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RE: Going the distance




I have no problem including 2km, 10km, and 40km. So I would support your
comments.

Ed-Lucent



> ----------
> From: 	Bruce_Tolley@xxxxxxxx[SMTP:Bruce_Tolley@xxxxxxxx]
> Sent: 	Thursday, July 01, 1999 1:40 PM
> To: 	Cornejo, Edward (Edward)
> Cc: 	stds-802-3-hssg@xxxxxxxx
> Subject: 	RE: Going the distance
> 
> 
> 
> Ed:
> 
> I would like to see the numbers go like this for SM fiber: 2, 10, and 40
> (if
> possible).
> 
> Bruce
> 
> 
> 
> 
> "Cornejo, Edward (Edward)" <ecornejo@xxxxxxxxxx> on 07/01/99 10:36:19 AM
> 
> Sent by:  "Cornejo, Edward (Edward)" <ecornejo@xxxxxxxxxx>
> 
> 
> To:   stds-802-3-hssg@xxxxxxxx
> cc:    (Bruce Tolley/HQ/3Com)
> Subject:  RE: Going the distance
> 
> 
> 
> 
> 
> Brian,
> 
> It seems that HP and Lucent have a general consensus on having an
> objective
> that lists two distance requirements for single mode fiber.
> 
> How does the rest of the committee feel about a 2km and 10km single mode
> fiber objectives? Is this something that has a possibility of >75%
> approval.
> 
> Ed-Lucent
> 
> 
> 
> > ----------
> > From:
> >
> BRIAN_LEMOFF@xxxxxxxxxxxxxxxxxxxxxxxxxx[SMTP:BRIAN_LEMOFF@HP-PaloAlto-om16
> > .om.hp.com]
> > Sent:   Thursday, July 01, 1999 12:33 PM
> > To:     Cornejo, Edward (Edward); stds-802-3-hssg@xxxxxxxx
> > Subject:     RE: Going the distance
> >
> >
> >      Ed,
> >
> >      I don't agree that the laser is always the "big ticket item in a
> >      transceiver".  This may be true in long-haul telecom (and it may be
> >      true for 10GbE serial), but in both 1000-SX and 1000-LX
> transceivers,
> >
> >      the laser (i.e. VCSEL or FP) accounts for a small fraction of the
> >      overall transceiver cost. It is by no means obvious that a serial
> 10G
> >
> >      FP transceiver, will cost less than a 4x2.5G WWDM transceiver.
> >      Regardless of this, I don't think it will hurt the process to have
> a
> >      2km objective in addition to a 10km objective.
> >
> >      -Brian Lemoff
> >       HP Labs
> >
> >
> > ______________________________ Reply Separator
> > _________________________________
> > Subject: RE: Going the distance
> > Author:  Non-HP-ecornejo (ecornejo@xxxxxxxxxx) at HP-PaloAlto,mimegw2
> > Date:    7/1/99 7:33 AM
> >
> >
> > I believe 2km over SMF will cover a majority of Campus LAN applications,
> > and
> > therefore a good place to start. I base the 2km distance on FDDI cabling
> > structure, GE survey presented by Chris D., and ISO's 2-3km spec.
> >
> > The serial proposal is two fold, one for shorter reach(2km), and one for
> > intermediate reach(15km). The 2km approach uses an uncooled unisolated
> > Fabry-Perot laser; this should be considerably less cost than 4 uncooled
> > unisolated DFBs(i.e. WWDM approach). I know there are other factors here
> > like packaging, and electronics, but I believe most folks would agree
> that
> > the laser is the biggest ticket item in a transceiver. If the minimum
> > distance is >2km, you will be excluding a potentially lower cost
> solution.
> > Unnecessarily IMHO because it covers a majority of your applications.
> >
> > For the same reasons I want 2km, I would not want to exclude anyone at
> the
> > longer distances. Therefore, I would support 2km, and 10km as the two
> > distances for SMF. Also, in my view the two distance proposals would be
> > the
> > same footprint and electrical interface to the PCS or MAC, so it is not
> a
> > major hassle having seperate laser spec's for the PMD.
> >
> > Going further distances beyond 10km, or 15km is never a problem; it is
> > just
> > how much customers are willing to pay.
> >
> > I concur with my colleague from HP that we should meet customer demands,
> > but
> > also consider technology capabilities and costs. Lets not be too
> exclusive
> > at this early juncture. It is always easier to increase our distances
> than
> > to throttle them back in case we run into unforseen problems with MMF or
> > SMF
> > at 10G.
> >
> > Ed-Lucent
> > > ----------
> > > From:
> > >
> >
> BRIAN_LEMOFF@xxxxxxxxxxxxxxxxxxxxxxxxxx[SMTP:BRIAN_LEMOFF@HP-PaloAlto-om16
> > > .om.hp.com]
> > > Sent:         Wednesday, June 30, 1999 7:36 PM
> > > To:   pbottorf@xxxxxxxxxxxxxxxxxx
> > > Cc:   Bruce_Tolley@xxxxxxxx; hfrazier@xxxxxxxxx;
> > > rtaborek@xxxxxxxxxxxxxxxx; stds-802-3-hssg@xxxxxxxx
> > > Subject:      Re: Going the distance
> > >
> > >
> > >      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
> > >
> >
> 
> 
> 
> 
>