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RE: Equalization and benefits of Parallel Optics.




Bruce:

I'm not certain the entire group sees the 300 m objective in the same way. 
Since the 300 m is not installed fiber it can be argued that it is not an 
objective for a high percent of installed fiber runs. The committee decided 
to address only 100 m installed fiber. SAN applications might require runs 
longer than 100 m and therefore may be well served by 300 m.

I don't  want to argue in favor of parallel ribbon for SAN applications. 
Though parallel ribbon will be used for rack jumpers a single fiber 
solution is a much more desirable long term answer for SANs. I believe we 
should not standardize parallel ribbon, especially at 300 m, however a 300 
m serial MMF solution for SANs does seem appealing.

Cheers,

Paul

At 04:25 PM 7/27/2000 -0700, Bruce Tolley wrote:

>Paul and Brad:
>
>I do not think the 300 meter objective was written with computer rooms in 
>mind.  It was written with building and campus backbones in mind.
>
>This was the context of the discussion within the distance ad hoc leading 
>up to the York meeting.
>
>My recollection from the York meeting is that we started discussing an 
>objective for 300 meters on installed fiber and ended up with consensus 
>on  objective that omitted the word "installed. "
>
>At the time, it seemed to me to be a compromise between those who wanted 
>to support the installed base with 1300 WWDM and those who wanted to 
>support 850 serial PMDs on new MM fiber.  Both sets of voters were 
>thinking in terms of building and campus backbones. The distance value of 
>300 meters itself has always been justified on the basis that it covers 
>some substantial percentage of the installed base of building and campus 
>backbones.
>
>Yours
>
>Bruce
>
>At 02:35 PM 7/27/00 -0700, Booth, Bradley wrote:
>
>>Paul,
>>
>>Thanks for pointing that out.  I stand corrected.  The parallel optics and
>>parallel fiber could be applied to the 300m over MMF objective.  Although it
>>does meet that objective, the previous emails were targeting parallel
>>optics/fiber for the 100m application, and I should have probably qualified
>>my statement with that.
>>
>>If it is only going to meet the 300m over MMF objective (and from Pat
>>Gilliland's presentation, only on new high bandwidth MMF), then I have the
>>same problem with this solution as I do with the 850nm Serial PMD solution.
>>They may both be the lowest cost today, but they don't satisfy the 100m over
>>installed MMF objective.  Considering we have two PMDs that are under
>>consideration to meet both the 100m over installed MMF and 300m over MMF
>>objectives, I believe it would be in the Task Force's best interest to focus
>>on those solutions.  That is just my humble opinion.
>>
>>Cheers,
>>Brad
>>
>>Brad Booth
>>Intel LAN Access Division, Austin Design Center
>>bradley.booth@xxxxxxxxx <mailto:bradley.booth@xxxxxxxxx>
>>(512) 407-2135 office
>>(512) 589-4438 cellular
>>
>>
>>                 -----Original Message-----
>>                 From:   Paul Bottorff [mailto:pbottorf@xxxxxxxxxxxxxxxxxx]
>>                 Sent:   Thursday, July 27, 2000 3:34 PM
>>                 To:     Booth, Bradley; stds-802-3-hssg@xxxxxxxx
>>                 Subject:        RE: Equalization and benefits of Parallel
>>Optics.
>>
>>                 Brad:
>>
>>                 I also understand our objectives in the same way. We don't
>>have an
>>                 objective for 100 m computer room connections. It seems to
>>me the 300 m
>>                 objective was written for computer rooms. The 300 m over MMF
>>could be
>>                 applied to any fiber solution.
>>
>>                 Cheers,
>>
>>                 Paul
>>
>>                 At 12:55 PM 7/27/2000 -0700, Booth, Bradley wrote:
>>
>>                 >Ali,
>>                 >
>>                 > From my understanding of the objectives, the task force
>>doesn't have a
>>                 >distance objective of "100m data center applications."  We
>>do have an
>>                 >objective for 100m over installed MMF fiber.  That 100m
>>distance objective
>>                 >was chosen because it reflects what is used in the data
>>center applications.
>>                 >If the task force satisfies the objective (which is a
>>requirement for the
>>                 >task force to do), then we provide a solution for the
>>application.  The
>>                 >reverse is not true.  If task force satisfies the
>>application, then we don't
>>                 >meet our objectives.
>>                 >
>>                 >Given that the task force has to satisfy objectives first
>>and foremost, I
>>                 >believe that it is key that the task force focus on those
>>proposals that in
>>                 >some manner satisfy an objective.  As I see it, parallel
>>optics and parallel
>>                 >fiber do not satisfy any of our objectives; therefore, the
>>task force needs
>>                 >to work on the ones that will satisfy our objectives.
>>                 >
>>                 >Cheers,
>>                 >Brad
>>                 >
>>                 >                 -----Original Message-----
>>                 >                 From:   ghiasi
>>[mailto:Ali.Ghiasi@xxxxxxxxxxx]
>>                 >                 Sent:   Thursday, July 27, 2000 2:17 PM
>>                 >                 To:     stds-802-3-hssg@xxxxxxxx;
>>bradley.booth@xxxxxxxxx
>>                 >                 Cc:     Ali.Ghiasi@xxxxxxxxxxx
>>                 >                 Subject:        RE: Equalization and
>>benefits of Parallel
>>                 >Optics.
>>                 >
>>                 >                 Brad
>>                 >
>>                 >                 > From: "Booth, Bradley"
>><bradley.booth@xxxxxxxxx>
>>                 >                 > To: stds-802-3-hssg@xxxxxxxx
>>                 >                 > Subject: RE: Equalization and benefits
>>of Parallel Optics.
>>                 >                 > Date: Wed, 26 Jul 2000 18:29:56 -0700
>>                 >                 > MIME-Version: 1.0
>>                 >                 > X-Resent-To: Multiple Recipients
>>                 ><stds-802-3-hssg@xxxxxxxxxxxxxxxxxx>
>>                 >                 > X-Listname: stds-802-3-hssg
>>                 >                 > X-Info: [Un]Subscribe requests to
>>                 >majordomo@xxxxxxxxxxxxxxxxxx
>>                 >                 > X-Moderator-Address:
>>                 >stds-802-3-hssg-approval@xxxxxxxxxxxxxxxxxx
>>                 >                 >
>>                 >                 >
>>                 >                 > I have one question:
>>                 >                 >
>>                 >                 > Which of our distance objectives is
>>satisfied with
>>                 >parallel fiber and
>>                 >                 > parallel optics?
>>                 >
>>                 >                 The 100 m data center applications.
>>                 >                 >
>>                 >                 > It has been my interpretation that when
>>we talked about
>>                 >100m of installed
>>                 >                 > base of MMF, that we were referring to
>>the MMF fiber
>>                 >currently available for
>>                 >                 > use by 802.3z.  Parallel optics does not
>>operate over this
>>                 >installed base.
>>                 >
>>                 >                 You are correct parallel optics would not
>>operate over an
>>                 >installed two fiber
>>                 >                 plant.  Parallel optics would loose if you
>>go in to an
>>                 >installed fiber base.
>>                 >                 What I suggested was 100m data center
>>applications, where
>>                 >the fiber are not
>>                 >                 installed in the building wiring.
>>                 >
>>                 >                 Data center application are very
>>significant as stated in
>>                 >the last meeting
>>                 >                 about half the total market.  Solutions
>>significantly lower
>>                 >cost targeted
>>                 >                 for sub 100 m is needed, otherwise there
>>will several
>>                 >proprietary solutions.
>>                 >                 Parallel optics is the lowest cost, almost
>>mature after 3
>>                 >years, lowest power,
>>                 >                 and smallest foot print.  Parallel optics
>>is ideal to get
>>                 >bandwidth off the
>>                 >                 edge of your board.
>>                 >
>>                 >                 Serial 850 or CWDM 850 can be another
>>candidate for low cost
>>                 >data center
>>                 >                 applications by having cable advantage
>>over parallell fiber.
>>                 >But you need
>>                 >                 to offset fiber advantage against power,
>>size, cost,
>>                 >testing, and maturity.
>>                 >
>>                 >                 >
>>                 >                 > Or am I missing the point here?
>>                 >                 >
>>                 >                 > Cheers,
>>                 >                 > Brad
>>                 >
>>                 >                 Thanks,
>>                 >
>>                 >                 Ali Ghiasi
>>                 >                 Sun Microsystems
>>                 >
>>                 >                 >
>>                 >
>>
>>                 Paul A. Bottorff, Director Switching Architecture
>>                 Enterprise Solutions Technology Center
>>                 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

Paul A. Bottorff, Director Switching Architecture
Enterprise Solutions Technology Center
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