| Petar
I agree 4x25G will be lower cost than 10x10G because of all the reason you stated, fewer components and fiber counts. My point was 10x10G cost is at least an oder of magnitude higher than 10Gbase-SR since you have 10x the components and therefore its cost too high as base for comparison with 100G-SR4.
If we can't reduce cost/gigabit with higher speed PMDs that interface will not achieve broad market potential!
Thanks, Ali
On Feb 3, 2012, at 9:29 AM, Petar Pepeljugoski wrote: Hi Ali,
I agree with you. We need to find the
proper comparison. For one, I think the lowest cost at one time was 4GFC,
(although today, per gigabit its cost is too high relative to some other
solutions that appeared recently).
I also agree with Dan Dove that the
10x perfromancce 3x cost model does not hold any more, at least in the
environment I am interested in. I can't imagine the 4x25G solution to be
more expensive than 10x10. If it is, we are doing something wrong. By all
accounts, it should cost less (smaller number of components, smaller footprint,
smaller number of fibers in the MMF cable). In my opinion (I know some
people will disagree), proper comparison is with 4x10.
If we develop standard around that cost
model, I believe people will start developing custom solutions that address
their cost targets. This will further fragment the market and increase
the cost for the standard.
Regards,
Peter
Petar Pepeljugoski
IBM Research
P.O.Box 218 (mail)
1101 Kitchawan Road, Rte. 134 (shipping)
Yorktown Heights, NY 10598
e-mail: petarp@xxxxxxxxxx
phone: (914)-945-3761
fax: (914)-945-4134
From:
Ali Ghiasi <aghiasi@xxxxxxxxxxxx>
To:
STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Date:
02/03/2012 12:10 PM
Subject:
Re: [802.3_100GNGOPTX]
Minutes Uploaded - Forward Direction
Paul/Dan
My concern by using 100Gbase-SR10 which is high cost we
are creating too low a bar. The situation is even
worse if you look at 100G-LR4 with its astronomical cost!
I prefer still for any cost comparison to go to 10Gbase-SR/LR
something were its cost close to earth than moon.
Thanks,
Ali
On Feb 3, 2012, at 6:03 AM, Kolesar, Paul wrote:
All,
I struggled with the cost basis
question while I prepared my contribution to the just-past meeting. I
considered using either 10GBASE-SR or 100GBASE-SR10 as the basis. In
reviewing contributions on transceivers (a.k.a. PMDs) I noticed that there
was a tendency to use 100GBASE-SR10. So to make it straight forward
I decided to also use 100GBASE-SR10 as the cost basis for the cabling cost
analysis portion of the Solution Set Analyzer called “Kolesar Kalculator
2012_01_25” in the tools folder on our web site. This spreadsheet
analysis tool allows one to get a complete channel cost analysis that includes
the transceiver modules and the cabling that connects them. See
http://grouper.ieee.org/groups/802/3/100GNGOPTX/public/tools/index.html
Therefore, to use this tool
to get a complete cost comparison, the cost basis comparison of transceiver
modules must also be entered relative to 100GBASE-SR10.
I offer this tool as a means
to get various cost projections on the same playing field. My rationale
is that using a common analysis tool will remove some of the variability
factors that cloud the cost picture. This should allow us to make more
confident and less contentious decisions regarding reach objectives that
often contain significant consideration of the trade-off between reach
and cost.
The analysis that I included
at the end of my user’s-guide contribution “Solution Set Analyzer Update
(revised)”
http://grouper.ieee.org/groups/802/3/100GNGOPTX/public/jan12/kolesar_01a_0112_NG100GOPTX.pdf
indicates that the optimal
reach objective for a possible future 100GBASE-SR4 is heavily dependent
on the cost of the single-mode transceivers that will be needed to satisfy
channel lengths that exceed -SR4 capability. I stressed this point
at the conclusion of my presentation, and I bring it up here again, because
the structure of the ad-hocs mentioned by Dan compartmentalizes and separates
the MM from the SM studies. While this seems like a natural and traditional
organization structure, and there is overlap among those involved, I would
like all involved to keep this fact in mind: These are not independent
silos. They are highly interdependent parts of the whole data center
ecosystem and must be treated that way in order to arrive at an optimal
solution set.
So I encourage folks in both
ad-hocs to apply the Solution Set Analyzer to sets of PMDs (both MM and
SM) that are needed to provide complete data center channel coverage. With
sufficient cross-pollination between the ad-hocs, each should be able to
keep informed of the other’s relevant contributions in a timely way.
Regards,
Paul
From: Daniel Dove [mailto:ddove@xxxxxxx]
Sent: Thursday, February 02, 2012 10:41 PM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] Minutes Uploaded - Forward Direction
Hi Ali,
I don't think the 10x vs 3x model applies to new PMDs for a given speed.
What is important is that we believe we can achieve Broad Market Potential,
Economic Feasibility, and Technical Feasibility for any particular objective
we produce. (assuming distinct identity and compatibility are met)
First, we need to convince ourselves of this. Then, we need to convince
802.3 and the SEC.
Dan
On 2/2/12 8:33 PM, Ali Ghiasi wrote:
Dan
We can go with 100GBase-SR10 cost
if its cost has reach traditional Ethernet cost which is 10x BW 3X the
cost.
Otherwise it would be better to
go back to the basic 100G-SR4 should be 3x the cost of 10GBase-SR
and the new SMF PMD should be 3x
the cost of 10Gbase-LR.
I expect both 100Gbase-SR10 and
100Gbase-LR4 would fail above criteria!
Thanks,
Ali
On Feb 2, 2012, at 4:49 PM, Daniel
Dove wrote:
Participants,
I should mention that my suggestion below to use 100GBASE-SR10 for relative
cost is not mandatory. It was a suggestion and should be considered as
one possible approach to relative cost assessment for SR4.
For an SMF objective, the ad hoc should decide what it wishes to use for
relative cost assessment if anything.
In theory, having a common point for relative cost assessment is not required.
Each presenter can provide their best judgment, explain how they came to
it, and let the group determine whether they are accurate. This approach
is also acceptable.
Regards,
Dan Dove
On 2/2/12 2:43 PM, Daniel Dove wrote:
Dear Study Group Participants,
The draft minutes have been uploaded to our website at http://www.ieee802.org/3/100GNGOPTX/public/index.html.
Please take a moment to review and feedback any items to Kapil Shrikhande
our vice-chair.
For those who attended the Study Group meeting in Newport Beach, you are
aware that we ended without a wrap-up due to a call for adjournment, second
and lacking opposition, we adjourned. At the time, I felt it would be better
to gather our thoughts and focus on how to move forward.
For those who did not attend, we were able to secure another objective,
"Define
re-timed 4-lane 100G PMA to PMA electrical interfaces for chip to chip
and chip to module applications".
In addition, we saw many presentations related to study for MMF and SMF
objectives.
We ran a few straw-polls and essentially the outcome was that we have additional
work to come to consensus on either a SMF or MMF objective. In addition,
guidance was provided through the straw-polling,
but it may not have been specific to making progress as a team. Rather,
it was oriented towards the type of material we would like to see. So,
below I will address a proposal for making forward progress using the information
gleaned from our meeting.
Adhocs:
Multi-Mode ad hoc led by Jonathan King.
Single-Mode ad hoc led by Pete Anslow.
These two groups will solicit participation and meet via teleconference
to:
1. Identify
a straw-man objective that can gain consensus
2. Identify
specific media/reach, market potential related to that reach based on relative
cost to SR10, technical feasibility
3. Identify
presentation material that they believe will convince the SG their objective
is valid.
We need to avoid getting into "baseline
proposal mode" where we see our preferred alternative competing with
the other alternatives. The goal of SG presentations should not be not
to sell a proposal. They should be focused on demonstrating an objective
meets the 5 criteria with multiple approaches.
If these two groups can pull together a compelling set of objectives, and
presentations that demonstrate they meet the 5 criteria, we can then come
together in March and work to identify any remaining consensus opportunities
that can be worked on for the upcoming May meeting.
Presuming we can finalize our objectives, 5 criteria responses, and get
our PAR completed in May, we will be ready to pre-submit and move toward
a July PAR submittal.
Best Regards,
Dan Dove
Chair, IEEE 802.3 Next Generation Optical Ethernet Study Group
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