Patton electronics 6511RC, Administrator'S Reference Manual

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15 • SDH Model 6511RC Switch Matrix Administrators’ Reference Guide
136 Alarm Status
Figure 71. SDH Overview window—Alarm Status section
Sections, Lines, and Paths . Between a pair of SDH multiplexers, an SDH circuit may comprise multiple cable
segments connected by intermediate devices such as signal repeaters and add-drop multiplexers (See figure 61).
A cable segment with a regenerator at one or both endpoints is called a Section. A set of cable segments with an
add-drop multiplexer at one or both endpoints is called a Line.An SDH circuit with full-service multiplexers at
both endpoints is called a Path.
Figure 72. Section, path, and line within an SDH circuit
Section alarm
If an alarm is present in the SDH section, the indicator will change from green to red. Clicking on the icon will
take the user to the SDH Section STATUS ALARMS page (see
figure 73 ). A section alarm is activated if LOS
(loss of signal), LOF (loss of framing), or both are detected by the SDH interface.
Figure 73. SDH Section STATUS ALARMS window
Section LOS
The LOS alarm is activated when no transitions are detected on the incoming signal (before descrambling).
The LOS condition is detected upon observing 2.3 to 100 microseconds of no transitions. The LOS alarm is
cleared after a 125 microsecond interval (one frame) during which no LOS defect is detected.
SDH
Multiplexer
Regenerator Regenerator
SDH
Multiplexer
Section Section Section Section
Line Line
Path
Add-Drop
Multiplexer