From: bcapps@atlastele.com (Brent Capps)
Subject: Re: The ISDN network
Organization: Atlas Telecom Inc.
Date: Tue, 15 Dec 1992 17:43:27 GMT

In a previous article deej@cbnewsf.cb.att.com (david.g.lewis) writes:
[who would want to use it?]
>To start with, the people who have a need to communicate with the .003% who
>also have ISDN, and want the benefits of ISDN.

I'm talking about generalized calling situations in which you don't
know in advance who the calling/called party are.  The .003% you're
talking about represent closed user groups. 

Stewart Alsop has an interesting column in the Dec. 14 Info World wrt
Japan's aggressive ISDN deployment strategy:
   "When we asked what someone might use the ISDN pay phone for, though,
    she was stumped, because ISDN is not useful unless you know that
    you have it available from one end to the other.  The truth is,
    of course, that ISDN is great in theory but doesn't do anybody any
    good until everybody has it.  And Japan isn't ahead of the United
    States in figuring out what to use it for.  So the fact that the best
    use of the digital pay phone is for the analog modem jack is indicative
    of the problem..."

>> If I have an ISDN box that automatically delivers fax or ASCII 
>>messages it's going to have a hell of a time determining on a per-call basis
>>whether to deliver a message via analog or digital form.
>
>1. It could maintain a customer database with subscription information,
>indicating whether the customer prefers G3Fax, G4Fax, text (and what
>format), etc.

The subscriber is the originator, not the terminator.  The application is
fax/ASCII broadcast.  I don't know in advance what kind of equipment is at the 
destination.  The only assumption I can make is if I'm trying to deliver a 
TIFF file, the terminating DN must be a fax machine.  I don't even know if 
it's G3 or G4, though with the miniscule number of G4 machines in the 
world I can venture a pretty good guess.  In practice all G4 fax manufacturers 
are backwards compatible with G3 anyway, so most users are going to say 
"my fax number is so and so".  Then the issue becomes, is that number ISDN 
or POTS?  In practice you're always going to use POTS except in those rare 
instances when you happen to know in advance that the terminating CPE is 
ISDN ready.  In this case ISDN belongs more to the problem set than the 
solution set as you bend over backwards to make it compatible with the 
existing PSTN.  This technology is the wave of the future?  Not!

>2. It could use a multiple-call method, first attempting a 64UDI call, and
>if that is cleared by the network or the called customer, reattempting using
>3.1kHz audio.

Be serious.  Given the low number of successful terminations ISDN is 
going to achieve, you've effectively doubled the user's phone bill.  
These are very big systems with phone bills in the hundreds of 
thousands per month.  More likely we'll try POTS first, and if we 
can't connect that way we'll punt and point the finger at the terminating 
equipment.  Sooner or later they'll get the message that ISDN is costing 
them more trouble than it's worth and go back to POTS.

-- 
Brent Capps                          | 
bcapps@agora.rain.com (gay stuff)    | Quis corriget correctores ipsos?
bcapps@atlastele.com (telecom stuff) |