EXFO FTB/IQS-85100G Packet Blazer for FTB-500/IQS-600 - Manual (Page 209)

Test Results
Packet Blazer 199
Alarms/Errors

RDI-L (Remote Defect Indication - Line) - SONET
MS-RDI (Multiplex Section - Remote Defect Indication) - SDH
RX: Bits 6, 7, and 8 of the K2 byte contain the “110” pattern in five
consecutive frames.
TX: Generates a “110” pattern for the bits 6, 7 and 8 of the K2 byte.
Errors

FAS-S (Frame Alignment Signal - Section) - SONET
RS-FAS (Regeneration Section - Frame Alignment Signal) - SDH
RX: At least one A1 or A2 byte of the FAS word is in error.

B1 (BIP-8, Bit-Interleave Parity - 8 bits)
RX: Indicates a Section (SONET) / Regeneration Section (SDH) parity
error by performing a routine even-parity check over all frames of the
previous STS-n/STM-n signal (located in the first STS-1/STM-1 of an
STS-n/STM-n signal).

B2 (BIP-8, Bit-Interleave Parity - 8 bits)
RX:

SONET: Indicates a Line parity error by performing an even-parity
check over all bits of the LOH and SPE of the previous frame
(located in every STS-1 of an STS-n signal).

SDH: Indicates a Multiplex Section parity error by performing an
even-parity check over all bits (except those in the RSOH bytes) of
the previous frame of a STM-N signal.

REI-L (Remote Error Indicator - Line) - SONET
MS-REI (Multiplex Section - Remote Error Indicator) - SDH
RX: The M0, M1, or the combination of both M0 and M1 bytes indicate
that one or more BIP violations have been detected. Refer to M0 or M1
(SONET) on page 295 for more information.