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Re: [8023-10GEPON] Presentation on FEC for 10G



Dear All, 

On item #3, I used the word "aligned" there very deliberately to suggest a
coordination of function, but not a determination of exact value.  

As Jeff suggests, code-word size (in absolute terms) is mainly associated
with coding gain (bigger is better) and coder complexity (bigger is
complicated).  What I am saying with item #3 is that whatever codeword size
we eventually target, then we figure out how to best package an integral
number of 66b blocks and/or MPCP time quanta into that size.  That's all.  

I agree with Jeff and Roger's email comments, that the coding gain and
algorithm is a somewhat orthogonal issue from the framing integration.  It
must be recognized, however, that the two need to be coordinated in the end.

 

Let me explore a slightly different question in front of the wide group: It
seems that everybody has been thinking about OOK signaling with block-codes
for FEC.  Do we all agree on this?  Even that is nontrivial to say, because
there are many non-block FEC codes and more complex signaling that we could
explore, if we had the inclination.  These could be interesting, in that
they could reduce the baud-rate on the line down to ~2.5Gbd levels, and that
puts us in a much cheaper PMD territory.  It's something to think about.

Sincerely,
Frank E.



-----Original Message-----
From: Jeff Mandin [mailto:Jeff_Mandin@PMC-SIERRA.COM] 
Sent: Thursday, August 17, 2006 8:16 AM
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: Re: [8023-10GEPON] Presentation on FEC for 10G

 Frank hi,

> .....
>  I think that there is some common support for the following basic
ideas: 
> 1. FEC should be applied at the very lowest layer (streaming-FEC).
> 2. FEC should be a mandatory part of the line code.  

Yes I agree on both of these points.

> 3. FEC codeword size should be aligned with the other EPON structure
sizes (such as 66b blocks and MPCP time quanta)

There are other considerations in selecting the codeword size that are
also important (maybe more important)  ie. coding gain and
implementation complexity.


> There are related topics that I don't think we've reached consensus
on: 
> a. Choice of basic FEC algorithm (e.g, RS, BCH, etc.) b. Line-rate
increasing versus MAC-rate reducing approach c. Code-rate and objective
gain values (some of these require collaboration with PMD specialists.) 

These items include what appear to be two distinct topics:  

            *  framing, and integration of FEC into line code
	*  the selection of the FEC algorithm, code rate etc. (probably
requires PMD collaboration and simulation work)

Since the two topics are somewhat orthogonal, I think it would be good
for us to deal with them separately.

PMC is preparing a FEC presentation for the interim as well, so we
welcome the opportunity to preharmonize.

BRs,

- Jeff Mandin


-----Original Message-----
From: Frank Effenberger [mailto:feffenberger@HUAWEI.COM] 
Sent: Wednesday, August 16, 2006 7:44 PM
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: [8023-10GEPON] Presentation on FEC for 10G

Dear All, 

I am interested in putting together a presentation on FEC for 10G
(serial) PONs.  Judging from the materials from the July meeting, I
think that there is some common support for the following basic ideas: 

1. FEC should be applied at the very lowest layer (streaming-FEC).
2. FEC should be a mandatory part of the line code.  
3. FEC codeword size should be aligned with the other EPON structure
sizes (such as 66b blocks and MPCP time quanta)

There are related topics that I don't think we've reached consensus on: 
a. Choice of basic FEC algorithm (e.g, RS, BCH, etc.) b. Line-rate
increasing versus MAC-rate reducing approach c. Code-rate and objective
gain values (some of these require collaboration with PMD specialists.) 

If there are people who are interested in working with me on a
presentation on these topic areas, please let me know.  

Sincerely,
Frank Effenberger







-----Original Message-----
From: Glen Kramer [mailto:glen.kramer@teknovus.com]
Sent: Friday, August 11, 2006 5:04 PM
To: STDS-802-3-10GEPON@listserv.ieee.org
Subject: [8023-10GEPON] presentations for September meeting

Dear colleagues,

It appears that our next meeting will take place on September 18th and
19th (Monday and Tuesday) and the High-Speed SG will meet on 20th and
21st, so there will be no overlap and interested people will be able to
attend both meetings.

The meeting venue has not been finalized yet. A venue should be
announced at least 30 days before the meeting, so expect the
announcement very soon.

Meanwhile, it is time to start working on presentations for the next
meeting.

There are many specific topics/features that we have to reach consensus
on: 

Downstream Wavelength
Upstream Wavelength
Power budgets
FEC: Optional or Mandatory
FEC Category: Stream-based vs. Frame-based other topics - anything that
is in scope of our PAR can be discussed. 

If you can think of any other topic not listed here, please propose it
on the reflector.


If you have opinion on any of these or other topics, make a presentation
with arguments in favor of it. Remember, a proposal should have > 75%
support to get accepted as a baseline. It is a good idea to circulate
proposals on the reflector and get feedback, and to enlist additional
supporters.  

Regards,
Glen