EXFO FTB-800 Series for FTB-1 - Manual (Page 291)

Test Results
NetBlazer 281
Alarms/Errors
STS-x/AU-x
Alarms

AIS-P (Alarm Indication Signal - Path) - SONET
AU-AIS (Administrative Unit - Alarm Indication Signal) - SDH
RX: The H1 and H2 bytes contain an all-ones pattern in three
consecutive frames or more.
TX: Generates an all-ones pattern over H1, H2, H3, and SPE.

LOP-P (Loss Of Pointer - Path) - SONET
AU-LOP (Administrative Unit - Loss Of Pointer) - SDH
RX: A valid pointer is not found in N consecutive frames (where
8  N  10), or that N consecutive NDFs (“1001” pattern) are detected
(non-concatenated payloads).
TX: Generates a non-valid pointer.

UNEQ-P (Unequipped - Path) - SONET
HP-UNEQ (HP - Unequipped) - SDH
RX: The C2 byte contains “00 H” in five consecutive frames. Only
available when PLM-P/UNEQ-P / HP-PLM/HP-UNEQ is enabled (refer to
Labels on page 150).
TX: Generates an all-zeros pattern over POH and SPE.

H4-LOM (H4 - Loss Of Multiframe)
RX: For VT/TU structured optical frames, the system loss track of the H4
byte multiframe indicator sequence.
TX: Generates a wrong H4 byte multiframe indicator sequence.

TIM-P (Trace Identifier Mismatch - Path) - SONET
HP-TIM (HP - Trace Identifier Mismatch) - SDH
RX: J1 Trace doesn’t match the expected message value. Only
available when TIM-P/HP-TIM is enabled (refer to Traces (SONET/SDH)
on page 239).