as another example a 10 bit field could indicate the last 10 sefm in this example if the bit field indicated 111111100 this would show that there was a sef defect for the last 2 sef measurements prior to exiting showtime this means that the last 2 sync symbols prior to exiting showtime did not contain the expected content as another example a 10 bit field could indicate the last 10 insm prior to exiting showtime in this example if the bit field indicated 1100000000 this would show that the last 8 dmt symbols prior to exiting showtime were severely degraded due to impulse noise or some other problem for example the initialization or diagnostic mode message may contain a bit field that indicates the lastsym and or the closd and or the csefd etc for example a s 24 bit field could indicate the lastsym i e the symbolcount of the last dmt symbol received or transmitted prior to exiting showtime as another example a n21 u00d7 s bit field could indicate the closd the symbolcounts of n21changes of the los defect state if n21 5 and s 24 then the closd parameter would contain five 24 bit symbolcount values with each symbolcount indicating a change in the los defect state as yet another example a n22 u00d7 s bit field could indicate the csefd the symbolcounts of the last n22 changes of the los defect state if n22 5 and.