RE: [10GBASE-T] September interim meeting
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
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
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Colin Fletcher, The Complete Walker
Nariman Yousefi
Vice President Networking
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