RE: [10GBASE-T] September interim meeting
Bruce,
I think I
agree that data centers are enough to fulfill broad market potential for
10GBASE-T. For some years to come, I think that (plus perhaps some
switch-to-switch connection if the media and distance supports it) would be the
main volume.
On power, I don't
mean that someone needs to show that they can produce today a low power
10GBASE-T transceiver. While the first 1000BASE-T transceivers used an
uncomfortable amount of power, I don't think they used so much that I couldn't
put them on a card.
I'm not expecting
exact numbers. What I would like to see for PAR approval is some estimates from
potential implementers to show that, given expected technology
improvements over the next couple of years, it will be possible to produce
transceivers (in about the time frame that we expect to be finishing the
standard) that can be used on a card - though perhaps at levels higher than
those we would all like to see long run.
There are times when
we goof and standardize something that is so far from what the market needs that
it doesn't have enough volume to get produced and improved. There are other
times where the initial parts aren't ideal but they are good enough to start
building a market and invest in improving it. The first 1000BASE-T PHYs were at
least good enough to be deployed. I would like a reasonable comfort level that
the 10GBASE-T PHYs will be over that hump.
Regards,
Pat
Pat
Thanks for providing detail on data
centers. I would argue that in terms of broad market potential, 10GBASE-T
would pass muster even if the only market application was data
centers.
On the power issue, the first 1000BASE-T implementations did
not appear until well after the standard was done, some 5 years after the High
Speed Study Group got its PAR, and consumed an obscene about of power. We
might have never achieved the low power 1000BASE-T PHYs we have today if
we had tried to agree on exact numbers in 1996.
Bruce
At 11:00
AM 7/31/2003 -0600, pat_thaler@agilent.com wrote:
Nariman,
CX4 is useful
especially when we have in rack connections to make or ones going to the
next rack. However, the distance is too short for many other data center
connects. Also, the cable for the long distance is relatively bulky which
may be a problem for some uses. We will be glad to get it, but it only
solves a corner of the problem space.
Something for the longer distances in data centers that is lower cost
than fiber would be useful. For that environment, it doesn't necessarily
have to rely on already installed wiring. Running on existing wiring is
nice, but not essential.
My view
of the important items for the data center
environment:
It must perform
solidly on the media we choose for it - data integrity factors such as BER
must be met.
It must be able to live on
"standard" server bus adapter formats with a TOE: e.g. PCI Express and
Infiniband
which means
power is a concern
It must be transparent
to existing MACs - that is, the MAC must see the same behavior it sees with
10 Gig fiber.
100 m would be desireable
(partly to enable future horizontal usage) but the data center could live
with shaving something off that. (100 m is nice from a standards development
standpoint as it saves us from arguing about what lower number is
enough.)
The media it runs over should not
be so stiff or bulky that it is a problem to accomodate with normal rack and
data center cable management.
Of couse it
must also meet EMI requirements
Regards,
Pat
- -----Original Message-----
- From: Nariman Yousefi [mailto:yousefi@broadcom.com]
- Sent: Wednesday, July 30, 2003 8:10 PM
- To: pat_thaler@agilent.com; btolley@cisco.com;
bradley.booth@intel.com; stds-802-3-10gbt@ieee.org
- Subject: RE: [10GBASE-T] September interim meeting
- Pat,
- I agree that the issues you raised must be addressed by November. One
of the biggest challenges for this group is to establish reality on
technical feasibility on Cat7, Cat6 and Cat5e channels. Different
vendors have different conclusion on Technical feasibility. That is due to
assumptions on alien cross talk mitigation techniques, impact on
implementation impairments on SNR, channel model, coding gain, and
analysis on chip complexity in a given process. Assumptions must be stated
clearly by vendors that present technical feasibility. In this case,
technical feasibility drives the broad market potential. Technical
feasibility must be addressed at least based on the following
criteria:
- 1. Achievable distance on Class D channel with and without
installation mitigation techniques.
- 2. Achievable distance on Class E channel with and without
installation mitigation techniques.
- 3. Transceiver complexity in terms of estimated power dissipation and
realistic targets for building blocks like ADC, PLL and etc 2-3 years from
now.
- We reached a conclusion that cat7 cable or class F channel has high
enough capacity for 10Gbps operation. But, can a transceiver be
built with reasonable power dissipation and cost say in 90nm process or
finer geometries to achieve broad market potential?
- We need to keep in mind that customers have fiber and CX4 as
alternatives.
- Nariman
- At 01:08 PM 7/30/2003 -0600, pat_thaler@agilent.com wrote:
- Bruce,
-
- Generally, when the group can agree on clear objectives, then they
can finish the rest of the work. Fuzzy objectives often indicate a lack
of real concensus.
-
- In November, I will also be expecting arguments that support the 5
criteria based on the objectives -
- especially:
- Broad market potential - evidence that there will be a broad market
the minimum requirements of the objectives are met.
-
- Technical feasibility - is it feasible to meet those minimum
requirements
-
- Economic feasibility - when you have met the minimum requirements
will cost be suitable to make it a viable product in the markets?
-
- In the discussions at the plenary, a power consumption issue was
raised by some of the speakers.
- If the broad market potential is based in part on use in devices
such as end nodes (including servers in data centers), then an objective
for power consumption such that this can reside in server card formats
would be important. Can it fit within the power constraints of a PCI
Express board and an Infiniband board (remembering that one has to allow
some power for the MAC and probably TOE/RDMAP engine)?
-
- Looking at the objectifves in agenda_1_07_03, I don't see any that
address power consumption or the abilitiy to live on server card
formats. In a quick search, I also didn't find any material on power
consumption in the presentations that have been made to the study group.
I hope that in September the group will address the issue of
power.
-
- Regards,
- Pat
- -----Original Message-----
- From: Bruce Tolley [mailto:btolley@cisco.com]
- Sent: Monday, July 28, 2003 1:22 PM
- To: Booth, Bradley; stds-802-3-10gbt@ieee.org
- Subject: Re: [10GBASE-T] September interim meeting
- Brad:
- Thanks for the follow up.
- I am confident that if we can agree on crisp, clear objectives for
10 Gbps reach and media supported in September that we can get our PAR
approved and move into Task Force mode, which is where the real work
begins.
- Bruce
- At 06:35 PM 7/24/2003 -0700, Booth, Bradley wrote:
- Study Group Members,
- Just to let others that were not at the meeting know the outcome
of the 802.3 Working Group meeting, the Study Group will have to
complete its PAR, 5 Criteria and Objectives in November. This
gives the Study Group the task of completing the PAR, 5 Criteria and
Objectives in 4 months. This will make our September Interim
meeting extremely important. We will need to complete the effort
as much as possible to pre-submit to the 802.3 Working Group prior to
the November Plenary. November will permit us the ability to
modify the PAR, 5 Criteria and Objectives prior to asking 802.3 to put
the PAR on the NesCom agenda. The September Interim meeting will
focus on the completion of our PAR, 5 Criteria and Objectives.
- Thanks,
- Brad
- Chair, 10GBASE-T Study Group
- Bruce Tolley
- Senior Manager, Emerging Technologies
- Gigabit Systems Business Unit
- Cisco Systems
- 170 West Tasman Drive
- MS SJ B2
- San Jose, CA 95134-1706
- internet: btolley@cisco.com
- ip phone: 408-526-4534
- "Don't put your hiking boots in the oven unless you plan on eating
them."
- Colin Fletcher, The Complete Walker
Nariman Yousefi
Vice
President Networking Engineering
PH (949) 585 5450
FAX (949)
453 1848
e-mail : Yousefi@Broadcom.com
Bruce Tolley
Senior Manager, Emerging Technologies
Gigabit Systems Business Unit
Cisco Systems
170 West Tasman Drive
MS SJ B2
San Jose, CA 95134-1706
internet: btolley@cisco.com
ip phone: 408-526-4534
"Don't put your hiking boots in the oven unless you plan on eating
them."
Colin Fletcher, The Complete Walker