3com MSR 20-20 참조 매뉴얼
250
C
HAPTER
15: T1-F I
NTERFACE
C
ONFIGURATION
C
OMMANDS
ft1 alarm-threshold
Syntax
ft1 alarm-threshold { ais { level-1 | level-2 } | lfa { level-1 | level-2 | level-3 | level-4 }
| los { pulse-detection | pulse-recovery } value }
| los { pulse-detection | pulse-recovery } value }
undo ft1 alarm-threshold
View
T1-F interface view
Parameter
ais: Sets the alarm threshold of alarm indication signal (AIS), which can be level-1
and level-2.
and level-2.
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The level-1 keyword specifies to generate an AIS alarm when the number of 0s
in the bit stream of an SF or ESF frame is less than or equal to 2.
in the bit stream of an SF or ESF frame is less than or equal to 2.
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The level-2 keyword specifies to generate an AIS alarm 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.
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.
By default, level-1 AIS alarm threshold applies.
lfa: Sets the loss of frame align (LFA) alarm threshold, which can be level-1,
level-2, level-3, and level-4.
level-2, level-3, and level-4.
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The level-1 keyword specifies to generate an LFA alarm when two of four
frame alignment bits are lost.
frame alignment bits are lost.
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The level-2 keyword specifies to generate an LFA alarm when two of five
frame alignment bits are lost.
frame alignment bits are lost.
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The level-3 keyword specifies to generate an LFA alarm when two of six frame
alignment bits are lost.
alignment bits are lost.
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The level-4 keyword applies only to ESF frames. It specifies to generate an LFA
alarm when errors are detected in four consecutive ESF frames.
alarm when errors are detected in four consecutive ESF frames.
By default, level-1 LFA alarm threshold applies.
los: Sets a loss of signal (LOS) alarm threshold, which can be pulse-detection (for
the pulse detection duration threshold with LOS) and pulse-recovery (for the
pulse threshold with LOS).
the pulse detection duration threshold with LOS) and pulse-recovery (for the
pulse threshold with LOS).
The threshold of pulse-detection, in units of pulse intervals, ranges from 16 to
4,096 and defaults to 176.
4,096 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. For example, if the two thresholds take their defaults, a LOS alarm is
created if the number of pulses detected within 176 pulse intervals is less than 22.
detection intervals is smaller than the pulse-recovery threshold, a LOS alarm
occurs. For example, if the two thresholds take their defaults, a LOS alarm is
created if the number of pulses detected within 176 pulse intervals is less than 22.
Description
Use the ft1 alarm-threshold command to set LOS, AIS, or LFA alarm thresholds
on the T1-F interface.
on the T1-F interface.