Re: Going the distance
- To: BRIAN_LEMOFF@xxxxxxxxxxxxxxxxxxxxxxxxxx, HSSG <stds-802-3-hssg@xxxxxxxx>
- Subject: Re: Going the distance
- From: Rich Taborek <rtaborek@xxxxxxxxxxxxxxxx>
- Date: Wed, 30 Jun 1999 17:14:39 -0700
- Organization: Transcendata, Inc.
- References: <H00008250f051d62@MHS>
- Reply-To: rtaborek@xxxxxxxxxxxxxxxx
- Sender: owner-stds-802-3-hssg@xxxxxxxxxxxxxxxxxx
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