Re: Modem Security

Date: 06/13/02

Date: Thu, 13 Jun 2002 10:15:07 +1200 (NZST)
From: <>

> Well, here's an idea. It depends on the type of phone system you have
> and whether or not your user needs inbound dialing. Most phone systems
> are PBX types that are pretty configurable. Make the modem line an

PABX or not, most teleco's will let you do call-diversion to another line
or have some kind of answering service. If inbound calls never go to that
line, you can be fairly confident that the modem won't be answering them.

It shouldn't really be a problem in the first place; check that the modem
isn't answering calls (by calling it) which is normally the default
behaviour. If it is, switch the feature off and beat the errant user with
a clue-by-four. Divert all incomming calls elsewhere just to be sure.

Presumably outbound calls are direct to the legacy service and not using
TCP/IP in any way (otherwise your user could presumably contact the same
service via the internet) so shouldn't present any risk.

One other thing to be aware of; there are a few 'dialler' programs out
there that will phone Muldovia when you're not watching, any machine with
a modem in it could be at risk. If your PABX allows it restrict outgoing
calls on that extension as far as possible just in case.

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