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Re: [STDS-802-3-400G] My competing 2-km proposals

Hi Brad,

I don't think your reading of "Distinct Identity" is completely in line with precedence within the IEEE 802.3.

Take, for example, 100GBASE-LR4 and 100GBASE-ER4. They both use similar modulation approaches and wavelengths. The key difference is in the cost of components required to achieve the target reaches.

I believe the 8x50G PAM-4 proposals for 2km and 10km are a similarly distinct set of optical parameters and therefore, have different cost models to achieve the different market needs. The nice thing about this approach is it allows high leverage between what will be two relatively small markets and thus consolidation of components, design and testing elements within the manufacturing base.

I'm supportive of 4x100G for 2km, but I think the market for that solution is out in time and would be best addressed with a future project in much the same way 802.3bm came in and cost-reduced 100G solutions after 802.3ba met initial market need.

Regards,

Regards,
Dan Dove
Chief Consultant
Dove Networking Solutions
 530-906-3683 - Mobile
On 5/18/15 12:55 PM, Brad Booth wrote:
Actually, I prefer the 4x100G lambda solution for 2 kms. If one assumes the 8x50G lambda solution is the preferred proposal for the 10 km reach, I can understand the logic applied to see the 2 km reach version as a reach optimized solution for that market space.

But, if I look at the 2 km reach as it's own market where the maximum reach is 2 km on a duplex fiber, then it seems to me that this technology should more closely resemble the 500 m reach solution. If a 4x100G PSM4 solution is the preferred proposal in that space, converting that solution from PSM4 to WDM would be preferred. While there is added complexity to convert a PSM4 solution to a WDM solution, I believe that the industry would be able to capitalize on the 500 m reach volume to help drive down the cost of the 2 km WDM version.

One of the other reasons I favor having a 4x100G lambda solution for 2 km is that the task force easily means the distinct identity requirement for each reach solution. The 500 m, the 2 km and the 10 km are all unique and distinct.

Thanks,
Brad




On Mon, May 18, 2015 at 7:55 AM, Dan Dove <dan.dove@xxxxxxxxxxxxxxxxxx> wrote:
Hi Jeff,

I see things exactly the same way as you expressed it. I imagine many others also will.

Regards,
Dan Dove
Chief Consultant
Dove Networking Solutions
 530-906-3683 - Mobile
On 5/18/15 10:04 AM, Jeffery Maki wrote:

Dear P802.3bs Task Force Members,

 

I wanted to explain why I am an author of competing proposals for the 2-km reach objective, namely, 4x100G-lambda (50GBAUD) PAM-4 and 8x50G-lambda (25GBAUD) PAM-4. I began with 4x100G-lambda (50GBAUD) PAM-4 because it aligned with what I believe is best from an architectural point of view, which I had reviewed in my Norfolk presentation http://www.ieee802.org/3/bs/public/14_05/maki_3bs_01a_0514.pdf. I also considered in that presentation that technical feasibility in concert with time-to-market considerations might dictate something different than architectural optimization.

 

Here are some things I also know to be true:

1.       The market needs a durable (good longevity) interoperable standard for 10 km reach. This reach is where the market demands zero issues for interconnecting systems from different system vendors and implicitly module vendors.

2.       The market will ask for a reduced performance, 2 km reach, version and thus more importantly a reduced cost option that preserves interoperation with (1) up to 2 km.

3.       IEEE 802.3 standardization enabling higher-density solutions and/or lower cost solutions for 2-km applications will not stop (1) and (2) from continuing to be demanded and procured. Only a compelling new 10-km standard would change things for (1) and (2).

 

Thus, at this time, my priority has become 8x50G-lambda (25GBAUD) PAM-4 for the 2-km reach proposal since it aligns with the what I see as the winning 10-km reach proposal, which is 8x50G-lambda (25GBAUD) PAM-4.

 

Jeff

 

 

From: John DAmbrosia [mailto:John_DAmbrosia@xxxxxxxx]
Sent: Sunday, May 17, 2015 3:14 PM
To: STDS-802-3-400G@xxxxxxxxxxxxxxxxx
Subject: [STDS-802-3-400G] Webpage Update

 

All,

The webpage has been updated with all files I have received as of now.

Please see - http://www.ieee802.org/3/bs/public/15_05/index.shtml.

 

We will start promptly at 8:30am tomorrow (Monday) morning.

 

Regards,

 

John D’Ambrosia

Chair, IEEE P802.3bs 400GbE Task Force