How the brc communicates with the fbr, How the brc communicates with the fbr -12 – Verilink Red Zone Encryption (REMS) (880-502423-001) Product Manual User Manual
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Theory of operation
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Red Zone Encryption Management System (REMS) User Manual
How the BRC communicates with the FBR
As shown earlier in Figure 3 -1, REMS T1 Signal Partitioning, the
network 2 Kbps framing and 2 Kbps CRC-6 codes are inserted at the
BRC. The FBR code (originating at each FBR) is carried through to the
far-end FBR and is used to maintain REMS synchronization. The
encrypted FBR code is periodically interrupted across the network to
support the ANSI T1.403 PRM and AT&T 54016 message exchanges.
The BRC collects network performance data and provides a one-way
communication channel through the encryptor to the FBR. Far-end BRC
performance data is conveyed to the near-end BRC by means of a ANSI
T1.403 Performance Report Message (PRM), which is inserted into the
FBR code.
Table 3-1, Decoding the 4-bit Message Field, shows what happens to the
FBR code as it travels through the system from the far end to the near end.
For the purposes of this discussion, only one 4-bit data byte is analyzed.
The alpha references in the table correlate the FBR code with a specific
location on the network diagram, shown in Figure 3 -3, Network
performance data is collected in the Black Zone.