Avaya S8700 Maintenance Manual page 1332

Maintenance-Object Repair Procedures
Blue Alarm Inquiry Test (#139)
The Blue Alarm is a signal sent by the remote DS1 endpoint when it is
out-of-service. The Blue Alarm Inquiry test checks the blue alarm status of the
remote DS1 endpoint.
When the DS1 Interface circuit pack detects a Blue Alarm signal from the remote
DS1 endpoint, the circuit pack will transmit a Yellow alarm to the remote DS1
endpoint and send a BLUE ALARM message to the maintenance software. When
the Blue alarm is confirmed, the maintenance software places all trunks of the
DS1 Interface circuit pack into the out-of-service state. The inquiry test will be run
every 10 minutes until the Blue alarm is cleared.
The DS1 Interface circuit pack takes 2 seconds to recognize and report a Blue
alarm and 16 seconds to recognize and report the resolution of a Blue alarm.
When the Blue alarm is cleared, the DS1 Interface circuit pack stops transmitting
the Yellow alarm and places the trunks back into the service state before the Blue
alarm occurs.
Line Loopback Alarm
The Line Loopback (LLB) is used by the remote DS1 endpoint to put the ICSU or
DS1 into a loop-back mode. When the ICSU or DS1 Board is in the LLB mode,
the arriving bit pattern is regenerated and sent back. Line Loopback (LLB) Alarm
is activated when the in-band activate LLB bit pattern has been arriving
continuously for 5 seconds on the DS1 line. LLB is deactivated when the in-band
deactivate LLB bit pattern has been arriving continuously for 5 seconds on the
DS1 line.
Since LLB is a maintenance condition rendering all DS0 channels unavailable for
signaling or bearer traffic, maintenance software treats this the same as a Blue
Alarm.
Payload Loopback Alarm
The Payload Loopback (PLB) is used by the remote DS1 endpoint to put the
switch DS1 into a loop-back mode. PLB Alarm is activated when a network
protocol activate bit pattern arrives over the 4-Kbps ESF data link on the DS1 line.
PLB is deactivated when a network protocol deactivate bit pattern arrives over the
4-Kbps ESF data link on the DS1 line.
Since PLB is a maintenance condition rendering all DS0 channels unavailable for
signaling or bearer traffic, maintenance software treats this the same as a Blue
Alarm.
8-610 Issue 1 May 2002 555-233-143