RE: [10GBASE-T] Technical feasibility: power
Xiaopeng:
I
don't remember anyone demanding nor anyone promising that 1000BASE-T would be
deliverded at 1 Watt at any stage in developing the standard. I know of
multiple initial implementations of 1000BASE-T with higher power
consumption. For me personally, the comparison point isn't an arbitrary
watt number, but is relative to the power consumption of 10 GbE optics
modules.
Brad:
I
found no mention of power consumption in the 802.3z critters or objectives, nor
in the 802.3ab critters or objectives I sampled.
·
Est. Gate Count/Power Consumption:
330K/4W
FYI,
the 802.3ab objectives listed in that presentation were
·
Comply with specifications for GMII of
802.3z.
·
Provide line
transmission which supports full and half duplex
operation.
·
Provide FCC Class A/CISPR or better
operation
·
Support operation over
100 meters of Category 5 balanced
cabling
·
Achieve bit Error Rate better than to 10
-10
·
Support Auto-Negotiation (Clause
28)
·
Meet susceptibility requirements
·
Support the objectives of 802.3z of Nov. 13,
1996
--Bob
Grow
I
believe that the power number would be a big factor in the economic feasibility.
If we are talking about a 1 Watt part, then it is not a big deal, but if a
much higher number turns out, everyone might give a second thought on whether it
is even worth to implement it.
Just my thought,
Xiaopeng
|
| "Booth, Bradley"
<bradley.booth@intel.com>
07/31/2003 02:45 PM
|
To:
<xichen@marvell.com>,
<stds-802-3-10gbt@ieee.org>
cc:
Subject:
Re: [10GBASE-T] Technical feasibility:
power |
I
was trying to recall if 802.3 used and specific power numbers in the GbE and
10GbE objectives or 5 criteria. Considering I don't have web access right
now, I'm just going by memory. I believe 802.3 did not dictate power
requirements, but did use power estimations in selection of the PHY to put into
the draft. This is just a Study Group, so it may only be required that to
state that due consideration will be given to the power
requirements.
Thoughts?
Thanks,
Brad
-----------------
Sent
from my BlackBerry.
-----Original Message-----
From:
xichen@marvell.com <xichen@marvell.com>
To: stds-802-3-10gbt@ieee.org
<stds-802-3-10gbt@ieee.org>
Sent: Thu Jul 31 13:52:04 2003
Subject:
RE: [10GBASE-T] Technical feasibility: power
Burce,
That is
what I called painful lessons. The customers always want parts that have
high performance margin and low power. I believe that has become the rule
for our designers unless you really want something that can also fry eggs.
In order to give a reasonable estimation of the power comsuption, we
should defintely take into account all possible technology and design tricks
that we know and we can use in 5 years. Of course, we cannot predict any
magic stuff that can save the world will come out soon, but we can wait.
A well-estimated number will save a lot words.
Xiaopeng
Bruce Tolley <btolley@cisco.com>
07/31/2003 12:56 PM
To:
xichen@marvell.com, Bruce Tolley <btolley@cisco.com>
cc:
Subject: RE: [10GBASE-T] Technical
feasibility: power
Xiaopeng
Thanks for the
response
The first 1000BASE-T parts were much more than a few watts. Also
the power numbers on the roadmaps of the various vendors started dropping as
soon one of the competitors achieved lower power numbers. All the sudden, the
impossible became possible.
And yes we need data to be presented in
September.
Bruce
At 11:10 AM 7/31/2003 -0700, xichen@marvell.com
wrote:
Hi,
I believe that everyone of us has painfully learned a
lot from the history of 1000BASE-T. We have observed the power of a single
1000BASE-T dropped from a few watts to sub-watt level today. And we can
pretty confidently assess the impact of the technology that we are gonna use in
5 years and we definitely should take that into account NOW.
Many
circuit design experts will tell you that the power of digital circuit part can
be scaled down while the semiconductor technology got significant improvement in
the following years (how about using 65nm when 10GB-T reach the market), but the
analog circuit part won't get too much benefit from that and its performance
(for example, the ADC resolution) will be limited by some fundamental physical
rule. Due to the complexity increase of the DSP part and the analog part,
even using 65nm technology for digital circuit and using SiGe technology for
analog circuit, to reach 100m on CAT-7, the estimated power of the transceiver
(assume it is practically feasible) will be a number that can surprise you.
I believe more and more data will be given in the following meeting to
show you the reality.
Xiaopeng
Bruce Tolley
<btolley@cisco.com>
Sent by: owner-stds-802-3-10gbt@majordomo.ieee.org
07/31/2003 10:12 AM
To: pat_thaler@agilent.com, yousefi@broadcom.com,
pat_thaler@agilent.com, btolley@cisco.com, bradley.booth@intel.com,
stds-802-3-10gbt@ieee.org
cc:
Subject: RE:
[10GBASE-T] September interim meeting
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>
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> 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
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