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[EFM] OAM in Preamble Question

Hello All,

I found Mr. Suzuki's presentation on OAM in preamble interesting but had a
question that perhaps someone can answer.  It was understood that current
1000Base-X Gigabit implementations were a problem.  After all a 1000Base-X
device can transmit either 7 or 8 bytes of preamble.  But what about
1000Base-T.  If I understand it correctly 1000Base-T has two bytes allocated
for Start of Stream Delimiter (SSD1 + SSD2) on the transmit side and on the
receive side some implementations simply assume the first two bytes are
0x55.  This would there by make the amount of preamble not 8 but 6.

I would like to know if I'm off base with these remarks and if not how this
affects OAM in Preamble.


Al Braga
InterOperability Lab
University of New Hampshire