rsnider@nexus.yorku.ca (Richard Snider) (03/08/89)
One of the common ways that people acomplish phone fraud in apartment
buildings or (room above room above room) dorms is by simply taking
the cover off the box where the line comes into their room. In
many buildings, they have been constructed in such a way that all that
has been done is that conduit has been run between floors and the
wires pulled in from either the top or bottom of the building.
This makes setting up the phone system relativly simple for the
installers since they just tap off a pair on each floor when they
need one and if they need more they just find an unused pair and
tap it as well.
It is fairly obvious that anyone wanting to make fraudulent phone calls
need only to tap the pairs available untill they get a dial tone (or
conversation) and then call away. Getting access codes is simply a matter
of time (and listening on the line).
To check for this sort of thing happening, you can hook an LED in series
with a 4k or so resistor. Hook this across your pair in the direction
that makes the LED light up. When the phone is off hook (Anywhere, not
just in your room) the LED will go out. Of course if the little LED does
not gather enough attention, you can make something (or get someone to)
that hooks up to a desk lamp or other electrical appliance. So now,
if you are not using the phone and the light goes out, pick up the
reciver and see if there is a conversation going on, and if there is,
you have the option to be abusive, or to simply call up the Telco on
a friend's line and tell them what is going on. You also know that
it is someone living above or below you that is making the calls!
This all of course assumes that this is all happening within the building.
The light will behave the same way if someone was tapping into access points
outside the building as mentioned in other articles so this may be useful
even if the wiring is not the same as described.
Good luck
Richard Snider
Where: ..uunet!mnetor!yunexus!xrtll!rsnider Also: rsnider@xrtll.UUCP
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