Verilink Red Zone Encryption (REMS) (880-502423-001) Product Manual User Manual
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Theory of operation
3-8
Red Zone Encryption Management System (REMS) User Manual
6.
As the near-end DTE transmits its D4/ESF framed signal, the near-
end FBR extracts information about the location of the D4/ESF
framing bit.
7.
The near-end FBR sends an FBR code that is aligned with the DTE
framing. This means, actually, that the FBR code is inserted into the
DTE framing bit position.
The far-end FBR identifies the FBR and BRC frame bit positions and
calculates an offset count.
8.
The near-end FBR repositions the DTE framing bit, which contains
the FBR code, by an amount equal to the offset count. Only the
framing bit itself is repositioned, and the end-to-end (encode/decode)
delay of the entire signal is a maximum of one bit. The FBR code
and BRC framing bits now correspond to the same time slot.
Time
I
BRC
DTE
F
I = BRC inserted bit
F = D4 framing bit
Time
I
BRC
DTE
F
FBR code
FBR
offset = x
I = BRC inserted bit
F = D4 framing bit
FBR = FBR code
F
0
1
2
3
191
0
1
2
F
3
191
offset = x