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From serial PMD call, 24 April; next week at later time




Verification of optical power under OMA definition
--------------------------------------------------
We had just received Juergen's email and not had time to assimilate it.  My
summary:
Our current definition means the relation between OMA and mean power can
vary by several (6-7) dB.
Juergen proposes a minimum mean power spec which would reduce that variation
to 5 dB.

My question is: would that change be acceptable (to PMD vendors)?
Would that change be valuable or sufficient (for network installers and
maintainers)?

Jitter-risetime trade off compatibility with triple trade off
-------------------------------------------------------------
I have done some spreadsheet investigation and have good news to report.
If we were to introduce a jitter-risetime trade off (for reasons of cost and
simplification) it would not be incompatible with the (wavelength/spectral
width/power) triple trade off.  It seems that "traded" jitters and risetimes
would give a very slightly relaxed triple trade off for narrower spectral
widths/lower powers than the default point, and an imperceptible difference
for wider spectral widths/higher powers.  To put it another way: these
things may not be mathematically quite orthogonal but turn out to have low
correlation.

So we are free to proceed with the jitter-risetime trade off on its own
merits, and evolve the triple trade off using the default jitter and
risetime.  

Notice that experimental verification of the model is still a task to be
done by the community; the discussion above doesn't impact that fact
significantly. 

Delay maximum
-------------
No issue seen with PMD.  PMA group need to confirm that they are OK too.
David Kabal to forward some background information to reflector.
Piers to comment against Cl. 51, 52 to get each to reference Cl. 44.3.

dB(OMA) vs. dB(OMA/2)?
----------------------
David Kabal's poll has voted for OMA and dB(OMA).

Only 11 commenting days to go!
------------------------------
Please copy your comments on Cl.52 to David Kabal to give him a head start.
Next meeting will be the last before the deadline, Saturday, 5 May 2001 at
12:00 midnight Pacific time.

Next meeting
------------
To avoid a clash with another standards meeting (OIF), next week's call will
start at:
4pm GMT = 5pm BST = 18:00 CET = 12 noon EDT = 9am PDT.
Usual phone # as the level of complaints about access has gone down.


Piers