Subj : Old Versus New - Way
To   : Dale Shipp
From : Bob Ackley
Date : Sun Aug 24 2008 06:31 am

Replying to a message of Dale Shipp to David Farr:

 DS>  -=> On 08-23-08  14:17,  David Farr <=-
 DS>  -=> spoke to Richard Webb about RE: Old Versus New - Ways <=-

 DF>> I See your located in Eads, TN so I know its long distance for you,
 DF>> (I'm in  North Charleston, SC), but I have Vonage for phone service
 DF>> so I have free  long distance, I just don't know what kind of speed
 DF>> we'll get over Vonage. Be  interesting to find out tho. 

 DS> I'm curious.  IIRC, Vonage is a voice over IP (VOIP) service, much
 DS> like Skype, Comcast web phone, Verizon web phone etc.  I also seem to
 DS> recall a statement that a normal dial-up modem will not work over
 DS> those types of service.  Is that correct?

I suspect it has to do with bandwidth.  The ordinary phone line was designed
to reliably pass frequencies in the normal voice range, very roughly 100 to 
about
5,000 hertz.  Modems exceed that top limit by quite a bit, but the system was
over-designed in the first place and can handle that, although I think dial-up
reached its physical limit with the 56KB connections.  The logical (VOIP)
connections don't have to and most likely don't pass more than the normal 
voice-range frequencies, so ordinary modems won't work properly, if at all.  
Plus, there's a whale
of a difference between physical and logical connections; with logical 
connections the
individual data packets have to be reassembled, in order, to effect the 
connection -
with voice connections this is easily possible, effecting a data connection is 
I guess
possible, but the connect speed is going to be terrible because of the lag.

That said, I read years ago that AT&T had developed technology that allows
the phone system to determine if a particular call is a voice or data call -
this having something to do with AT&T's multiplexing and compression 
technology that allows them to push ever more calls down the same set of
wires.

All of that said, Ray Gwinn developed a virtual modem in his SIO package for
OS/2.  It allowed you to 'dial' and connect to sites over the Internet, as far 
as
Binkley was concerned it was a dial-up connect, but it was in fact over the
Internet.  I don't know if that could be adapted to work with VOIP technology.

--- FleetStreet 1.19+
 * Origin: Bob's Boneyard, Emerson, Iowa (1:300/3)

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