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Re: [802.3_DIALOG] [STDS-802-3] Call for interest - 40Gb/s Ethernet Single-mode Fibre PMD

David - thanks for setting this up.

I am not seeing where this request for CFI is inappropriate.  In your comments you point to the CFI failing the Distinct Criterion.  How is that possible?  As far as I know there is no such rule for a CFI.  Clearly, if a study group is formed, that study group will then be responsible for defining a project that would meet the distinct identity criterion.

As far as fixing "perceived deficiencies" with the P802.3ba, I do not believe there are any.  A single objective to cover 40G over 10km was adopted.  Decisions were made by the Task Force that resulted in a decision to go with the current 40GBASE-LR4 solution, but the Task Force also took the following straw poll at the time the decision was made to go with the 40GBASE-LR4 proposal (at which time 97 people had voted y/n/a):

Straw Poll #5 (See Page 10):
I believe that the 40GbE serial PMD proposal is worthy of consideration in a future project.
Results:	Y: 86

I interpret this as significant interest by those present in the 802.3ba group at that meeting in a serial effort, but a desire to focus on the adopted proposal for the current defined project.

The decision of the Task Force and this subsequent straw poll was reported to the 802.3WG at my opening plenary report in Nov 2008.  Please see 

In my opinion further offline discussions, however, illustrated to me that many asking for the serial solution were really looking for a solution for the application space defined in the CFI request made by Mark Nowell: "What are the needs of the carrier space?  In my opinion this question clearly illustrates why we use study groups.

With that said if a study group is formed, it would clearly be the responsibility of the study group to respond to the 5 criteria.  And I would have to see these responses before voting yes to approve the PAR / 5 Criteria / objectives.

As far as the scope of 802.3ba covering this effort, that point could be argued.  However, I think we would both agree that .3ba is already a fairly large project, but IMHO everyone agrees that there will be future PHYs that will get added to the 40/100G family.  There is precedence, however, for adding a PHY, which could of fit into another project's scope.  Look at Gigabit Ethernet and 1000BASE-T.  

The scope of 802.3z read: 
	Define Carrier Sense Multiple Access with Collision Detection
     (CSMA/CD) Media Access Control (MAC) parameters and minimal
     augmentation of its operation, physical layer characteristics, 
     repeater functions and management parameters for transfer of 
     802.3 and Ethernet format frames at 1,000 Mb/s.  
     Provide for both full and half duplex operation at 1,000 Mb/s 
     based on approved 802.3 projects and the 802.3 standard.

This would have covered 1000BASE-T.  However, in looking at the project, the first meeting of the 1000BASE-T Task Force was Sept 97.  At the time it was one meeting cycle before the 802.3z Task Force was scheduled to request going to sponsor ballot.  So there is precedence.  Also, this effort is often cited as a Task Force spinning out a project - though it is still not clear to me per the rules, how a Task Force goes about that.  I guess, as it is often said, this is an example of 802.3 doing something when there is consensus to do it.



-----Original Message-----
From: David Law [mailto:David_Law@3COM.COM] 
Sent: Friday, October 30, 2009 8:03 AM
Subject: Re: [802.3_DIALOG] [STDS-802-3] Call for interest - 40Gb/s Ethernet Single-mode Fibre PMD

Dear Colleagues,

I received the following comment from Geoff Thompson in response to the 
40Gb/s Ethernet Single-mode Fibre PMD Call for Interest announcement. To 
keep the email burden low this IEEE 802.3 reflector is only used for 
announcements and hence is not the appropriate venue to discuss this 
issue. Since there wasn't really anywhere else that was appropriate I have 
taken the step of setting up an IEEE 802.3 general discussion reflector at 
the email address [] which I have CCed this 
message to.

The IEEE 802.3 general discussion reflector is an opt-in reflector so if 
you wish to discuss this issue please subscribe to the IEEE 802.3 general 
discussion reflector at the URL [ ] or follow the discussion 
in the reflector email archive at the URL [ ].

Best regards,

Geoff Thompson <> wrote on 08/10/2009 19:41:18:

> David-
> It seems to me that it should be considered whether or not this CFI is 
> proper.
> That is, the scope as described in the CFI announcement, "40Gb/s 
> Ethernet Single-mode Fibre PMD optimized for client applications in the 
> carrier environment. " lies fully within the scope of an existing 
> project that has yet to be put into Sponsor Ballot. That scope (I 
> believe, currently) reads: "Define 802.3 Media Access Control (MAC) 
> parameters, physical layer specifications, and management parameters for 

> the transfer of 802.3 format frames at 40 Gb/s and 100 Gb/s."
> The scope of the existing project has nothing limiting the reach of the 
> existing project nor any details limiting what PMDs might be included 
> within that project
> Therefore, by definition, the CFI fails the "Distinct Identity" 
> Thus, at this point, the proponents of this PMD should be focusing their 

> efforts on fixing their perceived deficiencies in the existing project 
> rather than starting a new one that is within the scope of a current 
> project.
> Sincerely,
> Geoff Thompson
> On 10/8/09 5:23 AM, David Law wrote:
> > TO: IEEE 802.3 Voters, Observers and Liaisons
> >
> > Dear Colleagues,
> >
> > The following request for agenda time for a 'Call for interest' has 
> > received from Mark Nowell. It will be discussed at the IEEE 802 LMSC
> > November 2009 Plenary meeting in Atlanta, GA, USA. If you have any
> > questions please get in touch with either Mark Nowell 
> > or myself directly.
> >
> > ----
> >
> > 40Gb/s Ethernet Single-mode Fibre PMD Call for Interest
> >
> > This is a Call for Interest in forming a Study Group to study the need 
> > an amendment to the IEEE 802.3 standard to specify a 40Gb/s Ethernet
> > Single-mode Fibre PMD optimized for client applications in the carrier
> > environment. Based on this study the outputs will be (i) a 
> > to the IEEE 802.3 Working Group if such a amendment is required and 
> > if so a PAR, 5 Criteria and Objectives in support of a project to 
> > the amendment.
> >
> > ----
> >
> > The 'Call for interest' occurs during the IEEE 802.3 Opening Plenary 
> > the afternoon of Monday 16th November. A 40Gb/s Ethernet Single-mode 
> > PMD Call for Interest meeting has been requested for Monday evening 
and I
> > will provide full details in my plenary announcement email in a couple 
> > weeks time. The vote to determine if a Study Group will be formed will
> > take place at the IEEE 802.3 Closing Plenary on the afternoon of 
> > 19th November. For more information about the plenary meeting please 
see [
> > ].
> >
> > Best regards,
> > David Law, Chair, IEEE 802.3 Ethernet Working Group
> > Phone: +44 131 665 7264
> > Email:
> >
> >