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From: Archie Cobbs <archie@whistle.com>
Message-Id: <199702110645.WAA09047@bubba.whistle.com>
Subject: Re: Re(2): isdn cards
In-Reply-To: <m0vtqkA-0000EWC@hcswork.hcs.de> from Hellmuth Michaelis at "Feb 10, 97 09:05:42 am"
To: hm@hcs.de
Date: Mon, 10 Feb 1997 22:45:02 -0800 (PST)
Cc: smp@csn.net, Andrew.Gordon@net-tel.co.uk, hardware@freebsd.org,
        multimedia@freebsd.org
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> > Where could one find the protocal specs for "the D channel"?
> 
> I have no idea, ask your ISDN/Telephone company. For DSS1 the relevant 
> standards are I.430 (Layer 1), Q.920/Q.921 (Layer 2) and Q.930/Q.931/Q.932
> (Layer 3). They are sold by the ITU (www.itu.ch) but can also be found
> for much less money on the Infomagic "Standards CDROM".

The layer 3 protocol is where it's all at.. and the "right" protocol
differs depending on who made the switch (NorTel, AT&T, Siemens..)
The NI-1 "National ISDN 1" is supposed to be a "standard" that makes
the switch type a non-issue, and it almost does... that's the beauty
of ISDN -- there are so many to choose from... in the US, anyway.

There are companies that sell the ISDN protocol stack for tens of
thousands of dollars (more the reason to write a free version :-)

The NI-1 spec is available from Bellcore.

-Archie

___________________________________________________________________________
Archie Cobbs   *   Whistle Communications, Inc.  *   http://www.whistle.com