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RE: Going the distance

I support Bruce's comments for extending intermediate link distances from 5
to 10KM. All current transceiver vendors making LX modules for gigabit speed
has product that supports 10km link distances. According to some of the
transceiver vendor I talked to confirmed that  majority of their volume is
for 10km LX part. I also know that majority of networking vendors only sale
LX parts that support 10km link distance. 10KM 1000Base-LX is de-facto
standard in the industry for Gigabit Ethernet.
I don't mind going with conservative objective, but should seriously
consider 10km support over single mode fiber for 10GB.

Bhavesh Patel
Extreme Networks.

-----Original Message-----
From: Ed Grivna [mailto:elg@xxxxxxxxxxx]
Sent: Wednesday, June 30, 1999 9:36 AM
To: rtaborek@xxxxxxxxxxxxxxxx; Bruce_Tolley@xxxxxxxx
Cc: hfrazier@xxxxxxxxx; stds-802-3-hssg@xxxxxxxx
Subject: Re: Going the distance

Bruce, while I do not dispute your facts, I do question your 
conclusion.  Just because some small part of the populace is doing
something does not necessarily require that it be standarized.

As is evident by the statement itself, for those small segments of 
the market that have needs beyond those that are standardized, there
are often low-cost avenues that they can persue to fill those needs.

The fact that they are using LX beyond the rated distances even
puts into question if what they have is really a 1000Base-LX link.
It may well be constructed with LX compatible components and be
running the proper protocols, but that doesn't necessarily make it
an LX link.

The requirements for the standards committee are to standarized those
areas of the technology where such effort would benefit the overall
user community, not 1 or 2 users or potential users.  Unless this
market segment can be quantified into a reasonable percentage of
the overall market, I question whether a standarization effort is

Are we talking 5%, 1%, 0.1%, or 0.001% of the market?   At some point
it is necessary to make a cut, and state that the user may create links
beyond these bounds, but that their implementation is beyond the scope
of the standard.

-Ed Grivna  

Bruce Tolley wrote:
> The point has been made before that today customers are already going 
> 5 to 10 Km with 1000BASE-LX.  There should be no debate that it is a 
> market requirement to go 5 to 10 km with 10 GbE.
> While I am willing to consider accepting  a conservative 2 to 3 km 
> goal as the official goal of the project,  we need to acknowledge 
> that this is a conservative goal and, as we get on with the work 
> of the project , we should investigate whether we can stretch this goal..
> Bruce Tolley
> 3Com Corporation
> Rich Taborek <rtaborek@xxxxxxxxxxxxxxxx> on 06/29/99 05:01:32 PM
> Please respond to rtaborek@xxxxxxxxxxxxxxxx
> Sent by:  Rich Taborek <rtaborek@xxxxxxxxxxxxxxxx>
> To:   Howard Frazier <hfrazier@xxxxxxxxx>, HSSG <stds-802-3-hssg@xxxxxxxx>
> cc:    (Bruce Tolley/HQ/3Com)
> Subject:  Re: Going the distance
> Howard,
> I will gladly accept your suggestion of removing the portion of the
> motion in parenthesis as a  friendly amendment post-haste given your
> support of this motion as a seconder.
> - Rich
> Howard Frazier wrote:
> > The more I think about it, the more I like the idea of adopting the
> > 802.3z link distance objectives for 10 Gig. We should remember that
> > we are still in the study group phase, trying to scope out a project.
> > We can always adjust the objectives later.
> >
> > Let me therefore state my support for Rich's proposed motion:
> >
> > > "Support the premises cabling plant distances as specified in
> > > ISO/IEC 11801"
> > >
> > > The distances supported in ISO/IEC 11801 are:
> > >
> > > 100 m for horizontal cabling (applicable to copper, MMF, SMF)
> > >
> > > 550 m for vertical cabling: (applicable to SMF and possibly MMF)
> > >
> > > 2-3 km for campus cabling: (applicable to SMF)
> >
> > Rich, I would encourage you to drop the parenthesis.
> >
> > If we adopt this objective, we can make progress on the rest of the
> > work we need to do as a study group.  As was demonstrated in 802.3z,
> > we will need to review the objectives periodically, and revise them
> > if there is consensus to do so.
> >
> > Howard Frazier
> > Cisco Sytems, Inc.
> -------------------------------------------------------------
> Richard Taborek Sr.    Tel: 650 210 8800 x101 or 408 370 9233
> Principal Architect         Fax: 650 940 1898 or 408 374 3645
> Transcendata, Inc.           Email: rtaborek@xxxxxxxxxxxxxxxx
> 1029 Corporation Way    
> Palo Alto, CA 94303-4305    Alt email: rtaborek@xxxxxxxxxxxxx