Man-Machine T1 maintenance interface software 227
When the first level of severityis reached (alar m level1), the MMI does
the following:
•activates the external alarm hardware
•lights the appropriate LED on the faceplate (either RED ALARM or
YELLOW ALARM)
•displays an alarm message on the MMI terminal
•creates entry in the alarm log
When the second level of severity is reached (alarm level2), the MMI
performs all of the same functions as alarm level 1, andin addition, forces
the Lineside T1 card to enter trunk processing mode. In this mode, the
terminal equipment sends either "on-hook" or "off-hook" signals for all 24
ports to the CS 1000M, and Meridian 1, depending on how the dip switch for
trunk processing was set (dip switch #2, position #6).
If the MMI detects T1 link failures forany of the remainder of the conditions
monitored (out of frame condition, loss of signal condition, and blue alarm
condition), the Lineside T1 card automatically performs all alarm level 2
functions. The MMI also sends a yellow alarm to the distant end CPE or
CSU.
Alarms can be configured to self-clear or not self-clear when the alarm
condition is no longer detected.
All alarms activated produce a record in an alarm log. The alarm log
maintains records for the most recent 100 alarms and can be displayed,
printed and cleared. The alarm log displays or prints the alarms listing
the most recent first in descending chronological order. The alarms are
stamped with the date and time they occurred.
MMI activates alarms for the following T1 link conditions:
•excessive bit error rate
•frame slip errors
•out of frame condition
•loss of signal condition
•blue alarm condition
The alarms are activated in response to pre-set thresholds and error
durations. Descriptions of each of these T1 link alarm conditions,
instructions on how to set alarm parameters, and access alarm reporting
can be found in "Alarm operation and reporting" (page 243).
Twolevels of alarm severity exist for bit errors and frame slip errors.
For these conditions, two different threshold and duration settings are
established.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23May 2008
Copyright© 2003-2008, Nor tel Networks
.