EXFO FTB-8510B Guia Del Usuario página 815

Error Analysis
Possible errors that can be detected are:
FAS (Frame Alignment Signal): Indicates the FAS bits in error.
MFAS (Multiframe Alignment Signal): Indicates the MFAS bits in error.
OTU-BIP-8 (OTU - Bit Interleave Parity-8): Indicates the SM BIP-8
mismatch between the received value and locally computed value
(0 to 8).
OTU-BEI (OTU - Backward Error Indication): Indicates SM BEI errors
received from the DUT (value 0 to 8).
0000
0001
0010
0011
0100
SONET/SDH Application
OTU BEI bits
BIP violations
(1234)
0
1
2
3
4
ODUk BEI bits
(1234)
0101 5
0110 6
0111 7
1000 8
1001 to 1111 0
OTN Tabs
OTU RX
BIP violations
165