How to talk to phones from linux

[bob at sinister.com (Bob Keyes)]

On Tue, 30 Dec 2003 nmeyers at javalinux.net wrote:

> On Tue, Dec 30, 2003 at 04:45:53PM +0000, John Chambers wrote:
> > The folks I'm working for have just come up with a  request
> > that  seems  to  be  difficult to find any real info about.
> > What they want to do is have their linux boxes (mostly  RH,
> > various  releases)  initiate  phone  calls,  and send voice
> > messages.  One example is:
>
> John,
>
> I think you just need a voice-capable modem - preferably an external
> one to avoid grappling with the WinModem issue. If I recall correctly,
> the commands to manipulate voice functions are "AT"-type commands
> extending the time-honored Hayes modem command set, and include support
> for recognizing touch-tone responses.

A voice capable modem is one way to solve it, but this depends on the
volume and application. Using a VOIP gatewa may be an easy and cheap way
to do this, and will save on long distance charges. If high quality speech
and many simulataneous calls are required, using a digital line such as
ISDN or T1 (ISDN BRI is 2 channels, ISDN PRI is 24 channels, T1 is 23
channels) may be called for.

Is this a one-off project, or something that will be a marketed product?
The proper approach depends greatly on how much resources can be put into
the design. If this is a one-off or you want to build a prototype, I have
some hardware (voice cards, etc for ISDN) that I would be able to sell
you.

But you'll have to assure me you're not doing voice-spam (telemarketing)
:)