DEFINITY Enterprise Communications Server Release 7
Maintenance for R7r
555-230-126
Issue 4
June 1999
Maintenance Object Repair Procedures
9-1854UDS1-BD (UDS1 Interface Circuit Pack)
9
transmitting the Yellow alarm and places the trunks or ports 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 board into a loopback 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 loopback mode. PLB Alarm is activated when a network
protocol activate bit pattern arrives over the 4Kbps ESF data link on the DS1 line.
PLB is deactivated when a network protocol deactivate bit pattern arrives over
the 4Kbps 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
