RE: [EFM] Minutes of P2MP Optics conference 22nd Aug 20002
If I am not mistaken, your presentation assumed equal full attempted
utilization by all ONUs. Also, I thought that the FEC efficiency was much
lower, the FEC overhead percentage was much higher, particularly for the
smaller size frames.
At 01:07 PM 8/23/2002 -0400, Ajay Gummalla wrote:
> I had made a presentation in the last EFM meeting addressing
>exactly this issue. I broke down the overhead into its
>components and did a performance analysis.
>You can find the presentation at the following URL:
>Hope this helps answer your questions.
> > -----Original Message-----
> > From: firstname.lastname@example.org
> > [mailto:email@example.com]On Behalf Of
> > Thomas.Murphy@xxxxxxxxxxxx
> > Sent: Friday, August 23, 2002 12:55 PM
> > To: gkramer@xxxxxxxxxxx; Thomas.Murphy@xxxxxxxxxxxx;
> > firstname.lastname@example.org
> > Subject: AW: [EFM] Minutes of P2MP Optics conference 22nd Aug 20002
> > Hi Glen,
> > Thanks for the reply. Would it be possible to formulate
> > the statements below into an Excel data-sheet which could then
> > be used as a basis for discussion? I know that there has been some
> > work in this direction and my hope is to generate one tool which
> > has been accepted by the majority and can be used by all.
> > Regards
> > Tom
> > -----Ursprüngliche Nachricht-----
> > Von: Glen Kramer [mailto:gkramer@xxxxxxxxxxx]
> > Gesendet am: Freitag, 23. August 2002 18:44
> > An: Thomas.Murphy@infineon.com; email@example.com
> > Betreff: RE: [EFM] Minutes of P2MP Optics conference 22nd Aug 20002
> > Tom,
> > This is to address action item #2 from the minutes.
> > 2. Efficiency model based on guard bands and traffic type - P2MP group?
> > There are 3 types of overhead (or bandwidth loss):
> > 1. Cycle overhead. This is overhead used by guard bands (including CDR).
> > It is measured as a number of guard bands in one cycle. This number at
> > least equal to the number of ONUs, but may be even larger if we grant
> > per LLID and there are multiple LLIDs per ONU.
> > 2. Slot overhead. This overhead arises when granted slot does not take
> > into account frame delineation in a buffer. Since frames cannot be
> > fragmented, a frame that doesn't fit in the remainder of a slot will be
> > deferred to next slot (in next cycle), leaving current slot
> > underutilized.
> > The size of unused slot remainder depends on frame size distribution.
> > This distribution for today's traffic is known and there exist formula
> > to calculate this unused remainder (for the case when assigned slot size
> > has no correlation to the frame sizes).
> > Few protocol proposals consider how to eliminate unused slot remainder
> > completely, but it looks like it will require changes to the frame
> > format. P2MP group is still debating about it.
> > 3. Frame overhead. That includes IFG and headers. Nothing we can do
> > about it.
> > Glen
> > > -----Original Message-----
> > > From: firstname.lastname@example.org
> > [mailto:owner-stds-802-3-
> > > efm@xxxxxxxxxxxxxxxxxx] On Behalf Of Thomas.Murphy@xxxxxxxxxxxx
> > > Sent: Friday, August 23, 2002 1:57 AM
> > > To: email@example.com
> > > Subject: [EFM] Minutes of P2MP Optics conference 22nd Aug 20002
> > >
> > > Hello All,
> > >
> > > First off I apologise for sending this mail to the
> > > EFM reflector, however, a number of issues arose which
> > > are relevant for other groups.
> > >
> > > The next phone conference is planned for next Thursday
> > > at the old time of 11:00 Eastern
> > >
> > > Regards
> > >
> > > Tom
> > >