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Re: Going the distance




Bruce,

Your percentage (30%) rings a bell here, and we are insisting that LX
transceivers be qualified for 10 km for EVERYTHING in the enterprise space;
most vendors seem to be offering that as standard anyway now.

Larry Miller
Nortel Networks

At 05:02 PM 6/30/99 -0700, Bruce_Tolley@xxxxxxxx wrote:
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>Les and Ed:
>
>We might be able to estimate the potential size of the 5 to 10 km application
>segment by looking at shipments of LX ports today if the transceiver vendors
>have the data and are willing to share it.
>
>But more important than the mix of LX to SX ports  is the fact that many
>customers today  have a requirement to go these kind of distances. The
number of
>LX ports sold might be small compared to SX but this kind of application is
>pulling a lot of GbE business.  If you want me to quantify it, I'd say of the
>last ten customers I have been in meetings with, 3 of them were looking to
use
>the 10 km LX solution to go 5 to 10 km.
>
>Also I am not all that comfortable with the unstated assumption in much of
the
>previous debate that the short distances are in fact the major market for 10
>GbE.  The logical application for 10GbE in the LAN and Campus is to aggregate
>lots of GbE segments, which means between buildings and between rather large
>capacity switches that could be a long way apart (shall we call it a MAN?).
>
>Bruce Tolley
>3Com Corporation
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>Les Poltrack <lap@xxxxxxxxx> on 06/30/99 12:54:03 PM
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>Sent by:  Les Poltrack <lap@xxxxxxxxx>
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>To:   Ed Grivna <elg@xxxxxxxxxxx>, rtaborek@xxxxxxxxxxxxxxxx, Bruce
>      Tolley/HQ/3Com
>cc:   hfrazier@xxxxxxxxx, stds-802-3-hssg@xxxxxxxx
>Subject:  Re: Going the distance
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>Ed, you raise a good point and I wish I could answer with an
>absolute percentage on the requirement.
>
>There was another point raised that this might be more of a
>marketing question than anything else.  For what it's worth,
>my subjective marketing perspective, based on talking to
>hundreds of users about Gigabit Ethernet and their expectations
>for Ethernet backbone technologies, is that Bruce Tolley's
>suggestion of 5 to 10 km is right on the mark.
>
>I don't have the incontrovertible quantitative data I'd like to
>have on the distribution of distances required, but I would say
>that a good point was raised earlier that the fact that most
>long wavelength Gigabit Ethernet devices support 10km has
>created somewhat of an expectation for backbone distances
>in customer's mind and support of 10km by 10 Gigabit Ethernet
>devices would materially enhance the adoption of the technology.
>
>My two cents is that 10km is the right goal for a volume singlemode
>high speed backbone technology.
>
>Thanks,
>
>Les Poltrack
>Cisco Systems, Inc.
>
>At 11:35 AM 6/30/99 -0500, Ed Grivna wrote:
>>
>>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
>>appropriate.
>>
>>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              http://www.transcendata.com
>>> Palo Alto, CA 94303-4305    Alt email: rtaborek@xxxxxxxxxxxxx
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
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