Filter
Top Products
MG-DS1 (DS1 Interface Media Module)
Issue 1 June 2005 1611
Line Loopback Alarm
The Line Loopback (LLB) is used by the remote DS1 endpoint to put the DS1 board into a
loopback mode. When the DS1 board is in the LLB mode, the arriving bit pattern is regenerated
and sent back. The Line Loopback (LLB) Alarm activates when the in-band activate LLB bit
pattern arrives continuously for 5 seconds on the DS1 line. The LLB deactivates when the
in-band deactivate LLB bit pattern arrives 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. The PLB Alarm activates when a network protocol activate bit pattern arrives
over the 4Kbps ESF data link on the DS1 line. The PLB deactivates 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
Table 593: TEST #139 Blue Alarm Inquiry Test
Error
Code
Test
Result
Description/ Recommendation
ABRT Internal system error
1. Retry the command at 1-minute intervals for a maximum of 5 times.
1 of 4