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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@xxxxxxxxx]
> Sent: 	Thursday, July 01, 1999 2:01 PM
> To: 	'rtaborek@xxxxxxxxxxxxxxxx';
> BRIAN_LEMOFF@xxxxxxxxxxxxxxxxxxxxxxxxxx; 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@xxxxxxxxxxxxxxxx]
> Sent: Wednesday, June 30, 1999 5:15 PM
> To: BRIAN_LEMOFF@xxxxxxxxxxxxxxxxxxxxxxxxxx; 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@xxxxxxxxxxxxxxxxxxxxxxxxxx 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@xxxxxxxxxxxxxxxxxx) 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@xxxxxxxx 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
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > 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@xxxxxxxxxxxxxxxxxx
> 
> --
> 
> 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@xxxxxxxxxxxxxxxx
> 1029 Corporation Way              http://www.transcendata.com
> Palo Alto, CA 94303-4305    Alt email: rtaborek@xxxxxxxxxxxxx
>