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RE: Equalization and benefits of Parallel Optics.

I agree with you that the 300 m objective was put in place to address the
needs of building backbones. The many surveys of building cabling that have
been brought to the 802.3 all indicate that 300 m covers the vast majority
of building backbones. While we have no formal survey of equipment rooms,
300 m is probably overkill for this environment. 

My recollection of the main reason why the 300 m objective did not include
the word "installed" is that by omitting it we allowed ourselves the ability
to solve the problem with the greatest degree of freedom. We did not
restrict ourselves to finding a solution strictly for the installed base
because we wanted to be able to consider other alternatives that, while not
specifically supporting the installed base, allowed the continued use of
MMF. This is because MMF's ability to support legacy applications is highly
valued by our customers. Also, we were not sure if an attractive solution
for the installed base would come forward. 

At this point we have a proposed solution for the installed base in the form
of 1300 4-WDM. I believe this technology will work. I believe that the
market will use this solution. 

I also know that the market wants an alternative solution for situations
where the installation of new MMF results in an overall cost advantage for
the customer (the end user). Such installations certainly include new
construction, building refurbishment, equipment room rearrangements, and in
some cases upgrades to existing MMF infrastructure in building backbones.
Yes, it is true that some customers will upgrade existing MMF
infrastructures to SMF. The choice depends on many factors. 

Because it is not a simple black and white decision, there is not a simple
single answer. We need to recognize this situation and be responsive by
supplying the market with the solutions it wants. Not to do so is a foolish
business decision. Ethernet did not get to the top of the list by providing
high-cost solutions. Indeed, the success of Ethernet has everything to do
with providing the lowest cost solutions. Ignoring this proven formula for
success makes no sense. We need to embrace the advantages that the new MMF
can bring to Ethernet. Your customers and mine are telling us so.

Paul Kolesar

	From:  Bruce Tolley [SMTP:btolley@xxxxxxxxx]
	Sent:  Thursday, July 27, 2000 7:25 PM
	To:  Booth, Bradley; stds-802-3-hssg@xxxxxxxx
	Subject:  RE: Equalization and benefits of Parallel Optics.

	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
	up to the York meeting.

	My recollection from the York meeting is that we started discussing
	objective for 300 meters on installed fiber and ended up with
	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
	850 serial PMDs on new MM fiber.  Both sets of voters were thinking
	terms of building and campus backbones. The distance value of 300
	itself has always been justified on the basis that it covers some 
	substantial percentage of the installed base of building and campus



	At 02:35 PM 7/27/00 -0700, Booth, Bradley wrote:

	>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
	>optics/fiber for the 100m application, and I should have probably
	>my statement with that.
	>If it is only going to meet the 300m over MMF objective (and from
	>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
	>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
	>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.
	>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
	>                 Sent:   Thursday, July 27, 2000 3:34 PM
	>                 To:     Booth, Bradley; stds-802-3-hssg@xxxxxxxx
	>                 Subject:        RE: Equalization and benefits of
	>                 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
	>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,
	>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
	>                 >
	>                 >Cheers,
	>                 >Brad
	>                 >
	>                 >                 -----Original Message-----
	>                 >                 From:   ghiasi
	>                 >                 Sent:   Thursday, July 27, 2000
2:17 PM
	>                 >                 To:
	>                 >                 Cc:     Ali.Ghiasi@xxxxxxxxxxx
	>                 >                 Subject:        RE: Equalization
	>benefits of Parallel
	>                 >Optics.
	>                 >
	>                 >                 Brad
	>                 >
	>                 >                 > From: "Booth, Bradley"
	>                 >                 > To: stds-802-3-hssg@xxxxxxxx
	>                 >                 > Subject: RE: Equalization and
	>of Parallel Optics.
	>                 >                 > Date: Wed, 26 Jul 2000
18:29:56 -0700
	>                 >                 > MIME-Version: 1.0
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	>                 >                 >
	>                 >                 >
	>                 >                 > I have one question:
	>                 >                 >
	>                 >                 > Which of our distance
objectives is
	>satisfied with
	>                 >parallel fiber and
	>                 >                 > parallel optics?
	>                 >
	>                 >                 The 100 m data center
	>                 >                 >
	>                 >                 > 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
	>applications, where
	>                 >the fiber are not
	>                 >                 installed in the building
	>                 >
	>                 >                 Data center application are very
	>significant as stated in
	>                 >the last meeting
	>                 >                 about half the total market.
	>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
	>candidate for low cost
	>                 >data center
	>                 >                 applications by having cable
	>over parallell fiber.
	>                 >But you need
	>                 >                 to offset fiber advantage
against power,
	>size, cost,
	>                 >testing, and maturity.
	>                 >
	>                 >                 >
	>                 >                 > Or am I missing the point
	>                 >                 >
	>                 >                 > 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