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[10GBASE-T] RE: [10GBT-Modeling] Reflections


Only Lord God Almighty knows the future with certainty.
To us mortals however, history is a helpful aid (no guarantees)
in predicting the future. When the folks were working on the 1000BASE-T 
standard the building blocks, required for 1000BASE-T AFE, in
one form or the other existed. In case of ADC, among others, see for 

C. W. Moreland, "An 8b 150MS/s serial ADC" ISSCC 1995 (ENOB=7-bit)

If you survey the last four years of ADC publications at ISSCC
(including 2003), where people are showing off their latest and 
greatest achievements, you'll not find any giga-hertz, Nyquist ADC 
with ENOB > 6.5-bit.

Bill I have learned my lesson never to say never; but this one sure is a 
tough one.


Joseph N. Babanezhad
Plato Labs.

> Joseph
> Will it exist when the standard is complete?
> Bill
> -----Original Message-----
> From: Joseph Babanezhad []
> Sent: Friday, February 28, 2003 12:18 PM
> To:;;
> Subject: Re: [10GBT-Modeling] Reflections
> Dear George Eisler,
> With all due respect some how I get the feeling that you are rushing 
> the standardization process. I remember during one of the conference 
> calls, prior to 10GBASE-T CFI, you were telling us not to get into 
> details because they'll be addressed in the SG. Now we read that we 
> should not do that at SG either and postpone it to Task Force! On 
> the reflector we are discussing some of the fundamental issues that 
> can make or break this whole process. In my mind it is fair to make 
> sure that before we get a lot more involved at least we do some sort 
> of bottom-line analysis to see if this thing is feasible or not. If 
> not what are the parameters that can be modified.
> You mentioned:
> > On the other hand, you will agree that the levels of sophistication 
> > in analysis and implementation of DSP based systems has also 
> > increased dramatically since 1997, when GigT started in earnest.
> DSP ALWAYS needs AFE in front of it. The DSP-based 10GBASE-T solution
> requires such a performance from AFE that does not exist today!
> Regards,
> Joseph N. Babanezhad
> Plato Labs.
> > Guys,
> > 
> > Nice to hear from a lot of the old crew that created the 1000BASE-T 
> > standard. I think that you can all take a bow, judging from what is 
> > happening in the market and the remarkable improvements in 
> > implementations achieved in three short years. But no good deed goes 
> > unpunished, as they say, so you guys earned the job (and created the 
> > need for) taking the next step up. Without a doubt, there are big 
> > jumps in the performance demanded and we don't have the luxury that 
> > 1000BASE-T enjoyed, namely the introduction of coding into the 
> > design. That has been done already. This time around, we have to 
> > take advantage of the residual capacity of the cabling, which we 
> > barely touched.  
> > 
> >  On the other hand, you will agree that the levels of sophistication 
> > in analysis and implementation of DSP based systems has also 
> > increased dramatically since 1997, when GigT started in earnest.
> > 
> > While I enjoyed fond memories of your recollections of what we knew 
> > (or suspected) then and what we added later when we got smarter, it 
> > strikes me that that history is relatively immaterial today. That 
> > was then and our current circumstances are quite different. We now 
> > need to agree in the study group that it is feasible to do 10Gig on 
> > some form of twisted pair cabling at the desired length and go on to 
> > form a Task Force to do the hard work of coming to agreement on the 
> > precise details of the signaling and channel specifications. 
> > 
> > It is clear that the channel specifications as written in 11801 will 
> > have to be modified and expanded for our use and installation 
> > qualification test parameters will have to be defined. This is more 
> > or less what happened for 1000BASE-T and seems to me to be a normal 
> > and reasonable step. After all, why should the cabling industry be 
> > expected to have already characterized cabling for the use of a 
> > standard for which we are still in the Study Group phase? As for 
> > installed cabling, we will see whether or how it may be qualified 
> > for 10G as part of our effort.
> > 
> > I look forward to our meeting in Dallas and hope that we can get to 
> > work on a PAR draft there.
> > 
> > George Eisler
> --
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