Re: [802.3BA] 5 Criteria mod to support 40 G on SMF
Those points are valid.
However, in a 10 km single mode link, it is the fiber
that is the most expensive piece of the link, and also
the most difficult to upgrade. The advantage of a
40 Gb/s link is that a customer can install a lower cost
link in a timely manner, and then later, when their
requirements rise to 100 Gb/s link, they can pull the
fiber out of their 40 Gb/s device and plug it into
their 100 Gb/s device. That granularity of bandwidth
is likely to increase the market for Ethernet, since
short-term Ethernet solutions would be cost effective and
would not demand OC-768 components. The port is
captured for Ethernet with 40 Gb/s and maintained for 100 Gb/s.
Customers like just-in-time bandwidth increments. Stated
another way, customers hate to pay a lot for bandwidth
they don't yet need.
Bob
-----Original Message-----
From: Dove, Dan [mailto:dan.dove@HP.COM]
Sent: Friday, February 15, 2008 9:30 AM
To: STDS-802-3-HSSG@LISTSERV.IEEE.ORG
Subject: Re: [802.3BA] 5 Criteria mod to support 40 G on SMF
Howard,
You said " Customers tend to be pretty smart people. They know what they
need, they know how to calculate cost/performance ratios, and they know
how to pick the right data rate for each of the links in their
networks." and I fully agree with you, but your point does not address
the fact that customers for 100G 10km LANs would find themselves with
two solutions now rather than one. These two solutions would be
sufficiently similar in performance, and perhaps a significant
difference in cost, that we would see that customer base split between
40G and 100G with very small incremental volume gained by the addition
of 40G.
If this is true, we have doubled the amount of work to yield a
fractional increase in market growth.
In addition, those customers who go for the 40G solution because its
available sooner or lower in cost will find themselves quickly in a
state where they need 100G, thus they have bought a technology without
the legs that are normally desired for backbone links.
Now, I don't think my points, by themselves, are sufficiently persuasive
to oppose a 40G-10km standard, but wanted to put them onto the table. We
are certainly stepping away from some of the supporting arguments made
when 40G and 100G were initially approved and should re-evaluate the
entire justification before treading too far down this path.
Dan
-----Original Message-----
From: Howard Frazier [mailto:hfrazier@BROADCOM.COM]
Sent: Thursday, February 14, 2008 5:38 PM
To: STDS-802-3-HSSG@LISTSERV.IEEE.ORG
Subject: Re: [802.3BA] 5 Criteria mod to support 40 G on SMF
The study group, the working group, and the EC all agreed that broad
market potential had been demonstrated for both 40 G and 100 G. The
broad market potential for 100 G was based, in no small part, on the
needs of very vocal and prominent individuals representing end users of
the technology. These individuals made it clear that 40 G was not
sufficient for their needs. I don't think that the inclusion of a new
objective for 40 G operation on 10 km of single mode fiber will change
their view in the slightest.
They need 100 G, and 40 G in any form simply won't satisfy their needs.
I think that this is well captured in the approved response to the broad
market potential criterion.
What has changed is that a new set of individuals are asking for 40 G on
10 km of single mode fiber because they believe it will satisfy their
needs. They aren't contradicting the people who want 100 G. They are
simply saying that their needs are different.
Customers tend to be pretty smart people. They know what they need, they
know how to calculate cost/performance ratios, and they know how to pick
the right data rate for each of the links in their networks.
We haven't had any problem with Distinct Identity over the last 16 years
that we have been cranking up the operating speed of Ethernet. Customers
know when to use 10 Mb/s, 100 Mb/s, 1000 Mb/s and 10 Gb/s. They will be
able to draw the same distinction between 40 Gb/s and 100 Gb/s,
regardless of what media types are supported.
I think it would be a terrible idea to limit the link span for 40 G
operation on single mode fiber to 2 km. Customers have been designing
around a maximum link span of 10 km (and the associated channel
insertion
loss) for at least the last decade. It would be wrong to arbitrarily
limit the span of 40 G to 2 km in an attempt to provide unnecessary
differentiation.
Howard Frazier
Broadcom Corporation
-----Original Message-----
From: Brad Booth [mailto:bbooth@AMCC.COM]
Sent: Thursday, February 14, 2008 1:00 PM
To: STDS-802-3-HSSG@LISTSERV.IEEE.ORG
Subject: Re: [802.3BA] 5 Criteria mod to support 40 G on SMF
Steve,
I agree that this does change things up. 40G was positioned as a server
interconnect, and 100G as the network interconnect. The overlap with an
existing 100G objective blurs the distinct identity making it hard to
differentiate the broad market potential for either objective.
If the 40G SMF option was being targeted at a 2 km reach, that would
make sense considering that's a typical campus area network. If someone
then wanted to use that to do 10 km, that would be their option and
considered outside the scope of the standard.
Thanks,
Brad
-----Original Message-----
From: Swanson, Steven E [mailto:SwansonSE@CORNING.COM]
Sent: Thursday, February 14, 2008 1:08 PM
To: STDS-802-3-HSSG@LISTSERV.IEEE.ORG
Subject: Re: [802.3BA] 5 Criteria mod to support 40 G on SMF
Howard etal,
I could agree that this proposal may address what needs to change in our
response to the Economic Feasibility criterion to add the 10km SMF
objective at 40G. However, I think this change goes against the basis of
the decision that we took in July 2007 for considering 40G in the first
place, i.e., segmenting the server and computing applications from the
network aggregation applications. Now the network aggregation space
includes two solutions - 40G and 100G. This seems to place a burden on
us to also re-evaluate Distinct Identity criterion and calls into
question the Broad Market Potential criterion. In reviewing some of the
presentations leading up to our decision to include 40G, I note some of
the concerns expressed then that I think are now back on the table:
* "Fragmentation of R&D efforts (lack of critical mass on either
40G or 100G initially) - two rates will ultimately force component and
equipment vendors to support BOTH."
* "Requires the industry to develop 2 x MACs, 2 x PCS chips, 2 x
PMA (serdes) chips, 2 x N PMDs"
* "Industry confusion on "application versus rate" - Distinct
Identity does not just mean "Is there anything else exactly like this?"
but also "Is there sufficient difference between this and available
alternatives to justify the effort?"
* "Interoperability concerns (some vendors elect to implement 40G
initially, whereas others implement 100G)"
* "Do we now have a triple rate required (40G LAN, 40G WAN, 100G)
since 40G SMF solutions already exist?"
I do not have any proposed changes at this point regarding the BMP or DI
criterion but wanted to express an opinion that these criterion should
be re-evaluated. If others do not share that view, then on we go.
Steve Swanson
Corning Incorporated
-----Original Message-----
From: Howard Frazier [mailto:hfrazier@BROADCOM.COM]
Sent: Thursday, February 07, 2008 6:21 PM
To: STDS-802-3-HSSG@LISTSERV.IEEE.ORG
Subject: [802.3BA] 5 Criteria mod to support 40 G on SMF
Dear members of the IEEE 802.3ba Task Force,
I have reviewed our approved set of 5 Criteria responses
http://www.ieee802.org/3/ba/PAR/HSSG_5C_0707.pdf
looking for any material that will need to be changed in the event we
adopt an objective to support 40 Gb/s operation on 10 km of single mode
fiber. In my opinion, the responses will remain valid and complete, with
one exception.
On page 6 of the above referenced file, in our response to the Economic
Feasibility criterion, we state:
Presentations indicate that for the server market and
computing applications the optimized rate to provide
the best balance of performance and cost is 40 Gb/s.
For the network aggregation market and core networking
applications, the optimized rate offering the best
balance of performance and cost is 100 Gb/s.
If we adopt a 40 Gb/s SMF objective, then this response should be
modified along the lines of:
Presentations indicate that for the server market,
computing applications and some cost-sensitive
aggregation applications, the optimized rate to provide
the best balance of performance and cost is 40 Gb/s.
For the network aggregation market and core networking
applications, the optimized rate offering the best
balance of performance and cost is 100 Gb/s.
The change being the insertion of the words "some cost-sensitive
aggregation applications" in the first sentence.
I think that our previously approved responses for Broad Market
Potential, Compatibility, Distinct Identity, and Technical Feasibility
will not require any change in the event that we adopt an objective for
40 Gb/s operation on SMF. I think that the proponents of the new
objective will be able to readily demonstrate this.
If you think I have over looked something else that might need to be
changed, please speak up, and please provide a proposed change.
Howard Frazier
Broadcom Corporation