Re: PMD discussion
Edward,
The WAN PHY cannot use 8b10b after the SONET framing because the
packet delimiters are buried in the scrambling. Without packet
delimiters, there is no where to put the commas for use in code-
group synchronization.
For SONET CWDM, Paul has offered the SUPI proposal which stripes
a byte of the SONET frame over each of the 4 lanes. The serial
SONET framed WAN PHY operates at a data rate of 9.95328 Gbaud.
Each of the 4 lanes operates at 1/4 of this rate or 2.48832
Gbaud. The re-alignment logic works on the A1/A2 framing, both
for byte sync and lane sync.
I hope this helps clarify how the coding works in Paul's proposal.
For more details, see his proposal directly:
http://grouper.ieee.org/groups/802/3/ae/public/may00/bottorff_1_0500.pdf
Ben
Edward Chang wrote:
>
> Seto:
>
> Paul's May presentation does not exclude 8B/10B. I specifically asked him
> at the time of presentation. How to use 8B/10B for C/WWDM WAN-PHY
> application. Paul replied that he is not familiar with 8B/10B C/WWDM
> application; as a result, he did not know how to draw 8B/10B C/WWDM
> application on the his page 3, Component chart. He mentioned that SUPI can
> be extended to PCS with 8B/10B code.
>
> It is same as in the CWDM proposal, which I drew the reference model to show
> how CWDM to use 8B/10B and adopt XAUI to extend PCB runs.
>
> For WAN_PHY PMD, the PCS will be 8B/10B. WIS remains the same as proposed.
> It seems that the 16 bit WIS output will enter PMA (SERDES) through SUPI to
> be serialized into four serial/self clocking outputs to enter PMD (O/E).
> At the O/E output, there will be a WWDM to optically multiplex 4 serial data
> lines at 3.125 Gbps into one fiber for transmission.
>
> Regards,
>
> Edward S. Chang
> NetWorth Technologies, Inc.
> EChang@xxxxxxxxxxxxxxxx
> Tel: (610)292-2870
> Fax: (610)292-2872
>
> -----Original Message-----
> From: owner-stds-802-3-hssg@xxxxxxxx
> [mailto:owner-stds-802-3-hssg@xxxxxxxx]On Behalf Of Seto, Koichiro
> Sent: Monday, May 29, 2000 2:34 AM
> To: boazs@xxxxxxxxxxxx; rtaborek@xxxxxxxxxxx; stds-802-3-hssg@xxxxxxxx
> Subject: Re: PMD discussion
>
> [Date: 05/28/2000 From Seto]
>
> Yes, something called SUPI (Simple Universal PMD I/F) has been proposed by
> Paul Bottorff. See his presentation at IEEE802.3ae May interim. I assume
> this is a part of WAN PHY PMA.
>
> to Rich,
> I'd suggest that you give a new name for your 8B10B x 4ch coding scheme for
> WWDM which includes idle pattern randomization. Any idea?
>
> Seto
>
> >
> > Hi,
> > The 4-lane code for WDM is 8b/10b. However, what happens in the case of
> WAN
> > PHY?
> > Is there any proposal for line code (Over the Fiber) for WDM WAN PHY?
> >
> > > -----Original Message-----
> > > From: Rich Taborek [mailto:rtaborek@xxxxxxxxxxxxx]
> > > Sent: Monday, May 29, 2000 7:15 AM
> > > To: HSSG
> > > Subject: Re: PMD discussion
> > >
> > >
> > >
> > > Joel,
> > >
> > > There are no complete 4-lane serial proposals for WDM on the
> > > table which use a
> > > transmission code other then 8B/10B. The 8B/10B 4-lane serial
> > > proposals have
> > > been essentially stable for more than 6 months now. It's
> > > getting darn close to
> > > July, any other candidate transmission codes for WWDM need to
> > > get aired very
> > > soon.
> > >
> > > Best Regards,
> > > Rich
> > >
> > > --
> > >
> > > Joel Goergen wrote:
> > > >
> > > > Walter,
> > > >
> > > > I like the second better, but for clarity, I have a
> > > question .... for the
> > > > serial solution, my understanding is the thought is to use
> > > 64b66b on the
> > > > fiber. What is the general thought for wdm? Is it just
> > > 8b10b or is the
> > > > thinking in general that the line interface is 64b66b?
> > > >
> > > > Take care
> > > > Joel
> > > > -----------------------------
> > > >
> > > > Walter Thirion wrote:
> > > >
> > > > > First of all, thanks to everybody that presented PMD
> > > proposals at the last
> > > > > meeting. I've sent my presentation to David Law, so it
> > > should be available
> > > > > on the web site in the next couple of days.
> > > > >
> > > > > In listening to the discussion after my presentation and
> > > then going around
> > > > > and talking to people, it feels to me like we're starting
> > > to converge. Not
> > > > > there, yet, but making progress.
> > > > >
> > > > > The equipment manufacturers made it pretty clear they
> > > would like to see no
> > > > > more than 3 PMDs in the standard. The PMD vendors have
> > > some concern that
> > > > > using only 3 PMDs may sub-optimize certain objectives,
> > > however, they could
> > > > > support the 3 PMD position if it is made clear which 3
> > > PMDs the equipment
> > > > > oems want.
> > > > >
> > > > > Based on an informal straw poll and anecdotal evidence,
> > > my opinion is the
> > > > > first choice would be the set:
> > > > > ________________
> > > > > 850 nm WWDM
> > > > > 1310 nm WWDM
> > > > > 1550 nm Serial
> > > > > ________________
> > > > >
> > > > > If that set isn't feasible, then the 2nd most popular choice is:
> > > > > ________________
> > > > > 850 nm WWDM
> > > > > 1310 nm Serial
> > > > > 1550 nm Serial
> > > > > ________________
> > > > >
> > > > > Thoughts, feedback?
> > > > >
> > > > > Walt
> > > > > ___________________
> > > > > Walter Thirion
> > > > > Chair, IEEE 802.3ae PMD Sub-Task Force
> > > > > 301 Congress Ave.
> > > > > Suite 2050
> > > > > Austin, Texas 78701
> > > > > Voice: 512-236-6951
> > > > > Fax: 512-236-6959
> > > > > wthirion@xxxxxxxxxxxx
> > > > > ___________________
> > > >
> > > > --
> > > > Joel Goergen
> > > > Force10 Networks
> > > > 1440 McCarthy blvd
> > > > Milpitas, Ca, 95035
> > > >
> > > > Email: joel@xxxxxxxxxxxxxxxxxxx
> > > > Direct: (408) 571-3694
> > > > Cell: (612) 670-5930
> > > > Fax: (408) 571-3550
> > >
> > > -------------------------------------------------------
> > > 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
> > >
> >
--
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Benjamin Brown
Router Products Division
Nortel Networks
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Kilton Road
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