RE: Going the distance
- To: "Cornejo, Edward (Edward)" <ecornejo@xxxxxxxxxx>
- Subject: RE: Going the distance
- From: Bruce_Tolley@xxxxxxxx
- Date: Thu, 1 Jul 1999 10:40:38 -0700
- cc: stds-802-3-hssg@xxxxxxxx
- Sender: owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
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
> >
>