EXFO FTB-8500 Series for FTB-500 - Manual (Page 260)

WIS Tabs
246 FTB-8500 Series and FTB-8120NGE/8130NGE
WIS RX

REI-L (Remote Error Indicator - Line): The REI-L error is declared
when bits 5 through 8 of the M0 byte contain one pattern from the
following binary range: “0001” through “1000” (1 to 8) (located in the
first STS-1 of an STS-n signal).

REI-P (Remote Error Indicator - Path): The REI-P error is declared
when bits 1 through 4 of the G1 byte contain one pattern from the
following binary range: “0001” through “1000” (1 to 8) (located in every
STS-1 of an STS-n signal).
Alarm Analysis

SEF (Severely Errored Framing): A SEF defect indicates that a
minimum of four consecutive errored framing patterns are received.

LOF (Loss Of Frame): A Loss Of Frame alarm indicates that a Severely
Error Framing (SEF) defect on the incoming SONET signal persists for
at least 3 milliseconds.

AIS-L (Alarm Indication Signal - Line): The AIS-L alarm is declared
when bits 6, 7 and 8 of the K2 byte contain the “111” pattern in five
consecutive frames.

RDI-L (Remote Defect Indication - Line): The RDI-L alarm is declared
when bits 6, 7, and 8 of the K2 byte contain the “110” pattern in five
consecutive frames.

AIS-P (Alarm Indication Signal - Path): The AIS-P alarm is declared
when the H1 and H2 bytes for a STS path contain an all-ones pattern in
three consecutive frames or more.

RDI-P (Remote Defect Indication - Path): The RDI-P alarm is declared
when bits 5, 6 and 7 of the G1 byte contain the “100” or “111” pattern in
ten consecutive frames.

LCD-P (Loss of Code-Group Delineation - Path): Indicates that the
signal synchronization has been lost and valid code-groups are no
longer being delineated from the received payload stream being
passed to the PCS.