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[EFM] Re: [EFM-Copper] Long Reach Copper Presentations in Vancouver




John,
I couldn't agree more.  I believe that this issue was raised in March in the
St. Louis meeting (the baseline meeting).  There was even a motion on it,
which was widely supported, but it didn't make the 75% mark.  

Perhaps, given the passage of time, and the now accepted position that IEEE
will wait for the selection of a line code by T1E1, such a motion should be
revisited.  But I suspect the people who voted against it before would do so
again, because their motivations were more philosophical than technical.
But who knows... 

As a side note, if such a position were adopted, then maybe EFM would not
have to wait for T1E1, and the schedule would free up...  Maybe that has
some value? 

Sincerely, 
Frank Effenberger






To: Behrooz Rezvani <brezvani@xxxxxxxxxx> 
Subject: [EFM] Re: [EFM-Copper] Long Reach Copper Presentations in Vancouver

From: John Farnbach <john.farnbach@xxxxxxxxx> 
Date: Thu, 19 Dec 2002 10:11:42 -0700 
CC: John.Egan@xxxxxxxxxxxx, barry.omahony@xxxxxxxxx,
millardo@dominetsystems.com, stds-802-3-efm-copper@ieee.org,
stds-802-3-efm@ieee.org 
References:
<9D975BDAF4ADD311AED80008C7915FD405CDAB65@xxxxxxxxxxxxxxxxxxxxxxxxxx>
<04d101c2a76c$033e5b40$c2dab4d3@PCLAPTOPKEMI> 
Sender: owner-stds-802-3-efm@majordomo.ieee.org 

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----
I'm a new kid on this block, so allow me a naive comment on the dialog about
ADSL vs SHDSL. 
I don't see why it is necessary in a practical sense to define any physical
layer at all for EFM.  referring to slide 19 of jackson_copper_1_0702.pdf,
why not simply define the EoDSL interface between the MAC and any PMD
capable of carrying a clear channel byte stream.  That would make EFM
future-proof to possible new DSL versions, it would provide a degree of
backwards compatibility, since many carriers will have already deployed ADSL
or SHDSL, and it will allow chip vendors the option of integrating the EoDSL
function in xDSL tranceiver chips. 

I guess I'm suggesting that the copper group just define both sides of
Jackson's EoDSL layer and stop there.  Let the PMD standards ensure that
they provide a compliant TPS-TC, which should only be a clear channel byte
stream. 

Best regards, 
John Farnbach