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This article was posted to the Usenet group alt.hackers in 1995; any technical information is probably outdated.

Re: Electronic Highway Signs, Q about VCL

Article: 7629 of alt.hackers
Newsgroups: alt.hackers
From: (Loki)
Subject: Re: Electronic Highway Signs, Q about VCL
Sender: (Loki)
Organization: The World Public Access Unix, Brookline, MA
Date: Fri, 7 Apr 1995 21:58:00 GMT
Approved: Choosy moms choose .GIF
Lines: 58
Status: RO (marlowe) wrote:

>The highway near my house in Houston has just installed those electronic
>highway signs that show up all over the country. To be precise, these are
>permanent, tall, and have bulbs as pixels.

>Still it has got me wondering, is there anyway to hack one of these? How
>are they programmed. Others in town have highway conditions on them.
>How to the official types communicate with the sign? Radio? Phone? Direct

Just recently (a couple of years ago, anyways) an acquaintance of mine
was war-dialing the 203 area code.  He came across the system that
controlled the State of Connecticut's highway condition signs.  It didn't
require a password, so he proceeded to change the message to something
of a personal nature to our then-governor (The same governor that
saddled us with a state-income tax, but I digress)...

The state discovered that the signs were changed, returned them to their
original messages, and waited for him to call back.  To make a long
story short, he called back, they traced his number, and he was
arrested.  He got community service, and the State got a lesson in
computer security.


I know it may seem lame, but does anyone remember the password to
install Nowhere Man's Virus Creation Laboratory?  Granted, the
program was written in 1992, but I'm still using an XT that was
built in the early '80s!


The place where I work at uses Intermec time clocks and badge-readers
for attendance punches.  For security reasons, the badges have a
visible-light blocking bar over the employee's barcode.  The readers
use an infrared laser to read the badges.

Since I was curious about what my barcode contained, I disconnected
a badge-reader from the time clock, and plugged it into a dumb-terminal.
I swiped my badge through the reader, and the raw-data dumped to the
screen.  I got the following:


Apparently, 2 signifies that the employee is hourly (salary starts
with 1), xxxxx is the employee's clock number, and 02 is a check
digit of some sort.

The barcode itself is printed in Code 39, so it would be relatively
simple to spoof other's badges using commercially available software
or barcode fonts.


(Wishing my provider wouldn't append a "Sender:" field)


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