Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!sdd.hp.com!spool.mu.edu!uunet!cbmvax!drysdale
From: drysdale@cbmvax.commodore.com (Scott Drysdale)
Newsgroups: comp.sys.amiga.datacomm
Subject: Re: 19200bps
Keywords: 19200 bps
Message-ID: <21354@cbmvax.commodore.com>
Date: 7 May 91 19:04:09 GMT
References: <1991May5.185645.12902@cunixf.cc.columbia.edu> <1991May5.201708.452@cec1.wustl.edu> <1492@caslon.cs.arizona.edu> <48579@ut-emx.uucp>
Reply-To: drysdale@cbmvax.commodore.com (Scott Drysdale)
Organization: Commodore, West Chester, PA
Lines: 56

In article <48579@ut-emx.uucp> lshaw@ccwf.cc.utexas.edu (logan shaw) writes:
>In article <1492@caslon.cs.arizona.edu> dave@cs.arizona.edu (Dave Schaumann) writes:
>>There are already 38K baud connections (direct connect).  I believe that a
>>normal phone line is physically incapable of carrying more than a few thousand
>>baud at best, due to bandwidth limitations.  Perhaps when optical connections
>>become commonplace, the phone companies will be able to afford to consider
>>restructuring the phone transmission protocols, perhaps selling wider-band
>>width lines at a premium rate.
>
>I believe Northern Telecom phone switches already support digital
>modems.  (Northern Telecom supplies telecommunications hardware to
>both MCI and US Sprint).  In the long-distance telecommuncations
>industry, most everything is already all-digital.  The problem is
>essentially the local service and the wire in your house.
>
>>But until the phone companies see this as a paying proposition, I doubt
>>it will happen.
>
>Ah, they do, especially if one phone company has it and another doesn't.
>The problem is that it's an *extremely* expensive proposition that
>involves replacing all the wires that the phone network consists of
>with fiber.  That takes a _long_ time, and _alot_ of money.

that's not really true.  ISDN is one local office to customer site digital
solution.  it works on your existing wiring, and provides two bidirectional
64Kbps channels, and a 2kbps signaling channel.  this allows 8khz 8-bit
sampled voice on two lines.  the big problem ISDN faces presently is the
high cost of the customer's equipment.  is everyone willing and able to
replace all their phones (which cost around $25 nowadays) with $200 phones?

ISDN is running in many test installations and lots of corporate locations.
many modern pbx'es are actually small ISDN switches.

i want ISDN for the 64K "baud" bidirectional serial connection (of course,
hooking this up to your serial port is not going to work.  you'll need a little
box (which perhaps sits on a SCSI bus or a special plug in card)).  some of
the ISDN phones available have "modems" built in, but they can only talk to
other ISDN phones.  there are also DSP solutions that are compatible with
existing analog modems.  but all this costs money, there is no real standard
(many companies make ISDN switches, very few can talk to each other), and
people aren't exactly clamoring for it.

ISDN - I Still Don't Know
       I Smell Dollars Now
       Innovations Subscribers Don't Need (my favorite)

>  -Logan

  --Scotty
-- 
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Scott Drysdale           Software Engineer
Commodore Amiga Inc.     UUCP {allegra|burdvax|rutgers|ihnp4}!cbmvax!drysdale
		         PHONE - yes.
"Have you hugged your hog today?"
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