This attribute indicates whether an AIS (Alarm Indication Signal)
alarm state has been entered. The AIS Alarm state is entered when
AIS defects have been observed and accumulated for 2.5 seconds
+/- 0.5 seconds. An AIS defect is detected after having received less
than 3 zeros in a 2048 bit period. If the AIS defects are
intermittently occurring, the AIS defect accumulator is decremented
at a rate of 1/10 of the incrementing rate (alarm integration ratio of
1/10), with all measurements based on a 200 ms polling cycle. This
tributary goes into an operationalState of disabled for the duration
of an AIS alarm state.
The AIS alarm state is cleared when AIS defects are absent for 10
seconds +/- 0.5 seconds.