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Perhaps a difficult number to remember, but with the +- 100ppm tolerance
and a bit rate that needs only to fit within about 200ppm of the nominal
SONET number we should be able to choose a round number with 4 digits in it.


As I understand the presentations in Montreal on speed,
a strong advantage of choosing this OC-192 payload rate is
to transport the signal over SONET OC-192 equipment.  This would
be from a "10Gb/s Ethernet" port out to SONET gear, which is really
a PMD external interface rather than a definition for the MAC/PLS interface
and data rate.

Given a raw continuous bit stream at the PMD, some scheme for 
framing packets would be needed.  10M used a carrier, 100M used coding,
1000M used coding.  Using coding where the PMD speed is fixed at 9.58Gb/s
would mean a further speed reduction (probably 10-20%) at the MAC/PLS
The discussion at the meeting has already started to consider ways of
the useful throughput at the MAC/PLS below the data clocking rate.  An
alternative framing scheme presented to HSSG, which has a smaller throughput
reduction, requires a packet length header -- a departure from previous 802

In considering the advantage of leveraging SONET OC-192 transport
we should also consider the issues which come up in actually getting
the hoped-for benefits.  It would also be worthwhile to carefully consider
what volume forecasts for the OC-192 components can be documented, in
evaluating the advantage to be gained.  Counting IEEE802.3 10Gb/s data
ports (however the definition works out) to get 2 million ports sounds
good, but I found the forecast of 2,000,000 OC-192 ports in 2000 rather