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From: john@zygot.ati.com (John Higdon)
Newsgroups: comp.dcom.telecom
Subject: Re: Modems and Phone Rates
Message-ID: <1857@accuvax.nwu.edu>
Date: 6 Dec 89 05:42:03 GMT
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X-Telecom-Digest: Volume 9, Issue 554, message 7 of 11


In article <1799@accuvax.nwu.edu>, ames!ultra!ted@uunet.uu.net (Ted 
Schroeder) writes:
 
> In this discussion nobody has mentioned the fact that modems place a
> continuous carrier on the line, unlike human voices that pause between
> sentences and words.  There is a form of compression called DSI (and
> there may be other forms also) that allow this "dead space" to be
> used.  You might put 12 calls on 8 lines and assume the "dead space"
> would allow you to compress bandwidth this way.  I know this is done
> quite frequently in fully digital private networks, but I don't know
> how the public networks work and whether they use this type of
> technology.

There are two major problems with this. Long distance companies rarely
do this anymore (it was too disconcerting to the customers) and local
telcos *NEVER* do this between local offices. And remember, it's the
local telcos that want to put the extra charges onto modem users.

The drift has been lost here. Every justification for discerning
between modems and the human voice would apply to LD carriers, not the
metallic circuit that runs between your PC and your local central
office. You already pay for long distance; is someone suggesting that
modem calls should be charged at a higher rate?

But the original question concerned whether lines used for modems
should have higher *local* charges applied across the board.
 
        John Higdon         |   P. O. Box 7648   |   +1 408 723 1395
    john@zygot.ati.com      | San Jose, CA 95150 |       M o o !