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Re: [802.3BA] Discussion on 40G for => 10 km SMF

Title: RE: [802.3BA] Discussion on 40G for => 10 km SMF

Hello Takai-san,


You are probably busy in catching up on many items after your vacation, however could you kindly clarify exactly what is the reference for your 4x CWDM cost floor and 2x Serial floor projections in your Aug 16 email? This way we can continue the 40GE 10km SMF PMD discussion without any ambiguity as to your assumptions.


My assumption is that you were making apples to apples comparison, and in both cases intended as reference the cost of 10GE LR XFP decreasing year to year. If you used a different reference, for example 2010 10GE LR XFP cost for the 40GE Serial cost floor, it would be good to clarify that.

Thank you




From: Chris Cole
Sent: Monday, August 18, 2008 12:25 PM
To: 'STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx'
Subject: RE: [802.3BA] Discussion on 40G for ="" 10 km SMF



There continues to be confusion as to what cost multipliers (like 4x and 2x in your email) are referenced to. There are at least three possibilities:


  1. 2008 10GE LR XFP cost, as used for all cost multipliers in cole_04_0708, i.e. costs for all years are referenced to constant 2008 10GE LR cost
  2. 2010 10GE LR XFP cost, as used for all cost multipliers in traverso_02_0708, i.e. costs for all years are referenced to constant 2010 10GE LR cost
  3. Decreasing 10GE LR XFP cost, as implicitly used in some reflector emails, i.e. costs for a given year are referenced to 10GE LR cost in that same year.


Other cost references may have been used as well.


When you state that CWDM cost floor is 4x and Serial cost floor is 2x, are you are referencing both to decreasing 10GE LR XFP cost, or are you referencing one to decreasing cost and the other to constant cost?


Going forward, I would recommend that anytime a cost multiplier is used that it is accompanied by what it is being referenced to.


Thank you




From: Atsushi Takai [mailto:atsushi.takai@xxxxxxxxxx]
Sent: Saturday, August 16, 2008 8:56 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF




I also back from my vacation.

However I will visit my hometown for my mother's "Hatsubon" (Japanese important ceremony).

Thus I can not discuss promptly but I would like to try to discuss.



> I wouldn't want to predict much difference in a future poll/vote from the 68% vs 32% we had in Denver.


It may not be true because I received e-mails from some people who became serial supporter.

(I do not avoid the possibility that other some people changed change to CWDM.)



I believe we have to define standard using "right" technology as Gary pointed.


I believe CWDM is not "right" technology.


  I believe that a standard must give some profit or merit.

  The largest profit in this standard is to give wider bandwidth with lower cost and lower power consumption, and maybe smaller size.

  I was informed, we are requested 6x10G cost at least as a target for 100GbE (10x10G bandwidth).


  Thus the "right" standard must be achievable to lower cost/bit and lower power consumption/bit target.


  During the discussions, it is not clear how to reduce cost less than 4x in case of CWDM.

  Or it seems it is almost impossible to reduce cost from 4x significantly.


  Thus I have a big question mark for CWDM that may not improve at least cost/bit.

  I believe CWDM is not "right" technology.


I believe serial is  "right" technology.


  How long have we been using 100M, 1G and 10G standard?

  We must not decide only for the "best" solution in 2010 or so.


  The "right" standard must remain long term, say longer than 10 years.


  Many discussions were how to reduce cost and when crossover would happen in case of serial.


  Ali's mail reminded me the Newport CMOS.

  I discussed with Newport in Q1, 2000 in detail

  I know the same level of 40G CMOS IC today.

  And I know there needed some step from prototyping IC to market available IC.


  Also I know many efforts for 40G DFB.

  We used GPPO for 10G in early stage but we were successful to remove it.


  We know how to reduce cost for 40G serial in near future.

  Our target is 2-2.5 times of 10G.


I think MSA is enough for short term solution if necessary.


  There is X40 MSA ( ) that is very similar to CWDM 40G.

  We may establish new MSA based  X40 MSA to fit for 40GbE.


I think we will take off CWDM from the table until CWDM will be proven the significant cost/bit improvement.

We should focus if serial is right technology for standard, while I believe no doubt.



Atsushi Takai
Marketing Division, Opnext Japan, Inc



----- Original Message -----

Sent: Friday, August 15, 2008 10:59 PM

Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF




I'm just back from a week's vacation and just finished reading all the reflector traffic on this topic.  I was just coming to the same conclusion as you when I finally got to your email.


Based on my assessment, we have no new information available to us.  It is already all out there and available to the group.  The difference is that people are taking that information and interpreting it in different ways to reach their position dependent on their priorities and points of view.  I wouldn't want to predict much difference in a future poll/vote from the 68% vs 32% we had in Denver.  We therefore have entrenched positions.


Seems the only two options are to slow the whole standard's progress down while we debate this topic (note that we have no new information though so not sure the value in that), or else remove the objective per Alessandro's note.


My observation is that this is arguably gone past the technical considerations.  That is over, the majority of the data is available.  This is now essentially a non-technical issue on how we get closure on the issue.  Can the ~ 2:1 majority position get past the 75% hurdle or does the group need to make the necessary procedural decisions to allow the standard to maintain it's agreed target schedule?


I'd prefer to debate this aspect more than further clarifications on cost analyses...





From: Thananya Baldwin [mailto:thananya@xxxxxxxxxxx]
Sent: Friday, August 15, 2008 3:48 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF

All -
Seeing the traffic on this email thread, is it time to consider Alessandro's possible scenario c) [excerpt from his email dated 7/31/8] 

… My concern now shifts to how to resolve the impasse without impacting the standard. … c) We give up the objective (I can't believe I am writing this:-) because we can't get consensus. At that point I think the market will decide.

Would be an interesting data point to see where the TF stands on this option.

Thananya Baldwin
Director of Strategic Programs