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[10GBASE-T] Re: Objectives


A little bit of history is probably in order.  The objectives shown in July
were developed during the May interim meeting.  The multi-rate PHY proposal
did not exist until this meeting.  I have asked that both PHY proposals
should evaluate the objectives to ensure their proposals are covered and
they should try to cover what the impact will be to the 802.3 specification.


Sent from my BlackBerry.

-----Original Message-----
From: <>
To: Booth, Bradley <>;
Sent: Wed Jul 30 14:22:09 2003
Subject: Objectives


I think one area where the objectives need work is with regard to MAC
compatability. The only one I see that currently relates to it is:
Support a speed of 10.000 Gb/s at the MAC/PLS service interface

Given some of the proposals being made, I don't think this objective goes
far enough. (I note that this doesn't even say that 10 Gb/s is the only
speed that will be supported.)  In the past we have occasionally tweaked the
MAC definition to accomodate faster operation. When we are adding a new
physical layer for an existing MAC speed, we have always been careful to
design the new PHY so that it was entirely compatible with existing MACs.
For instance, when we designed 10BASE-T, we made sure that the behavior the
10BASE-T MAU exhibited when a fault occurred matched behavior that coax MAUs
produced for faults.

I propose adding an objective:
Compatible with existing MACs at XGMII and XAUI interfaces without

If there are people who don't think that should be an objective, then they
should explain what sort of modifications they expect to need and how a PHY
that is not compatible with existing MACs (including switch ports) can have
broad market potential.


-----Original Message-----
From: Booth, Bradley []
Sent: Tuesday, July 29, 2003 6:05 PM
Subject: Re: [10GBASE-T] PAR and 5 critters


In my humble opinion, we're starting to degrade from the topic. We're tasked
with a PAR and 5 Criteria with a set of Objectives to support.  We are not
selecting baseline proposals, nor are we creating a draft.  We do have
drafts of our required documents, and if you disagree with those, please
relate the discussion to those documents.  From the presentations that I
have seen, all PHY vendors are on record as stating that they believed it
was possible to transmit 10Gbps on Cat7 cabling. This is an extremely
important base to build from because it is the one point that everyone seems
to have bought into at one time or another. It is the basis from which the
10G PHY and multi-rate PHY were developed.

If an individual or group of individuals does not believe that this claim is
true and wish to start a separate standards development endeavour, they are
permitted to perform a call for interest at any time. Otherwise, the focus
of this group is for the development of a 10GBASE-T PHY, and involvement
means that you support the Study Group this effort.


Chair, 10GBASE-T SG

Sent from my BlackBerry.