EXFO FTB-8510B Guia Del Usuario página 971

Error Analysis
B2 (BIP-Nx24, Bit-Interleave Parity - Nx24 bits): The B2 error 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.
MS-REI (Multiplex Section - Remote Error Indicator):
For STM-0e: The MS-REI error is declared the M1 byte located in the
STM-1 channel 1 (first timeslot) indicates that one or more BIP
violations have been detected.
SONET/SDH Application
M1, bits
234 5678
000 0000
000 0001
000 0010
:
000 1000
000 1001
:
111 1111
SDH Tabs
Multiplex Section RX (SDH)
Indicates
0 BIP violation
1 BIP violation
2 BIP violations
:
8 BIP violations
0 BIP violation
:
0 BIP violation
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