Command Reference Guide

3Com Router 5000 Family and Router 6000 Family alarm-threshold ● 15
Command Reference
alarm-threshold
Purpose Use the alarm-threshold command to configure the alarm thresholds on the
CT1/PRI interface as needed.
Use the undo alarm-threshold command to restore the default alarm threshold
values.
Syntax alarm-threshold los pulse-detection value
alarm-threshold los pulse-recovery value
alarm-threshold ais { level-1 | level-2 }
alarm-threshold lfa { level-1 | level-2 | level-3 | level-4 }
undo alarm-threshold
Parameters los
Sets a loss of signal (LOS) alarm threshold. Two LOS
alarm thresholds are available: pulse-detection for the
pulse detection duration threshold with LOS and
pulse-recovery for the pulse threshold with LOS.
ais
Sets the alarm threshold of alarm indication signal
(AIS). Two AIS alarm threshold options are available:
level-1 and level-2. If level-1 is specified, an AIS alarm
occurs when the number of 0s in the bit stream of an
SF or ESF frame is less than or equal to 2. If level-2 is
specified, an AIS alarm occurs when the number of 0s
is less than or equal to 3 in the bit stream of an SF
frame or less than or equal to 5 in the bit stream of an
ESP frame.
lfa
Sets the loss of frame align (LFA) alarm threshold. Four
threshold options are available: level-1, level-2, level-3,
and level-4. If level-1 is specified, an LFA alarm occurs
when two of four frame alignment bits are lost. If
level-2 is specified, an LFA alarm occurs when two of
five frame alignment bits are lost. If level-3 is specified,
an LFA alarm occurs when two of six frame alignment
bits are lost. Level-4 applies only to ESF frames; an LFA
alarm occurs when four consecutive ESF frames have
errors.
Default The threshold of pulse-detection ranges from 16 to 4,096 pulse intervals and defaults
to 176.
The threshold of pulse-recovery ranges from 1 to 256 and defaults to 22.
If the number of the pulses detected during the total length of the specified pulse
detection intervals is smaller than the pulse-recovery threshold, a LOS alarm occurs.
By default, level-1 AIS alarm threshold applies.