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RE: Going the distance




I haven't read the text of 11801 on this, and might be missing something as
a result, but there is nothing in the motions that says MMF or SMF for the
specified distances.  I havent read it as necessarily implying two MMF
distances, nor do I see it as requiring three PHYs.  If two PHYs
appropriately satisify the three distances, all we need to define is two
PHYs.

I hope you noted, that my motion that will come from the table only has one
MMF distance and one SMF distance, and as I stated there, I expected the
list of PHY family members to grow.  I think it is better if we can agree to
objectives similar to the motion on the table (I agree with Johnathan's note
on the subject), and would only support the more generic objectives if we
are deadlocked (so we can move get a PAR).  I expect the generic objectives
would then later be replaced with more specific distance/media type
objectives.

--Bob Grow

-----Original Message-----
From: Cornejo, Edward (Edward) [mailto:ecornejo@lucent.com]
Sent: Thursday, July 01, 1999 11:38 AM
To: HSSG
Subject: RE: Going the distance



Bob,

Why is it okay to have two MMF distance. Is it because there are two
applications. If so, then I would argue that there are at least two for SMF
in the LAN environment. One for 2km, and one for ~10km or more.

Ed-LU

> ----------
> From: 	Grow, Bob[SMTP:bob.grow@intel.com]
> Sent: 	Thursday, July 01, 1999 2:01 PM
> To: 	'rtaborek@transcendata.com';
> BRIAN_LEMOFF@HP-PaloAlto-om16.om.hp.com; HSSG
> Subject: 	RE: Going the distance
> 
> 
> Rich:
> 
> I am in support of your compromise if with some discussion the Study Group
> appears as deadlocked as the Ad Hoc is.  To expedite matters, you should
> phrase your motion as an objective, not as guidelines for defining an
> objective. (We would still have to vote on the objective after voting on
> the
> motion you outline below.)  The third distance should only include one
> length.
> 
> Move to adopt as an HSSG objective:
> 
> x. Support premises cabling plant distances as specified in ISO/IEC 11801
> 	a. 100 m for horizontal cabling
>       b. 550 m for vertical cabling
>       c. 3 km for campus cabling
> 
> --Bob Grow
> 
> -----Original Message-----
> From: Rich Taborek [mailto:rtaborek@transcendata.com]
> Sent: Wednesday, June 30, 1999 5:15 PM
> To: BRIAN_LEMOFF@HP-PaloAlto-om16.om.hp.com; HSSG
> Subject: Re: Going the distance
> 
> 
> 
> Brian,
> 
> Please keep in mind that my proposed motion to use ISO/IEC premises
> cabling
> standards is based on our inability to overwhelmingly agree (75%) to
> distance
> objectives. Our best attempts at a motion failed in Coeur d'Alene. The
> distance ad
> hoc has reached no better consensus, and I'm afraid that Jonathan
> Thatcher's
> proposed process is too convoluted to set clear objectives. I'm araid that
> blending
> in the myriad market requirements for 10 GbE, 1 GbE specifications for a
> specific
> fiber type, requirements from 1 GbE links which greatly exceed the
> standard
> and use
> non standard (enhanced) cable and/or components, and the capabilities of
> any
> proposed 10 GbE schemes serve only to make any specific distance decisions
> harder to
> make and attain the concensus of 75% of the group. Remember also that
> we're
> a study
> group, and that you'll get your change to get your specific 'better'
> distance into
> the standard when we actually have a standards project to get it into.
> 
> As an individual straw poll, would you as an individual IEEE voter, vote
> against the
> following motion, if made?
> 
>    That the distance objective 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
>       550 m for vertical cabling
>       2-3 km for campus cabling
> 
> It is assumed that the 10 GbE standard will exceed these objectives quite
> handily as
> was the case for GbE.
> 
> --
> 
> BRIAN_LEMOFF@HP-PaloAlto-om16.om.hp.com wrote:
> 
> >      Paul:
> >
> >      I believe that the WWDM approach that we have presented, when used
> >      with uncooled, unisolated, reduced spec (on SMSR, linearity, RIN)
> DFBs
> >      will cost equal or less than the serial 10G FP laser approach that
> >      Lucent has proposed for 2km, and significantly less than the
> isolated
> >      DFB approach that they have proposed for 15km.  This would support
> >      ~300m on 62.5 micron fiber, and ~10km on SMF.  To push this
> approach
> >      to 15km may involve tightening the SMSR or RIN spec which will
> >      significantly increase the cost (since much of the low-cost nature
> of
> >      the approach depends upon using low-cost DFBs).
> >
> >      I realize that there is an ongoing debate about relative cost, but
> it
> >      would be a shame to set the objectives at 2km and 15km, when there
> is
> >      a potentially very low-cost solution that can go 10km. I have no
> >      problem with a 2km and 10km objective, since I believe we can
> satisfy
> >      both with a single cost-competitive solution.
> >
> >      I realize that Rich Taborek and others have criticized PMD
> suppliers
> >      (such as HP and Lucent) on this reflector for suggesting
> objectives,
> >      based on what each of our solutions can handle, but I don't think
> we
> >      can afford to ignore it either.  I don't deny that I favor 300m on
> >      installed base MMF and 10km on SMF in large part because that is
> what
> >      our WWDM module can support.  I have no problem backing off on
> these
> >      (say to 200m and 5km) if it allows alternative PMDs to be
> considered.
> >      Lucent wants 2km (not 3km) to be an objective so that their serial
> FP
> >      laser module is not excluded.  I'd like 10km (and not 15km) for the
> >      same reason (although I believe we're still competitive at 2km).
> >
> >      Distance objectives should reflect what the customers need, but
> should
> >      be influenced by what the available technologies can achieve.
> >
> >      -Brian Lemoff
> >       HP Labs
> >
> >
> >
> >
> >
> >
> > ______________________________ Reply Separator
> _________________________________
> > Subject: Re: Going the distance
> > Author:  Non-HP-pbottorf (pbottorf@nortelnetworks.com) at
> HP-PaloAlto,mimegw2
> > Date:    6/30/99 3:24 PM
> >
> > Bruce:
> >
> > I support your outlook. We already have 5-10 km with gigabit. Supporting
> > these distances is necessary to support the installed base. Since the
> > technology cut-off point is around 20 km and since a standard MAN
> distance
> > is 15 km I'd prefer a slightly more aggressive objective of 15 km. This
> > would still give reasonable design margin. I also believe lower cost
> > technology exits below 2.5 km motivating a 2 km specification. We could
> > either specify a single 15 km objective which covers all the
> applications
> > with a higher component cost or 2 km and 15 km each with a different
> price
> > point.
> >
> > I would like to see further extension into the MAN. GigE is selling day
> > with reaches over 50 km. The next standard distance is 40 km. I've heard
> > this distance was chosen to match the spacing of microwave towers. With
> the
> > 40 km distance I believe we would have all that is necessary to build
> Metro
> > networks.
> >
> > The three standard distances on SMF would be 2, 15, and 40 km. Each of
> > these ranges I believe falls into a different technology with a
> different
> > price point. If anyone has a technology which can do all three at the 2
> km
> > price then all the better.
> >
> > Paul
> >
> > At 09:13 AM 6/30/99 -0700, Bruce_Tolley@3com.com 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@transcendata.com> on 06/29/99 05:01:32 PM
> > >
> > >Please respond to rtaborek@transcendata.com
> > >
> > >Sent by:  Rich Taborek <rtaborek@transcendata.com>
> > >
> > >
> > >To:   Howard Frazier <hfrazier@cisco.com>, HSSG
> <stds-802-3-hssg@ieee.org>
> > >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@transcendata.com
> > >1029 Corporation Way              http://www.transcendata.com
> > >Palo Alto, CA 94303-4305    Alt email: rtaborek@earthlink.net
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > Paul A. Bottorff, Director Switching Architecture
> > Bay Architecture Laboratory
> > Nortel Networks, Inc.
> > 4401 Great America Parkway
> > Santa Clara, CA 95052-8185
> > Tel: 408 495 3365 Fax: 408 495 1299 ESN: 265 3365
> > email: pbottorf@NortelNetworks.com
> 
> --
> 
> Best Regards,
> Rich
> 
> -------------------------------------------------------------
> 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@transcendata.com
> 1029 Corporation Way              http://www.transcendata.com
> Palo Alto, CA 94303-4305    Alt email: rtaborek@earthlink.net
>