VeEX RXT-6000e, User Manual

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AU Pointer Byte
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Line Layer / Multiplexer Section
B2 Byte (MS-BIP)
A 24-bit interleaved even parity code used to determine if transmission errors have occurred over the
Multiplexer Section
Its calculated over all the bits of the STM-1 frame except those in the Regenerator Section overhead
The computed checksum is placed in the MSOH of the following STM-1 frame
K1 Byte (APS-Linear)
Used to activate and deactivate the switching between the main and protection paths on a multiplexer section
APS message type conforms to ITU-T G.783 and Bellcore GR.253 for Linear network architectures
Bits 1-4 (G.783 Protocol)
1111 Lockout of protection
1110 Forced switch
1101 Signal fail, high priority (1:n only)
1100 Signal fail, low priority
1011 Signal degrade, high priority (1:n only)
1010 Signal degrade, low priority
1000 Manual switch
0110 Wait to restore
0100 Exercise
0010 Reverse request (bidirectional systems only)
0001 Do not revert
0000 No request
Other codes are unused
Bits 5-8 selects channel used by APS messages
0000 Null channel
0001 to 1110 Channels 1 thru 14
1111 Extra traffic channel
RXT-6200_RXT6000e_Module_Manual Page 124 of 387