But most police departments that are using mobile data terminals are using
proprietary modulation schemes.  So you would have to determine what type of
systems are in use in the target area, and then obtain a compatible unit
with a spoofed unit identification.

Not that easy.  A lot harder than just monitoring these transmissions.

Check out a publication called "The SPEC-COM Journal", available at
Ham Radio stores near you, this is the definitive guide to different and
experimental modulation schemes that Hams are playing with.



-- 
Rusty H. Hodge, Cyberneticist  <rustman@netcom.com>