Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

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