Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

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



Title: RE: [802.3BA] Discussion on 40G for => 10 km SMF
Jeff
I would think that any pluggable module form factor for 40G, would support all the PMDs, PHYs and port types that result from the standards process.  Looking backwards, although XENPAK, X2, and XFP all seemed like the right solution at the time, MHO we would have better served the industry and our customers with fewer MSAs and form factors.
 
Bruce


From: Jeff Maki [mailto:jmaki@xxxxxxxxxxx]
Sent: Tuesday, August 19, 2008 10:02 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF

Atsushi,

 

X40 was a difficult situation because there was no Ethernet standard for it.  Without an Ethernet standard, it made more sense for the industry to focus on fixing the “beast” known as the OC768 VSR optic, which is too big in size, needs too much power, and has too short of a reach.  Now that we may have a standard for 40G Ethernet and have done the thorough analysis on technologies, it is best we focus on 4x10G CWDM.  The open market will arrive at a form factor is that is small in size, low in power, and low in cost using a 4x10G CWDM standard that far exceeds the original technical vision that was X40.

 

Jeffery

 

————————————————

Jeffery J. Maki, Ph.D.

Principal Optical Engineer

Juniper Networks, Inc.

1194 North Mathilda Avenue

Sunnyvale, CA  94089-1206

Desk +1-408-936-8575

Lab +1-408-936-1169

(Please leave messages by email, not voicemail.)

FAX +1-408-936-3025

www.juniper.net

jmaki@xxxxxxxxxxx

————————————————

 


From: Atsushi Takai [mailto:atsushi.takai@xxxxxxxxxx]
Sent: Monday, August 18, 2008 10:32 PM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF

 

Scott

 

I wanted to say that we could conform 40G CWDM MSA based on X40.

(Sorry for my poor explanation)

 

This X40 MSA situation gave us a hint.

 

When we were considering to join X40, we visited our customers to investigate the CWDM 40G market.

Some said "yes", but most of comments were "to focus on cost reduction of serial".

Main reason for serial was because people thought "when one device is operating 40G, why we have to consider 4-device scheme"

And market was expecting volume ramp-up.

 

The volume ramp-up, actually, did not happen due to NGN implementation delay.

But NGN implementation has started and we can expect volume ramp-up.

And we can expect 40GbE market.

Why should we go back to X40?

 

=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=
Atsushi Takai
Marketing Division, Opnext Japan, Inc

 

=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=

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

From: Scott Kipp

Sent: Tuesday, August 19, 2008 4:17 AM

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

 

Atsushi,

 

I heard that the X40 MSA is not meeting anymore and there is no standard. So the only MSA-based 40GE solution is based on the QSFP. 

 

FYI,

Scott

 


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

Mark

 

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 ( http://www.x40msa.org/ ) 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

 

Thananya,

 

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...

 

Mark

 

 


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
Ixia
thananya@xxxxxxxxxxx

-----Original Message-----
From: Chris Cole [mailto:chris.cole@xxxxxxxxxxx]
Sent: Thursday, August 14, 2008 6:16 PM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF

Mori-san,

Let me address the size questions first.

Double XENPAK size is one alternative for a quick development program for 40GE-CWDM PMD using existing components, although other alternatives are possible.

Let's assume that 2x XENPAK size is about 120mm x 72mm. This size needs to accommodate the functionality of 4 XFPs and a Mux/DeMux.

XFP size is 70mm x 18mm, so four XFPs use 2/3 of the available area.
This leaves 50mm x 72mm for the Mux/DeMux. One example of a TFF Mux/DeMux was presented in paatzsh_01_0708 with size given on page 3 as 13mm x 13mm, which leaves plenty of room for fiber routing, etc.

So your concern about having to push components into the module was unfounded.

By comparison, 40G Serial GPPO based telecom modules are now moving to 4.5" x 3.5" size (about 114mm x 90mm,) i.e. very comparable in size to the above.

With respect to cost, I do not understand your specific question about "cost down technology." What you kindly clarify what you would like me to comment on?

However, more generally I am confused as to what you are trying to accomplish with your 40GE-CWDM cost questions. There is agreement, as confirmed by your emails that the cost using existing technology is between 4x and 8x 10GE LR. Further, the initial cost in 2010 is projected as about 6x 2010 10GE LR, as in traverso_02_0708 and in several emails from Serial proponents, for example in Takai-san's

7/31/08 email. With incremental cost reduction investment this cost may asymptotically approach 4x of 10GE LR cost decreasing over time (NOT 4x of 10GE LR in a specific year like 2010.)

So what exactly is the motivation for debating a point that has agreement?

Chris

-----Original Message-----
From: Kazuyuki Mori [mailto:mori.kazuyuki-1@xxxxxxxxxxxxxx]
Sent: Thursday, August 14, 2008 8:25 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF

Chris-san

Thank you for your reply, but I found no answers for my questions about 4x10G CWDM module in your comment.
  - Cost down technology
  - Module size (double XENPAK is correct?)

And I'd like to ask below question;
  - How to push 4-TOSAs, 4-ROSAs and 2-TFFs into the module?

Thanks,
Kazuyuki Mori

 

----- Original Message -----
From: "Chris Cole" <chris.cole@xxxxxxxxxxx>
To: <STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx>
Sent: Thursday, August 14, 2008 9:02 AM
Subject: Re: [802.3BA] Discussion on 40G for ="" 10 km SMF

 

Mori-san,

Thank you for clarifying that direct connection means the use of a GPPO
adaptor instead of GPPO cable between the SerDes IC PCB and the optics.

With respect to your specific comments and questions:

1) Cost

You are correct that 802.3ba TF consensus is that 40GE-CWDM cost will be
between 4x and 8x of 10GE-LR.

HOWEVER this is relative to 10GE-LR cost over time. So a constant cost
multiplier ratio like 4x, means that the absolute cost is decreasing by
following the decrease in the cost of 10GE-LR.

Your statement that no CWDM solution will realize less then 4x cost
reduction is misleading, as already pointed out by Steve Trowbridge in
his 8/4/08 reflector email.

You are comparing a falling cost ratio of 40GE-Serial against a constant
cost reference (10GE LR in 2010,) versus a constant cost ratio of
40GE-CWDM (4x) against a falling cost reference (10GE-LR over time.)
This is not apples-to-apples.

So let's do a fair apples-to-apples comparison. On page 15 of
traverso_02_0708, 40GE-Serial with GPPO IF cost (your reflector email
proposal) in 2010 is 5.9x 2010 10GE LR cost, and in 2012 is 3.7x 2010
10GE LR cost. This represents a huge 8x cost reduction from the cost of
40GE-Serial in 2008, and then very steep cost reduction from 2010 to
2012 (1.6x.)

On the same page, 40GE-CWDM cost in 2010 is 5.9x 2010 10GE LR cost, and
in 2012 is 4.9x 2010 10GE LR cost. Since just the cost of 10GE LR will
drop from 1x in 2010 to 0.73x in 2012, this means you are claiming that
in 2012 40GE-CWDM cost is 6.7x 2012 10GE LR cost, i.e. the cost
multiplier is increasing! This will NOT be the case, and would only
happen if there was NO cost reduction investment in 40GE-CWDM.

A much more accurate cost reduction prediction is that if 40GE-CWDM cost
in 2010 is 5.9x 2010 10GE LR cost, then in 2012 it is 4.3x 2010 10GE LR
cost, i.e. following 10GE LR cost decrease.

If the same type of aggressiveness is used to predict CWDM cost as is
being used for Serial cost predictions, then 40GE-CWDM cost in 2010 is
5x 2010 10GE LR cost, and in 2012 is 3.7x 2010 10GE LR cost (less then
4x!)

40GE-Serial has no cost advantage over 40GE-CWDM in the foreseeable
future. Contrary to many statements, 40GE-CWDM cost will fall below 4x
10GE LR cost if the cost reference is 10GE LR in a given year, like 2010
which is what is used for 40GE-Serial cost predictions.

2) Size, form factor

You are making an unfair comparison of what is possible for 40GE-Serial
advanced technology with a huge investment, to what is possible with
40GE-CWDM off the shelf technology with modest investment.

To package today's 40GE-Serial technology (GPPO IF ICs and Optics) in a
pluggable form factor, something like double XENPAK is required. A
XENPAK or X2 size is not feasible.

As I commented in my 7/31/08 email to Takai-san, if we are to make a
fair comparison of advanced technology with huge investment, CWDM has a
size advantage over Serial. CWDM CDRs can be separated from the optics,
and an un-retimed form factor like QSFP becomes possible with optics
integration. For Serial, the SerDes always have to be packaged with the
optics leading to a size disadvantage for both space and thermal
reasons.

3) CWDM optics connection

The proposal for quick time to market 40GE-CWDM product is to use
existing discrete 10G OSAs (with DFBs on the CWDM grid) connected with
separate fibers to discrete TFF, similar to what was presented in
paatzch_01_0708 but for CWDM.

Thank you

Chris

-----Original Message-----
From: Kazuyuki Mori [mailto:mori.kazuyuki-1@xxxxxxxxxxxxxx]
Sent: Wednesday, August 13, 2008 9:50 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Fwd: Re: [802.3BA] Discussion on 40G for ="" 10 km
SMF

Chris-san,

Actually, a female-female adaptor is used for GPPO connection. I know
the
cost of every such GPPO component is relatively high when compared to
10GE
LR XFP component cost.
This kind of RF interconnection technologies enables us to reduce size
(XENPAK or X2) and cost of 40GE Serial modules.

Anyway, I don't know the details of 4x10G CWDM module.
1)Cost
    TF consensus are 4x-8x of 10GE LR and no solution to realize under
4x.
2)Size, form factor
    What kind of form factor do you use, double size of XENPAK?
3)Connection between optics
    Do you use discrete optics? Do you use fiber to connect between
optics?

Thanks,
Kazuyuki Mori

----- Original Message -----
From: "Chris Cole" <chris.cole@xxxxxxxxxxx>
To: <STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx>
Sent: Wednesday, August 13, 2008 4:01 AM
Subject: Re: [802.3BA] Fwd: Re: [802.3BA] Discussion on 40G for ="" 10 km
SMF

 

Mori-san,

The only commercially available PCB edge mount GPPO connectors I know
have male polarity, which is the same as XLMD GPPO connectors.

Are you developing commercial female polarity PCB GPPO connectors that
could be directly connected to the XLMD GPPO connectors?

Or by direct connection do you mean that instead of flexible
female-female polarity GPPO cable you use rigid female-female polarity
GPPO bullet?

As you know, the cost of every such GPPO component is significant when
compared to 10GE LR XFP component costs.

Thank you

Chris

-----Original Message-----
From: Kazuyuki Mori [mailto:mori.kazuyuki-1@xxxxxxxxxxxxxx]
Sent: Tuesday, August 12, 2008 12:25 AM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Fwd: Re: [802.3BA] Discussion on 40G for ="" 10 km
SMF

Chris-san,

We connect the PCB edge mount GPPO connectors and GPPO connectors on the

XLMD optics directly. Therefore we can eliminate the GPPO cable and
reduce
module size.

Thanks,
Kazuyuki Mori

 

----- Original Message -----
From: "Chris Cole" <chris.cole@xxxxxxxxxxx>
To: <STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx>
Sent: Tuesday, August 12, 2008 3:50 PM
Subject: Re: [802.3BA] Fwd: Re: [802.3BA] Discussion on 40G for ="" 10 km
SMF

 

Hello Mori-san,

Thank you for continuing to fill in the details of the 40GE-Serial
baseline
proposal.

You correctly point out that edge mount type GPPO connectors are
commercially available. Various types of such edge connectors are used
on
all 40G GPPO IC and Optics packages, and ship in 10Ks volume into
telecom
applications.

Is is reasonable to assume that the interconnect between the PCB edge
mount
GPPO connectors and GPPO conectors on the XLMD optics are GPPO cables,
similar to cables used in 40G modules today, for example as shown in the

left hand photograph on page 8 of traverso_02_0708?

Chris

________________________________

From: Kazuyuki Mori [mailto:mori.kazuyuki-1@xxxxxxxxxxxxxx]
Sent: Mon 8/11/2008 10:37 PM
To: STDS-802-3-HSSG@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3BA] Fwd: Re: [802.3BA] Discussion on 40G for ="" 10 km
SMF

 

Hello Chris-san,

Sorry for our insufficient information for RF interconnection. In case
of
XLMD, we use an edge mount type GPPO connector at the end of PCB, so we
can
apply the SMT type package for SerDes as shown on the right side of page
6
of traverso_02_0708. We already confirmed the characteristics of this RF
interconnection; the result shows 50GHz BW. As you know well, the edge
mount
type GPPO connector is already commercially available.

Thanks,
Kazuyuki Mori