VeEX RXT3900, User Manual

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For the RX label, enable or disable the Payload Mismatch (PLM) Alarm
TX C2 [HP]
V5 [LP Path]: Path signal label
Program the TX and RX label by editing the hexadecimal value or by using the convenient drop-down menu
selection
For the RX label, enable or disable the Payload Mismatch (PLM) Alarm
TX V5 [LP]
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10.1.7 APS Testing
This function measures the Automatic Protection Switching (APS) limits of the network. APS applies only to the Multiplex sections
of a SDH network and enables network elements to re-route traffic to a backup circuit in the event of network failure or problems.
The protection mechanism is coordinated by the K1 and K2 bytes in the Multiplexer Section Overhead.
APS Standards
The principles and protocols of APS in SDH networks are defined in ITU-T G.783 and G.841 and Bellcore GR-253
recommendations for Linear and Ring network architectures respectively. According to recommendations, the re-routing of the
signal has to occur within 50ms. Protection switching is initiated as a result of one of the following conditions:
“Hard” Failure (SF) condition – Loss of Signal (LOS), MS-AIS, BER > 1 x 10
-3
.
“Soft” Failure (SD) condition – Signal degradation when BER exceeds a predetermined threshold. Normally over a
provisioned range of 1 x 10
-5
to 1 x 10
-9
.
RXT-3900 e-Manual D07-00-111P Rev A00