EXFO FTB-8100 Series, User Manual

Page: 388 / 518

System Tab
376
FTB-8100 Series Transport Blazer
Clock Synchronization
Alarm Analysis
Note:
AIS and LOF alarms are not available for 2MHz clock.
³
LOS (Loss Of Signal): The LOS alarm indicates absence of an input
signal or an all-zeros signal is received.
³
AIS (Alarm Indication Signal): The AIS alarm is declared when an
unframed all-ones signal is received.
³
LOF (Loss Of Frame):
For DS1:
The LOF alarm indicates that there was no valid framing
pattern for 40 milliseconds and there was at least one OOF error during
this period.
³
With SF Framing: The Loss-of-Frame condition will be assumed
when 2 terminal frame and/or signaling frame errors in 5
consecutive frames have been received.
³
With ESF Framing: The Loss-of-Frame condition will be assumed
when 2 FPS frame errors in 5 consecutive frames have been
received.
For E1 : The LOF alarm indicates that three consecutive incorrect
frame alignment signals have been received.