Re: [802.3BA] Discussion on 40G for => 10 km SMF
802.3ba Task Force members,
Allessandro's & Steve Trowbridge's emails today summarize very well the
views and considerations which I have also gone through the past 75 days or
so since the May Munich meeting. I did not enter the start of this process
with a strong disposition either way, other than having a fairly detailed
personal history with serial 40G Transponders from my years at Big Bear.
After receiving the data and material from the various CWDM & serial
proponents after the May meeting and weighing this not only against the
needs of my current customers (who tend to be more transport/OTN-oriented
service providers / carriers than data center users), as well as positioning
it against the stated BMP needs that drove the creation of this new PHY, it
ended up being a very clear decision for the best path forward. My support
of http://www.ieee802.org/3/ba/public/jul08/gavrilovic_01_0708.pdf for the
4xCWDM PHY as presented in the July meeting was the result of this
deliberate & careful consideration (although anyone that knows me and
remembers the January & March '08 meetings, understands that I nearly wanted
to saddle this PHY with a serial solution, as I have never been a big
advocate of its inclusion in the standard). Clearer heads prevailed...
In closing, several service provider and carrier customers have voiced their
concerns to me privately the past week regarding the potential of this issue
to delay the progress of the overall 803.3ba efforts, and I ask that they
not only raise this concern to the list, but also put forward their views on
the 40G SMF PHY technology selection. I am confident that this input will
be pivotal to resolving the selection and allowing the task force to move
forward.
Regards,
John
-----Original Message-----
From: Alessandro Barbieri (abarbier) [mailto:abarbier@xxxxxxxxx]
Sent: Thursday, July 31, 2008 2:17 PM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Discussion on 40G for => 10 km SMF
Colleagues,
I'd like to follow up my previous post with the checklist that I used to
reach my decision to support CWDM.
I hope the abstains can use a similar decision tree to come up with
their own conclusion and help clear this last roadblock on the way to
D1.0.
1) Technology risk assessment
On one end we have CWDM which everyone seems to know how to build, it
has a clear technology path and uses known components for the most part
inherited by the 10G world with the associated benefit of riding the 10G
cost curve (to a large extent).
On the other end we have a technology designed for OC768, which we are
trying to morph into something a tier-2 data center/enterprise user
might be willing to buy (that is the largest segment of end users we
accepted to serve with this objective). The maquillage will have to
touch the laser wavelengths, the SERDES, a new packaging for
tosa/rosa/ldd and a bunch of other things.
I keep hearing that if serial does not become a standard these great
breakthroughs probably won't happen. This is like asking the standard to
create a problem to solve, rather than to find a solution for a real
problem.
If there is such confidence in these technology why don't people go off
and invest regardless of the standard? What is stopping them? This
insecurity and need of external justifications (IEEE) makes me wonder...
CWDM wins it for me.
2) Cost cross-over
On one end we have CWDM where I see neither uncertainty nor
disagreement. I know what I get and btw I think this is exactly what we
need to keep this market going for the next few years.
On serial there are two views and *no consensus*:
a) The serial supporters in the past few months went through an
escalation of optimism and finally reached CWDM parity in 2010...from
this side I've now come to expect further analysis in September
concluding 2009 is the crossover year.
a) I've then assisted to a well documented analysis based on historical
(=real) data in cole_04_0708, which concludes crossover 2013 "with more
likely cross-over after 2016".
CWDM wins it for me.
3) Overall health of the industry
Is the industry better off with something that few can master (the
serial breakthroughs) or by something that many can confidently build
off of existing technologies?
CWDM wins it for me.
4) Future of 40G beyond 802.3ba
Is 40G serial a good idea in the longer run?
Can we use 40G serial technologies as building blocks for other 40G
/100G applications or is it a dead end?
Is serial really the best solution to converge 40G on one form factor
(say QSFP)?
Or will it ever support MMF duplex applications?
Who really knows...so rather than picking serial for 2015 with all the
risks highlighted above, right now CWDM wins it for me.
Final score CWDM-Serial 4:0
Alessandro
> -----Original Message-----
> From: Alessandro Barbieri (abarbier)
> Sent: Thursday, July 31, 2008 11:18 AM
> To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
> Subject: Re: [802.3BA] Discussion on 40G for => 10 km SMF
>
> Dear Atsushi and colleagues,
> we've debated at length the issues of
> cost/crossovers/enabling technologies/etc and yet it seems
> difficult to make progress towards 75% consensus.
>
> A group of system vendors or "customers" of 40G components,
> got together and with an open-minded unbiased attitude looked
> at all the arguments mentioned above; we carefully reviewed
> the arguments on both sides and came to the conclusion that
> CWDM is preferred to jumpstart the 40G SMF market.
> After all as a product manager whose job is to steer product
> decisions based on listening to what my customers want, I was
> hoping this was a constructive approach to help move the work
> of the TF forward.
>
> My concern now shifts to how to resolve the impasse without
> impacting the standard.
> I see three possible scenarios:
> a) The serial camp who represented ~30% of the consensus
> comes up with a plan to get the remaining 45%.
> b) The CWDM camp supported by ~70% of the TF comes up with
> few extra votes.
> 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.
>
> In Motion #8 (see below) 31 TF members abstained, this is a
> good time to
> *try* to make a decision one way or another. I hope the
> undecided will use the reflector to solicit more information
> and help the TF reach a decision in September.
>
> We need to move the standard forward or else we end up
> impacting the whole industry effort on HSE.
>
> Alessandro
>
>
> [...Move to adopt 4x10G CWDM as per "cole_03_0708.pdf" as the
> baseline proposal for the 40GE 10km SMF PMD objective.
> Moved by: Chris Cole
> Second by: Pete Anslow
> Technical (>75%)
> Results:
> Task Force
> Yes: 81
> No: 38
> Abstain: 3
> 802.3 voters:
> Yes: 52
> No: 22
> Abstain: 8...]
>
>
>
>
>
>
>
> ________________________________
>
> From: Atsushi Takai [mailto:atsushi.takai@xxxxxxxxxx]
> Sent: Thursday, July 31, 2008 12:18 AM
> To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
> Subject: Re: [802.3BA] Discussion on 40G for => 10 km SMF
>
>
> John
>
> Thanks.
> I may understand.
> If you will find any violation below, please let me know.
>
>
> TF members
>
> I am supporting 40G serial.
> My view on 40G Serial and CWDM is as below.
>
> (1) COST
>
> We can achieve less than 4x10G cost using 40G serial
> while we need some breakthrough technology using 40G CWDM
>
> I agree 40G CWDM will be 4-8 times of 10G as written in
> "cole_04_0708" page 8.
> And most likely 6 times.
> Using current technology, it is difficult to achieve
> less than 4 because we have to pay for wavelength control.
> In case of 40G serial, module structure is the same as X2.
> I believe we can achieve less than 4 times cost for
> each part in the 40G module comparing 10G serial.
> We are waiting 3rd generation SERDES and 2nd generation
> of driver and TIA IC to achieve low cost 40GbE serial.
> I am sure that industry is working on these devices.
>
> (2) Time
>
> There exists plural 40G serial module vendors today
> using 1550-nm EA-DFB.
> 1310-nm EA-DFB is easier because we can neglect
> dispersion problem.
> Thus 40GbE serial is possible.
> And cost reduction plan is visible.
> I also sure 40G CWDM will be available if market will
> accept larger than 4 times cost.
> Cost reduction plan will follow the same as 10G and
> plan for less than 4 times is invisible today.
>
> (3) Power consumption
>
> We need also breakthrough to achieve less than 4 time
> power consumption using CWDM.
> Power consumption reduction plan is invisible
> We are sure we can achieve less than 4 time power
> consumption using serial in future.
>
> (4) Size
>
> I am not sure it is too early to talk 40G electrical interface.
> But 40GbE serial has possibility for XFP or SFP+ size.
> I did not hear LX4 XFPor SFP+ due to pin constraint and
> power consumption.
>
> (5) Risk for wavelength failure
>
> WDM technology has always the risk for wavelength
> failure, while serial does not have.
> We may resolve some way for 40G CWDM because of high
> reliability of long wavelength optical devices.
>
> (6) Another aspect
>
> We made speed breakthrough every 4 or 5 years
> in the past.
> AND
> We started to deliver 10G modules in 1997.
> The 300-pin MSA started in 2000.
> 10GbE was issued in 2002.
> 40G is the next milestone for technology evolution and
> now is a little bit behind the past trend.
> (We had unhappy period that every progress seemed to stop.)
> Today 40G is the technology to challenge and overcome
> for both optical and electrical technology.
> I think IEEE should not avoid such technology evolution.
>
> I believe IEEE should take 40GbE serial.
>
> =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=
> Atsushi Takai
> Marketing Division, Opnext Japan, Inc
>
> =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=
>
> ----- Original Message -----
> From: John DAmbrosia <mailto:jdambrosia@xxxxxxxxxxxxxxx>
>
> To: Atsushi Takai
> <mailto:atsushi.takai@xxxxxxxxxx> ;
> STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
> Sent: Wednesday, July 30, 2008 8:30 PM
> Subject: RE: [802.3BA] Discussion on 40G for =>
> 10 km SMF
>
>
> Atsushi,
>
> First, let me say that the email below is
> intended to make sure that this group does not stray in a
> direction that would ultimately lead to the violation of
> IEEE-SA Antitrust and Competition Policy. As chair, I am
> remaining neutral on the TF's technical decisions.
>
>
>
> Regardless of the decision that this body
> makes, the market may demand that both solutions are
> developed anyway.
>
>
>
> Please note in the following document from the
> IEEE, "Promoting Competition and Innovation:
>
> What You Need to Know about the IEEE Standards
> Association's Antitrust and Competition Policy," which may be found at
> http://standards.ieee.org/resources/antitrust-guidelines.pdf. Please
> note the following statement:
>
>
>
> "For example, selecting one technology for
> inclusion in a standard is lawful, but an agreement to
> prohibit standards
>
> participants (or implementers) from
> implementing a competing standard or rival technology would
> be unlawful - although as a practical matter, a successful
> standard may lawfully achieve this result through the
> workings of the market."
>
>
>
> As I have phrased it to the Task Force, the
> Task Force makes decisions about what it is going to do, it
> does not make decisions about what it is not going to do.
>
>
>
> Regardless of the decision that this Task Force
> makes, it is very easy to envision both implementations
> getting developed in the industry. Given the need stated by
> CWDM supporters for a near term solution, it is easy to
> envision an industry effort happening if the TF goes serial.
> It is just as easy to envision a new CFI happening for a
> serial solution if the TF chooses to go CWDM.
>
>
>
> Also, as a point of clarification, as I am
> currently looking at the presentation for another discussion,
> you may wish to refer to Flatman_01_0108
> (http://grouper.ieee.org/groups/802/3/ba/public/jan08/flatman_
> 01_0108.pd
> f), which is a survey of data centers that Alan Flatman did
> that shows 40G being deployed in access-to-distribution links in 2010.
>
>
>
> Regards,
>
>
>
> John
>
>
>
>
>
>
>
>
>
> ________________________________
>
> From: Atsushi Takai
> [mailto:atsushi.takai@xxxxxxxxxx]
> Sent: Wednesday, July 30, 2008 2:26 AM
> To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
> Subject: Re: [802.3BA] Discussion on 40G for =>
> 10 km SMF
>
>
>
> Hi Mark
>
>
>
> I agree that DC application is cost sensitive.
>
> As many people agreed in some presentations at
> meeting, CWDM will be cheaper at near term and serial will
> became cheaper in maybe 2011 or beyond.
>
> That means transceiver supplier have to develop CWDM in
> 2009 timeframe and serial in 2010 or 11.
>
> This development will cost much. And I do not
> think CWDM cost in 2009 or 2010 will be cheaper than 4x10G.
>
> Even more DC application users can choose 8x10G
> CWDM that has more bandwidth.
>
> I do not think CWDM has superior merit for DC
> application.
>
> Also I think there was a presentation that said
> that DC will start install 40G in 2015 or beyond.
>
>
>
> =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=
> Atsushi Takai
> Marketing Division, Opnext Japan, Inc
>
>
>
> =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=
>
> ----- Original Message -----
>
> From: Mark Nowell (mnowell)
> <mailto:mnowell@xxxxxxxxx>
>
> To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
>
> Sent: Wednesday, July 30, 2008 4:08 AM
>
> Subject: Re: [802.3BA] Discussion on
> 40G for => 10 km SMF
>
>
>
> John,
>
>
>
> I agree some reflector discussion would
> be helpful on this topic.
>
>
>
> I characterize the discussion I heard
> around the choice of PMD as really boiling down to a debate
> on the primary applications and the drivers for those applications.
>
>
>
> The original justification for adding
> the 40G SMF objective was primarily based on the application
> of Data Center inter-switch links. There was also other
> applications such as for use in interconnecting to OTN
> equipment which is good for BMP. In both cases lower cost
> solutions are preferential. The debate appears to revolve
> around what other assumptions there are around market timing,
> technology risks, cost projections and operational issues etc.
>
>
>
> To me the simple view is that to
> achieve low cost, you need higher volume. Higher volume is
> achieved by the having a solution that addresses the largest
> primary application and as many others as possible. I am
> assuming that the primary application is still the DC.
>
>
>
> Since DC applications are inherently
> much more sensitive to cost, a near term low cost solution is
> needed or else the application will likely not be adopted.
> In this case, if 40G SMF PMD is uneconomical in the near term
> then the DC users will likely stay with nx10G as long as
> possible and then presumably assess the 40G/100G economics at
> some later date.
>
>
>
> The argument for adopting serial
> technology now is that the potential higher volume of the DC
> application will trigger the necessary development
> investments now and drive the cost of that technology down so
> we will ultimately get it to the low cost solutions needed.
> My concern is that the timing and cost windows needed for the
> DC application do no fit with that model and we would end up
> with little adoption in that market and end up with a lower
> volume, higher cost PMD which is what we would all like to avoid.
>
>
>
> Mark
>
>
>
>
>
>
>
> ________________________________
>
> From:
> John DAmbrosia [mailto:jdambrosia@xxxxxxxxxxxxxxx]
> Sent: Monday, July 28, 2008 6:53 PM
> To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
> Subject: [802.3BA] Discussion
> on 40G for => 10 km SMF
>
> Dear Task Force Members,
>
> Per Motion #9 from July, the
> editorial team is working on creating a "a draft based on
> adopted baseline proposals for circulation prior to the
> September 2008 interim meeting
>
> ." Unfortunately, at the July
> meeting the Task Force did not reach consensus on a baseline
> proposal to satisfy
> the 40G over => 10km SMF objective. Therefore, in September we need
> to reach closure on this issue.
>
>
>
> With that said, I would like to
> strongly recommend that the TF make use of the reflector to
> discuss the various issues of debate that have been going on,
> both during the meetings and during offline discussions.
>
>
>
> Let's use the next several
> weeks to have meaningful debate so we can reach consensus at
> the September meeting.
>
>
>
> Regards,
>
>
>
> John D'Ambrosia
>
> Chair, IEEE P802.3ba Task Force
>