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D Alarm Definitions
GDC 048R154-000
Overview
This appendix describes the DeskTop T1 DSU alarms that can appear
on the terminal interface Monitor screen Alarm Status display:
Network OOF
(Network Out of Frame)
Network LOS
(Network Loss of Signal)
Network USS
(Network Unavailable Signal State)
Network AIS
(Network Alarm Indication Signal)
Network BPVS
(Network Bipolar Violations)
Network CRCS
(Network Cyclic Redundancy Checksum)
Network RYEL
(Network Received Yellow Alarm)
Network LAD
(Network Low Average Density)
Config Error
(Configuration Error)
Network Alarms
Network Out Of Frame
A Network Out Of Frame (NETWORK OOF) alarm event occurs
when the DSU misses two out of four framing bits in the signal coming
from the network. The front panel OOF indicator reflects the current
status of DSU-to-network synchronization.
Network Loss Of Signal
A Network Loss of Signal (NETWORK LOS) alarm event occurs
when the DSU senses an absence of network signal. The absence of
signal for a time equivalent to 175 bits (± 75) is considered no signal.
The front panel LOS indicator reflects the current status of the network
signal condition.