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Re: Specific PMD support of XAUI/XGXS




Jaime,

It was a simple question. I'll try again:

XAUI/XGXS addresses PMD independence, implementation flexibility, and signal
integrity by separating the intra-enclosure jitter domain from the
inter-enclosure jitter domain. At 10 Gbps, from the Reconciliation Sublayer,
signals and clocks cannot travel more than several inches across proposed
interfaces like the XGMII. XAUI/XGXS extends this distance (maybe that's where
the word "extender" relates to). 

So the question is: Is your PAM5/4WDM proposal compatible with the proposed
XAUI/XGXS? 

If the answer to the above question is NO. Then: Are you proposing your own
XGMII extender which is specific to only your PAM5/4WDM proposal?

I'm only asking this because you do say in your original note that you are "very
open and flexible with respect to supporting /A/,/K/, etc.."

Best Regards,
Rich
   
--

Jaime Kardontchik wrote:
> 
> Rich Taborek wrote:
> 
> > Jamie,
> >
> > Are you saying that your PAM5/4WDM proposal will not be compatible with
> > XAUI/XGXS? Please clarify.
> >
> > Best Regards,
> > Rich
> >
> > --
> 
> Rich,
> 
> Please, do not put in my mouth things that I did not say.
> I repeat below what I said before and I leave to others
> to fight the XAUI/XGXS/etc wars:
> 
> >
> > I am very open and flexible with respect to supporting /A/,/K/, etc..
> > However, I would like to point out that these are completely
> > unnecessary in my proposal "PAM-5 4-WDM at 1.25 Gbaud".
> >
> > Jaime
> 
> Jaime E. Kardontchik
> Micro Linear
> San Jose, CA 95131
> 
> >
> >
> > Jaime Kardontchik wrote:
> > >
> > > Rich Taborek wrote on Friday 00:26, March 17:
> > >
> > > >
> > > > .............. A WWDM or Parallel Optics PMD
> > > >  requires its PCS to support /A/, /K/, and /R/ to perform synchronization,
> > > > deskew, alignment and clock tolerance compensation. This information
> > > >  must indeed be transported out through the PMD to enable the remote
> > > > PCS receiver to perform all of the latter functions.
> > >
> > > Rich,
> > >
> > > I am very open and flexible with respect to supporting /A/,/K/, etc..
> > > However, I would like to point out that these are completely
> > > unnecessary in my proposal "PAM-5 4-WDM at 1.25 Gbaud".
> > >
> > > I do follow exactly the same synchronization steps that you
> > > mention in Albuquerque's presentation, slide # 15:
> > >
> > >     "4-lane link synchronization is a 5 step process
> > >          1-4 acquire sync on all 4 lanes individually
> > >         5 align/deskew synchronized lanes "
> > >
> > > Since I use the 1000BASE-T PCS instead of the 1000BASE-X
> > > PCS (8b/10b), the only difference is that each lane has its
> > > own 1000BASE-T PCS clocked at 312.5 MHz (instead of the
> > > 8b/10b coder) and a SERDES clocked at 1.25 GHz (instead
> > > of 3.125 GHz).
> > >
> > > The SERDES takes the four PAM-5 symbols generated by
> > > the 1000BASE-T PCS every 312.5 MHz clock cycle and
> > > delivers them serially to the PMD. Byte sync at the receiver
> > > is performed using the IDLE properties of the 1000BASE-T
> > > PCS. Lane alignment is trivial once you performed byte
> > > sync on the individual lanes.
> > >
> > > Jaime
> > >
> > > Jaime E. Kardontchik
> > > Micro Linear
> > > San Jose, CA 95131
> > > email: kardontchik.jaime@xxxxxxxxxxx
> >
> > -------------------------------------------------------
> > Richard Taborek Sr.                 Phone: 408-845-6102
> > Chief Technology Officer             Cell: 408-832-3957
> > nSerial Corporation                   Fax: 408-845-6114
> > 2500-5 Augustine Dr.        mailto:rtaborek@xxxxxxxxxxx
> > Santa Clara, CA 95054            http://www.nSerial.com
                                   
------------------------------------------------------- 
Richard Taborek Sr.                 Phone: 408-845-6102       
Chief Technology Officer             Cell: 408-832-3957
nSerial Corporation                   Fax: 408-845-6114
2500-5 Augustine Dr.        mailto:rtaborek@xxxxxxxxxxx
Santa Clara, CA 95054            http://www.nSerial.com