HDTenEightyP/NetNews huggingface dataset:
From: curts@mcrware.UUCP (Curt Schwaderer)
Subject: Re: Network Connections over ISDN
Organization: Microware Systems Corp., Des Moines, Iowa
Date: Fri, 14 Aug 1992 17:12:50 GMT

In article <1992Aug12.085917.5543@ericsson.se>, etxorst@eos.ericsson.se (Torsten Lif) writes:
|> In article 145@indyvax.iupui.edu, imhw400@indyvax.iupui.edu () writes:
|> >In article <1992Aug10.132038.26320@ericsson.se>, etxorst@eos.ericsson.se (Torsten Lif) writes:
|> >[...]
|> >> I'm more than just a little annoyed with how the marketing crowd make
|> >> broad statements about the D-channel capacity being 16 kbit/s without
|> >> ever mentioning how much of it is CONSTANTLY used by the traffic
|> >> overhead. The D-channel's primary function is to provide a signalling
|> >> path between the terminal(s) and CO. There exist signalling elements
|> >> for user-user communication but they are (at the best) of secondary
|> >> priority to the CO. Not that I dislike the idea of using the D-channel
|> >> for user-user data transfer, far from it, but it should be made
|> >> perfectly clear that this is not a high-speed/volume service.
|> >
|> >Okay, would you please help use newbies understand where this CONSTANT
|> >signalling traffic comes from on a subscriber loop.  What do the terminals
|> >have to discuss with the CO when they aren't setting up or tearing down calls?
|> 
|> When you put it that way - Good question!

There are a couple of messaging protocols at layer 2 going on excluding sending
call control packets for layer3.

There are timers involved at layer 2. If no messages have been received in a 
time period (usually ~20 sec), Layer 2 will send what is called an "S" frame to
the network (or vice versa) soliciting a response just to verify the link is
still up.

There are also TEI check and response messages that go on periodically that
the CO initiates to verify and maintain all of the endpoints of a given 
ISDN line. 

All in all, the messages that layer 2 sends over the line are pretty sparce.
The timer situation will only send messages on an idle line. The TEI check stuff
is only initiated when the CO hasn't heard from a TEI in a long time. So
layer 2 usually keeps the D channel pretty free.

-- 
+-----------------------------------------------------------------------+
| 	Curt Schwaderer, WAN engineer, Microware Systems Corp		|
| 		    Des Moines, Iowa 50325-7077				|
+-----------------------+-----------------------------------------------+
| curts@microware.com	| My statements may not be UNDERSTOOD BY, let 	|
| uunet!mcrware!curts	| alone REFLECT Microware's viewpoints.		|
| (515)224-1929 x388	| 						|
+-----------------------------------------------------------------------+
Newsgroups: comp.dcom.isdn
From: munro@ttd.teradyne.com (Peter Munro)
Subject: Re: TCP/IP via ISDN using PC ISDN card and packetdriver
Organization: Teradyne Inc., Telecommunications Division
Date: Fri, 14 Aug 92 16:40:15 GMT

In article <713484137snx@home.demon.co.uk>,
   cms@home.demon.co.uk (Cliff Stanford) writes:

> In article <stritzi.713190245@Physik.TU-Muenchen.DE> stritzi@Physik.TU-Muenchen.DE writes:
> 
>>I have an ISDN card in a 386/PC. The ISDN card manufacturer delivers it
>>with a packetdriver, so I can do TCP/IP using the packetdriver and
>>PC/TCP from FTP Software (slpdrv on top of isdnpkt).
> 
> 	I wish I could find such a card in the UK.  Does anyone know
> if such a thing exists?
> 		Regards,
> 			Cliff.

Try the ISDN DataVoice S0 PC Card,
from:
	Gravatom Technology Limited
	Fareham Heights
	Standard Way
	Fareham
	Hampshire
	ENGLAND
	PO16 8XT

	Tel: +44 329 825757
	Fax: +44 329 825457

We use this card, together with their TCP/IP Gateway for Unix software,
for routing TCP/IP between geographically distant locations (two TCP/IP
LANs).  The link is built on demand and cleared down after a presettable
inactivity timeout.  The link is rebuilt if data is then sent.  So rlogin,
ftp, telnet etc work transparently (& even NFS if you feel so inclined).
We use their Unix software, although I they supply PC drivers too.

Hope this helps.

Pete
----------
 Peter Munro
 Teradyne Telecommunications Limited
 The Western Centre, Western Road, Bracknell, Berkshire, ENGLAND, RG12 1RW
 Telephone  +44 344 426899
 Fax        +44 344 481355
 Mail       munro@teradyne.co.uk (or munro@uktera.uucp)
From: johng@informix.com (John Galloway)
Newsgroups: comp.dcom.isdn
Subject: wanted: articles/references on to the current # of ISDN users.
Date: 13 Aug 92 23:02:38 GMT
Organization: Galloway Research
Originator: johng@godzilla

Obviously what I really want is a good projection of what the
use WILL be over the next few years, but since I think that is
likely difficult to impossible, I'll settle for some estimate of
volume of the current use(s).   thanks.
	-jrg
internet    jrg@galloway.sj.ca.us  John R. Galloway, Jr  795 Beaver Creek Way
applelink   D3413                  CEO...receptionist    San Jose, CA   95133
                                   Galloway Research     (408) 259-2490
From: lars@spectrum.CMC.COM (Lars Poulsen)
Newsgroups: comp.dcom.isdn
Subject: Re: Is the hub end of ISDN just N * the user end?
Date: 20 Aug 92 23:33:02 GMT
Article-I.D.: spectrum.1992Aug20.233302.21574
Organization: CMC Network Systems (Rockwell DCD), Santa Barbara, CA, USA

In article <optere0@sgi.sgi.com> rpw3@sgi.com (Rob Warnock) writes:
>Ah, but the IECs (long-distance carriers) are racking up the bucks
>selling PRI as LEC bypass service...

How well does the LEC BRI interoperate with the IEC PRI service ?
And are they both National ISDN-1 profile ?
Newsgroups: comp.dcom.isdn
From: dror@digibd.com (Dror Kessler)
Subject: Re: Network Connections over ISDN
Organization: DigiBoard Incorporated, Eden Prairie, MN
Date: Fri, 14 Aug 1992 14:31:43 GMT

In article <1992Aug10.124544.24303@informix.com> johng@informix.com (John Galloway) writes:
>In article <o0jm4eo@rhyolite.wpd.sgi.com> vjs@rhyolite.wpd.sgi.com (Vernon Schryver) writes:
>>
>>Consider what would happen if you hooked up such a box to a home
>>ethernet, and then started a big file copy or other network application
>>that uses more than 64Kbit/sec between two of your home machines.  The
>>box would saturate the ISDN link back to the central site with packets
>>that should never leave the local network.
>>
>>The salesman said their box is intended only for people with single
>>machines at home.  All of the arm twisting and verbal abuse 3 of us
>>could apply in a small, private conference room was not enough to make
>>him admit that people might have real home ethernets.
>
>Note that while having a multi system home net may indeed not be uncommon,
>just having a single machine and a laser printer connected by ethernet
>offers this same problem, even more commonly if we're talking Appletalk<->isdn.

The problem both posters are noting can be easyly solved by using standard
MAC layer bridging technology. By implementing an adaptive MAC address
learning alorithm and having some sort of a CAM based MAC address filter,
a device can keep local traffic off the ISDN B channel(s). 

You would not want to put a traditional MAC bridge in your home. For one, 
you simply can't afford it. The ISDN interface is also missing in most
cases which further complicats matters.

Without getting too commercial, my company makes such a device (IMAC) that 
hooks up to ISDN and does exactly that (you can also afford it). I will email 
more information upon request.

----------------------------------------------------------------------------
Dror Kessler                                         phone: (612)943-5374
Senior Member of Technical Staff                     fax:   (612)943-0803
DigiBoard
6400 Flying Cloud Drive
Eden Prairie, MN 55344                               e-mail: dror@digibd.com
----------------------------------------------------------------------------
From: makyen@netcom.com (makyen)
Newsgroups: comp.dcom.isdn
Subject: Re: Network Connections over ISDN
Date: 19 Aug 92 10:41:43 GMT
Organization: Netcom - Online Communication Services  (408 241-9760 guest)

rick@digibd.com (Rick Richardson) writes:
>However, after accounting for flags, layer 2 and 3 headers, CRC bytes,
>and bit stuffing (about 1 bit stuffed in 32 for binary data), you come
>up with about 1+3+4+2+1 = 11 bytes of fixed overhead.  For packet
>length of 256, bit stuffing adds about 8 more bytes of overhead. So
>you only get 2000 cps * 256/(256+19) = 1860 cps.  For 512 byte packets,
>it works out to 2000 * 512/(512+27) = 1898 cps. At 1024, its 1918 cps.

>So 1024 byte packets on the D channel are approximately equal to a
>19,200 bps async "wire".  Smaller packets are very close to 19.2.
>Its so close, its not worth quibbling about.

>OOPS -- I forgot to add in the layer 1 overhead - you've got to
>wait 8-11 one bits between frames.  Add 1 to 1.5 bytes to the above
>numbers and recompute.  It won't make much difference.
Minor nit: that would be 10 and 11 one bits for data.  8 and 9 one bits
are for call management.  These alternate, so your average would be
10.5 bits/packet.

Also you have forgotten to take into account the packets that are
sent back and forth for call and line management.  These are,
at a minimum, some keep alive stuff, and various other goodies.

Thus you get an effective unidirectional bandwidth of significantly
less than 19.2Kbits/s.  However, it you should keep in mind that
most 19.2Kbaud modems do not provide 19.2Kbaud bidirectional.
Thus, as usual with these comparisons, your mileage may vary.


makyen@netcom.com
From: amigo@milton.u.washington.edu (The Friend)
Newsgroups: comp.dcom.isdn
Subject: ISDN - when for the average user?
Date: 21 Aug 92 21:11:39 GMT
Article-I.D.: milton.amigo.714431499
Distribution: na
Organization: University of Washington


	
	I'm interested in ISDN, but it seems the business community is
the main one getting to use it (of course its where the $'s are). I'm wondering
when an average home subscriber will be able to call their tel. Co. and
ask to get ISDN for a small extra charge? I'm on US West, which is fairly
busy in ISDN, but I doubt they'll have it for out-in-the-sticks locations
for at least a decade at the rate things are going..

						--> Mike
Newsgroups: comp.dcom.isdn
From: vjs@rhyolite.wpd.sgi.com (Vernon Schryver)
Subject: Re: Network Connections over ISDN
Organization: Silicon Graphics, Inc.  Mountain View, CA
Date: Fri, 14 Aug 1992 16:22:31 GMT

In article <1992Aug14.073757.25228@cbnewsd.cb.att.com>, varney@cbnewsd.cb.att.com (Al Varney) writes:
> ...
> >> >..., but some of use are interested in the bits/sec number because
> >> >we have concrete applications that need certain minimum rates.
> 
>    But what if the bit RATE is above the minimum, but there was
> an over-all 2 second latency in transmission?  Could an even
> higher speed compensate, or are there things (such a echoing of
> a typed character) where the bit rate is not critical, but the
> transmission delay is very important?

Agreed.  Latency is important.

Thank you very much for the numbers.   They are very interesting.

> ...
>     Telebit T2500 modems, 9600 baud using PEP, call across the room
> Procomm Plus(rg) window Kermit, 1 byte LRC, 1000 byte packet      755 CPS
> ...

>     PC-to-PC, 9600 baud to D-Channel
> Kermit (non-sliding window, 1000 byte packets)                    601 CPS
> Procom Plus vers. 1.1B, window Kermit, 1024 byte packets          725 CPS
> Procom Plus vers. 1.1B, Ymodem-G                                  940 CPS
> Procom Plus vers. 2, window Kermit, "relaxed timeouts"            930 CPS
> Procom Plus vers. 2, Zmodem streaming, "relaxed timeouts"         930 CPS


>     PC-to-PC, 19200 baud to D-Channel
> Kermit (non-sliding window, 1000 byte packets)                    960 CPS
> Procom Plus vers. 1.1B, window Kermit, 1024 byte packets          xxx CPS
>   {Unreliable, many time-outs, around 1133 CPS when it worked}
>   {Making EITHER to 9600 baud eliminated time-outs - about 750 CPS}
> Procom Plus vers. 1.1B, Ymodem-G                                  xxx CPS
>   {Unreliable, many time-outs, around 1190 CPS when it worked}
> Procom Plus vers. 2, window Kermit, "relaxed timeouts"           1333 CPS
> Procom Plus vers. 2, Zmodem streaming, "relaxed timeouts"        1240 CPS
>   {About 1 error per 10K bytes!!}


For comparison, UUCP file transfers over Telebit T2500's at 19.2 DTE on
with reasonable computers get 1300-1400 Bytes/sec net.

Good v.32bis/v.42/v.42bis modems (e.g. DSI 9624LE+) move at least 
1500 Bytes/sec through TCP/IP/SLIP.


>    I didn't measure latency directly....
>                              ...   So a total delay of around 70 msec.
> would be a good estimate.

Latency with v.32bis/v.42/v.42bis modems as measured by "ping" (ICMP
echos over IP/SLIP) are from 160 milliseconds to 300 ms depending on
the brand of modem.

I bet you'd be shocked and horrified by an external measure of latency
such as `ping` over ISDN.  I was when I looked at modems.


Is a fair summary that today ISDN D-channel appears to be faster than
PEP modems for some things but generally slower than v.32bis/v.42
modems?  So that ISDN D-channel might be good for intermittent stuff,
such as remote interactive access, where the packet charges might be
less than phone rates, but less good than a $430 v.32bis modem for
moving bulk data?


Vernon Schryver,  vjs@sgi.com
From: jeff@is.s.u-tokyo.ac.jp (Jeff McAffer)
Newsgroups: comp.dcom.isdn
Subject: Ok, so I'm a newbie
Date: 15 Aug 92 02:59:01 GMT
Reply-To: jeff@is.s.u-tokyo.ac.jp
Distribution: comp
Organization: Dept. of Infomation Science, University of Tokyo.


I am new to ISDN (gee, is there an echo on this newsgroup?) perhaps
there is a FAQ list I can read?  Much of the discussion here is
(hopefully) far more technical than I can or want to follow.  That's
fine, this is comp.dcom.isdn.  However, I have the following (simple?)
situation and am hoping that there is a simple solution someone can
tell me about.

I have an ISDN board for my SPARC and want to get one for my PC.  The
SPARC board is plugged into the phone jack.  I want to plug my PC
board into a phone jack in a different place.  We pay for telco time
by the minute so I would like to be able to do the 'disconnect while
idle' trick.  The goal is to run X using the FTP PCTCP transport.

Questions:

0) Is this hard?  Impossible?  Expensive?  Dumb?  Fast enough?

1) PC ISDN board manufacturer names?  I see people saying they have
them but no names!  Are there significant differences?

2) I heard a rumour about some part of 'the protocol' (no idea what
that means) being non-standard and varying between say a Sparc and
some other box.  Is this driver stuff?  Is this actually a problem for
what I want?

3) I have one ISDN board in the SPARC.  Can it reasonably suport two
concurrent connections?

4) What is this I see about 19.2K connections?  I thought all ISDN was
64K (or is it 57.6K).

5) If I can only get one physical line, do I need a special telephone
(for just normal voice) if it is an ISDN line?  Can I just plug a
normal phone into the ISDN line?

Thanks alot for your help.  Sorry for the beginner level of these
questions.  We all have to start somewhere.  This would be really cool
if I get it working.

--
atode, |m         -- Rockin' tunes empty my head and fill my soul!
                     Art!!  Is that you in there?!
Newsgroups: comp.dcom.isdn
From: rpw3@rigden.wpd.sgi.com (Rob Warnock)
Subject: Re: Is the hub end of ISDN just N * the user end?
Organization: Silicon Graphics, Inc.  Mountain View, CA
Date: Thu, 20 Aug 1992 04:53:10 GMT

lars@spectrum.CMC.COM (Lars Poulsen) writes:
+---------------
| Unfortunately, the RBOCs seem to roll out PRI offerings even slower
| than BRI offerings :-(
+---------------

Ah, but the IECs (long-distance carriers) are racking up the bucks
selling PRI as LEC bypass service...


-Rob

-----
Rob Warnock, MS-9U/510		rpw3@sgi.com
Silicon Graphics, Inc.		(415)390-1673
2011 N. Shoreline Blvd.
Mountain View, CA  94043

Newsgroups: comp.dcom.isdn
From: cms@home.demon.co.uk (Cliff Stanford)
Subject: TCP/IP via ISDN using PC ISDN card and packetdriver 
Distribution: world
Organization: Demon Systems Limited.
Date: Sun, 16 Aug 1992 10:42:03 +0000

In article <1992Aug14.114239.1@ttd.teradyne.com> munro@ttd.teradyne.com writes:
>
>Try the ISDN DataVoice S0 PC Card,
>from:
>        Gravatom Technology Limited

	1)  The MCA version is broken.  I am waiting for Gravatom to
let me have an updated version.
	2)  As far as I know, they do not have a packet driver for the
card.  The only MsDos software seems to be a file transfer package.
		Regards,
			Cliff.

-- 
Cliff Stanford                              cliff@demon.co.uk
Demon Internet Services			    cms@home.demon.co.uk
42 Hendon Lane				    +44 81 349 0063
London N3 1TT                               +44 860 375870
From: lidl@uunet.uu.net (Kurt J. Lidl)
Newsgroups: comp.dcom.isdn
Subject: ISDN products, ISA cards, etc
Date: 13 Aug 1992 18:20:43 -0400
Organization: AlterNet -- Falls Church, Virginia, USA
Distribution: world
NNTP-Posting-Host: rodan.uu.net

I'd like to gather a little information about the various ISDN
hardware products that are "out there", and summarize for the
net.

Let me make myself clear here -- I'm not interested in the
ISDN <-> ethernet bridge type of product.  Ideally, I'd like
to get enough info/pointers to put together a real snapshot of
where things are on two fronts:

1) ISA cards that plug into the telco:
	Is there a packet driver interface for the card?
	Is there a good set of technical docs, such that one
	could write a unix driver for the card?

2) Units with a V.35 connector that you can plug into either a
primary rate or BRI telco connector and shove IP at, given
reasonable router software.  (I want something that I can
configure to bring up a B channel and keep it up, assuming
that I can get unmetered service, either through a virtual
centrex or by using an off premise extension for passing
traffic.)

-Kurt
-- 
/* Kurt J. Lidl (lidl@uunet.uu.net)   | Unix is the answer, but only if you */
/*                                    | phrase the question very carefully. */
/* Don't even think of confusing my opinions with my employer's opinions!   */
Newsgroups: comp.dcom.isdn
From: varney@cbnewsd.cb.att.com (Al Varney)
Subject: Re: wanted: articles/references on to the current # of ISDN users.
Organization: AT&T Network System, Lisle, IL
Distribution: na
Date: Sat, 15 Aug 1992 01:56:11 GMT

In article <1992Aug13.230238.5992@informix.com> johng@informix.com (John Galloway) writes:
>Obviously what I really want is a good projection of what the
>use WILL be over the next few years, but since I think that is
>likely difficult to impossible, I'll settle for some estimate of
>volume of the current use(s).   thanks.


   How would you like both deployment plans, by NPA/NXX and "type"
of ISDN (ISDN-1 BRI, proprietary BRI, PRI) AND actual ISDN availability
data from 1991.

   How much would you pay?

   And if it included data not only from the RBOCs, but from Rochester Tel.,
Cincinnati Bell, AT&T and MCI?

   Now how much would you pay?

   Regardless, it will cost you $110 (+ sales tax).  Just call Bellcore
on 1-800-521-2673 and ask for:

  SR-NWT-002102, "ISDN Deployment Data", Issue 2.

  Good luck.
Newsgroups: comp.dcom.servers
From: dial109@titan.ucc.umass.edu (Siu-Ki Chan)
Subject: SLIP
Organization: University of Massachusetts, Amherst
Distribution: usa
Date: Tue, 18 Aug 1992 12:26:50 GMT

Sorry for what possibly might be a FAQ, but what is SLIP?
What can it do that other programs in the same cateogory can't?
Where can I obtain a copy of it?

Any feedback via email is greatly appreciated. Much thanks.

-SKC
From: lchiu@animal.gcs.co.nz (Laurence Chiu)
Newsgroups: comp.dcom.telecom
Subject: Re: 2500 Picturephone in the News
Date: 20 Aug 92 22:14:47 GMT
Organization: GCS Limited, Wellington, New Zealand
X-Submissions-To: telecom@eecs.nwu.edu
X-Administrivia-To: telecom-request@eecs.nwu.edu
X-Telecom-Digest: Volume 12, Issue 648, Message 3 of 10

In article <telecom12.647.9@eecs.nwu.edu> dave@pipi.iis.u-tokyo.ac.jp
(David Wuertele) writes:

> Mark Jenkins <Marcus@CPVA.SAIC.Com> writes:

>> In article <telecom12.638.3@eecs.nwu.edu>, jeffj@krf.com (Jeff
>> Jonas) writes:

>>> I wonder how long before 900 numbers offer video services?

>> Some of them already do.  West Coast Swingers, a California personals
>> magazine, has a 900 number with video phones. 

> This is a little off of the videotelephone question, but: Video
> Jukebox Network uses 900 numbers in conjunction with cable tv
> broadcast to allow subscribers to order music videos using a 900
> number.  Conceivably, other video services could be offered as well.

> What I want to know is how they make sure that only the person who
> dialed the 900 number gets the video?  Or do they just broadcast to
> everybody?

> [Moderator's Note: Much like in a restaurant when you put money in a
> jukebox everyone gets to listen whether they paid or not, the
> television version operates the same way.   PAT]

Is that true? This is kind of off topic now but I recall when I was
last in the US my friends had a cable channel which was pay for view.
You saw a preview of the movie you were about to see and if you wanted
to see if, you called some 800 number and they would unscramble that
movie for you.  So no one else who did not pay would not be able to
see it. Presumably the music video could be sent our scrambled and
they send down a signal to unlock your particular decoder only.


Laurence Chiu


[Moderator's Note: Yeah, but not true with the Jukebox Channel or
whatever it is called. I will defer to Bill Pfieffer here since he
knows more about the one in Chicago, but I think you 'put money in the
jukebox and make your selection' via a 900 number; eventually (a few
minutes or so later) whatever you selected is played.  If two or more
people selected the same thing, then like with a regular jukebox it
still plays one time and lets each paying party assume *they* are the
one who is paying. :) When (whatever you picked) is played, all
pending requests for the same song are cleared from the stack.  PAT]
Date: Mon, 17 Aug 92 11:03:22 MDT
From: jones@sunspot.sunspot.noao.edu (Wayne Jones)
Newsgroups: comp.dcom.telecom
Subject: Information Needed on Mitel SX-200
Organization: TELECOM Digest
X-Submissions-To: telecom@eecs.nwu.edu
X-Administrivia-To: telecom-request@eecs.nwu.edu
X-Telecom-Digest: Volume 12, Issue 639, Message 3 of 14

Rumor has it that we are going to replace our old AT&T Dimension 400
pbx with a Mitel SX-200.  Can any of you knowledgeable folks tell me
of your experiences with this system?  The boss is planning on sending
me to school to learn how to install, program and maintain this thing.
As a general electronics technician with some telephone experience how
should I expect this to go?  Will I be in over my head or what?  We
have about 120 phones and an attended console.  We're on top of a
mountain and the AT&T keeps getting wiped out by lightning.  Will this
system be any easier/cheaper to repair/protect?

Any information on the system, Mitel's school or anything else you
think I should know would be greatly appreciated.

Thanks in advance.


Wayne Jones    National Solar Observatory
P.O. Box 62    Sunspot, NM  88349   
505-434-7043   email:  jones@sunspot.noao.edu