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 p orts back into the service
state before the Blue alarm occ urs.
Line Loopback Alarm
The Line Loopback (LLB) is used by the remote DS1 endpoint to put t he ICSU or
DS1 board into a loopbac k mode. When the ICSU or DS1 board is in the LLB
mode, the arriving bit p attern is regenerated and sent back. Line Loop back (LLB)
Alarm is activated when the in-b and activate LLB b it pattern has been arriving
continuously for 5 seconds on the DS1 line. LLB is deactivated when the in-b and
deactivate LLB bit p attern has been arriving c ontinuously for 5 seconds on t he
DS1 line.
Since LLB is a maintenance cond ition rendering all DS0 channels unava ilable for
signaling or bearer traffic , maintenance software treats this the same as a Blue
Alarm.
Payload Loopback Alarm
The Payload Loopback (PLB) is used b y the remote DS1 endpoint to put the
switch DS1 into a loopback mode. PLB Alarm is activated when a network
protocol activate b it pattern arrives over the 4Kbp s ESF data link on the DS1 line.
PLB is deactivated when a network p rotocol deactivate b it pattern arrives over
the 4Kbps ESF data link on the DS1 line.
Since PLB is a maintenance condition render ing all DS0 channels unavailable for
signaling or bearer traffic , maintenance software treats this the same as a Blue
Alarm