Re: [HSSG] 40G MAC Rate Discussion
Title:
Shimon,
"What has been puzzling to me in
this debate ever since it started is:
how can 40Gb server connectivity in the
datacenter hurt those of you who believe that 100Gb is the right speed for
aggregation links in service provider networks? I am certainly at a point where
I understand and respect the needs of your market. All I am asking in return is
the same."
I believe I may have stated this during the meetings, but will
be happy to reiterate. First off, I should mention that aggregation is not just
for service providers, but high performance data centers are in need of 100G
aggregation *asap* as well.
If we have a 40G and 100G MACs defined, it
creates an additional set of IC/product solutions that must be
developed.
Imagine the following;
Nx10G + Mx100G + (opt) Fabric
I/O (Required for a 10G/100G Server/Uplink solution)
Nx100G + Fabric I/O
(Switch Aggregator Functionality)
So, to solve the customer demand for
higher density 10G with uplink solutions, we are likely to need two chips
and the products they spawn.
Now, If we add 40G into the
mix;
Nx10G + Mx40G + (opt) Fabric I/O (Required for a 10G/40G
Server/Uplink solution)
Nx40G + Mx100G + (opt) Fabric I/O (Required for a
40G/100G Server/Uplink solution)
Nx40G + Fabric I/O (Switch Aggregator
Functionality)
Nx100G + Fabric I/O (Switch Aggregator
Functionality)
So, we have essentially doubled the product development
requirements to meet a wider, and thus more shallow customer demand for server
interconnect and aggregation products.
Now, I am open to the concept that
a multi-speed MAC could be defined which is scaled upon the PHY lane capacity,
but this is a substantial change from our current paradigm and the development
for that approach will likely slow down the standard, add risk on the spec, and
delay the availability of 100G which I already said is needed in some of our
high-performance data centers today.
I hope this helps to open the discussion and
look forward to your questions/response.
Dan
------------ Previous
Message Below ------------
-----Original Message-----
From: Shimon
Muller [mailto:Shimon.Muller@Sun.COM]
Sent:
Monday, April 02, 2007 4:52 PM
To:
STDS-802-3-HSSG@listserv.ieee.org
Subject: Re: [HSSG] 40G MAC Rate
Discussion
Thank you for the clarification, John.
On that point,
as someone who started the 40Gb discussion back in January, I would like to make
it clear in no uncertain terms what our motivations were and still are: in no
way do we intend to impede or slow down the development and/or the adoption of
100Gb Ethernet.
We believe that doing a standard for 100Gb is important
but not enough, for the following reasons:
- The 40Gb speed will enable us to
get the most out of our servers until 100Gb becomes technically and economically
viable for server connectivity. We believe that there is a 5-year window of
opportunity for this market.
- The two speeds should be addressing two
distinct markets. This can be accomplished by defining the PMDs based on reach,
with 40Gb defined for short-reach datacenter connectivity only.
- 40Gb
connectivity at the server will require a faster aggregation speed even in the
datacenter. This will increase the market potential for 100Gb.
- Unless the
100Gb effort starts today, the technology will not be ready when we need it for
servers in 2015. I am sure your heard me say this at the last meeting, and I
meant it.
- The development of a 40Gb standard will be highly leveraged:
either from the work that was done in other standards bodies, or from the work
that needs to be done for 100Gb anyway. Therefore, 40Gb should in no way slow
down the 100Gb effort.
What has been puzzling to me in this debate ever
since it started is:
how can 40Gb server connectivity in the datacenter hurt
those of you who believe that 100Gb is the right speed for aggregation links in
service provider networks? I am certainly at a point where I understand and
respect the needs of your market. All I am asking in return is the
same.
Any comments that will help me understand and address the above
concerns would be very much
appreciated.
Regards,
Shimon.
John DAmbrosia wrote
On 03/30/07 19:48,:
> All,
>
> From discussions I have
had, I sense that there may be some confusion
> regarding the proposal for
adding a 40Gb/s MAC rate objecitve. 40 Gb/s
> has been proposed as an
additional MAC rate, not as a replacement for
> the current objective of
100 Gb/s.
>
> The presentations given have focused on the needs of
servers / end
> stations:
>
> http://grouper.ieee.org/groups/802/3/hssg/public/jan07/muller_01_0107.
>
pdf
>
> http://grouper.ieee.org/groups/802/3/hssg/public/mar07/frazier_01_0307
>
.pdf
>
> http://grouper.ieee.org/groups/802/3/hssg/public/mar07/vandoorn_01_030
>
7.pdf
>
> I encourage all to review the above presentations, and use
the
> reflector to further discuss them and / or the proposed
objective.
> This will help to assist the SG in preparing for the April
Interim, as
> well as making decisions regarding the project’s
objectives.
>
> Best Regards,
>
> John
D’Ambrosia
>
>
----------------------------------------------------------------------
>
--
>
> *From:* John DAmbrosia [mailto:jdambrosia@FORCE10NETWORKS.COM]
>
*Sent:* Monday, March 26, 2007 5:11 PM
> *To:*
STDS-802-3-HSSG@listserv.ieee.org
> *Subject:* [HSSG] 40G MAC Rate
Discussion
>
> Dear HSSG Members,
>
> As discussed in
the action plan pulled together at the end of the
> plenary week, further
discussion on adding a 40G MAC rate as an
> objective is needed. Topics of
interest include: economic feasibility,
> broad market potential, and what
pmds are desired for this rate.
>
> I would like to encourage all to
use the reflector for this subject
> matter, which could assist
individuals in their preparations for the
> interim meeting next
month.
>
> Best Regards,
>
> John
D’Ambrosia
>