SDH Tabs
LOP RX (SDH, TU-3 path)
Alarm Analysis
TU-AIS (Tributary Unit - Alarm Indication Signal): The TU-AIS alarm is
declared when the H1 and H2 bytes contain an all-ones pattern in three
consecutive frames
TU-LOP (Tributary Unit - Loss Of Pointer): For non-concatenated
payloads, the TU-LOP alarm indicates that a valid pointer is not found
in N consecutive frames (where 8 ≤ N ≤ 10), or N consecutive NDFs
("1001" pattern) are detected.
LP-RDI (Tributary Unit - Remote Defect Indication): The LP-RDI alarm
is declared when bits 5, 6 and 7 of the G1 byte contain the "100" or
"111" pattern in five consecutive frames.
LP-TIM (Low Order Path - Trace Identifier Mismatch): The LP-TIM
defect indicates that none of the sampled path trace strings match the
expected message value. The LP-TIM alarm result is only available
when LP-TIM from J1 Trace section has been enabled.
LP-PLM (Low Order Path - Payload Label Mismatch): The LP-PLM is
declared upon receipt of five consecutive frames with mismatched VC
signal labels.
LP-UNEQ (Low Order Path - Unequipped): LP-UNEQ is declared when
the C2 bytes contain "00 H" in five consecutive frames.
ERDI-SD (Enhanced RDI - Server Defect): The ERDI-SD alarm is
declared when bits 5, 6 and 7 of the G1 byte contain the "101" pattern
in five consecutive frames.
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SONET/SDH Application