lpDS3LofAlarm 1.3.6.1.4.1.562.2.4.1.12.5.16.1.2

This attribute displays whether a Loss Of Frame (LOF) alarm state has been entered. An LOF alarm state is entered when Severely Errored Frame (SEF) defects have been observed and accumulated for a period of 2.5 seconds +/- 0.5 seconds. A SEF defect is detected when 3 (or more) out of 16 (or fewer) F-bits are in error, or one (or more) M-bits in two (or more) out of four (or fewer) consecutive M-frames are in error. If the LOF defects are intermittently occurring, the LOF 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. The DS3 component goes into an operational state of disabled until the LOF alarm condition is cleared. The condition is cleared when framing has been achieved for a period of 10 seconds +/- 0.5 seconds. As long as SEF defects are detected, the node also transmits the far-end SEF/AIS defect indicator over the outgoing line. When not running in C-Bit Parity mode, the txRai attribute is also set to on when transmitting the far-end SEF/AIS defect indicator on the outgoing line. The lofAlarm attribute is always set to off when the component has been locked and left offline.