This attribute displays whether a LOS (Loss of Signal) alarm state is entered. An LOS alarm state is entered when LOS defects have been observed and accumulated for a period of 2.5 seconds +/- 0.5 seconds. An LOS defect is declared at the JT2 line interface when the input data is zero for 20 - 32 clock cycles. If the LOS defects are intermittently occurring, the LOS 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. An LOS failure alarm is cleared when the LOS defect is absent for a period of 10 seconds +/- 0.5 seconds. The JT2 port goes into an operationalState of disabled for the duration of the LOS alarm condition. While the port is in the LOS alarm state, the port also transmits the far-end RAI defect indicator on the out-going JT2 line.