Path: utzoo!utgpu!watmath!iuvax!rutgers!dptg!mtunh!mkd
From: mkd@mtunh.ATT.COM (Mark Darby)
Newsgroups: comp.dcom.lans
Subject: Re: Twisted Pair Ether query
Message-ID: <692@mtunh.ATT.COM>
Date: 9 Aug 89 17:40:42 GMT
References: <507@oblio.UUCP> <2230020@hprnd.HP.COM>
Organization: AT&T ISL Middletown NJ USA
Lines: 95

In article <2230020@hprnd.HP.COM>, craig@hprnd.HP.COM (Craig Blackwood) writes:
> > We are looking for experiences / impressions of running twisted-pair
> > ethernet.
> 
> I think it is great!  The diskless workstation from which I am writing this 
> is connected to the server via Twisted Pair ethernet (HP StarLAN 10).  With 
> other types of cable (thick and thin coax) one person can mess up the whole
> network simply by messing with the cable.  With StarLAN 10 other users can
> do whatever they want to the twisted pair that runs to their machine without
> causing any problems for others.

This is true for a standalone TPE (twisted pair ethernet) network, but
with the proper equipment, one can expand an already existing Ethernet/
Cheapernet network with StarLAN 10, providing cost effective expansion
without losing the original network investment.

As a footnote, AT&T's TPE solution is also called "StarLAN 10".

> 
> > Last time I looked at this stuff it was all in the talking stage -
> > nobody had any commercial hardware.
> 
> The product is a reality. The standard is almost a reality. The IEEE standard
> is called 10baseT and (from what I know :-) will be official near the beginning
> of next year.
> 

10BASE-T is a task force under the auspices of IEEE 802.3, drafting a 
standard for 10Mb/s baseband transmission over twisted pair wire. The 
10BASE-T draft was recently voted upon by IEEE 802.3 voting members and
failed by a significant margin (75% ratio of yes votes to yes+no votes is
required for approval, actual ratio obtained was about 59%). Over 600
comments were received from voters which must be addressed, however
most of these were editorial comments and general specmanship issues.

As a matter of fact, the 10BASE-T task force is meeting this entire week
in San Jose, California to address voter comments and issues.

The new schedule of target dates for 10BASE-T includes a second letter ballot
for the end of this year, with the presenting of voting results to IEEE 802.3
by March 1990. Assuming no delays in the entire schedule, including
submitting draft to the IEEE Computer Society and IEEE review board, the
draft could be sent to ANSI for submission to ISO by 4Q90. This assumes
all submissions will result in approvals every step of the way. 
Any disapproval along the way could delay the progress of the draft further.

> > Now I understand Cabletron makes some
> > equipment, and there are presumably others.  I wasn't paying any attention
> > before, but now we about to move and looking at cabling options for cubicles,
> > especially for use with our X terminals.
> 
> HP makes twisted pair ethernet products (called StarLAN 10) including PC LAN
> cards, HUBS, minicomputer and Workstation interface cards.
> AT&T and Synoptics also make StarLAN 10 products.  There are probably many
> others.

AT&T, HP and Ungermann-Bass currently make TPE hardware products which comply
with key technical parameters of the 10BASE-T draft, including transmit 
voltage levels, transmit equalization, 100m distance support per twisted pair
link, and the use of a multiport repeater (ala IEEE 802.3) as the HUB element.
Because of this, the current hardware from these vendors INTEROPERATE, which
is what standards are all about.

SynOptics' TPE solution is called "Lattisnet." 
They have made some new product announcements, and I do not
know if their new products take any more 10BASE-T parameters into consideration.
I do know that previous products (with some exceptions) from Lattisnet took
very few key 10BASE-T parameters into consideration.

As the 10BASE-T draft becomes more a reality,
each vendor will have a migration path from current product to final
"10BASE-T" product. Those vendors who have proprietary solutions to TPE
will a more difficult migration path to follow, depending upon how much
the vendor has veered from the path followed by 10BASE-T. 

> > 
> > I have a notion this has been discussed here before and I missed it (hey, I
> > don't have time to read everything); if so, I think I would appreciate mail
> > rather than followups.
> > 
> > Mats Wichmann
> > Acer America
> > hplabs!oblio!mats
> > ----------
> 
> Craig Blackwood
> craig@hprnd.rose.hp.com

Let me know if I can be of further assistance.

------------------------------------------------------------------
Mark K. Darby
AT&T Bell Laboratories                       AT&T: (201)957-2706
200 Laurel Ave.                              uucp:..!att!mtunh!mkd
Middletown, NJ 07748