Nortel Communication Server 1000S Maintenance Manual page 203

2.0 Mb PRI automatic loop test
With ATLP command set to one and if all 30 channels are idle at midnight,
the system software disables the card and performs a self-test on all channels.
This causes a Yellow alarm to be generated to the far end. If any one of the
30 channels are busy at midnight, the software randomly disables one idle
channel, and checks it while the card is enabled.
With the ATLP command set to zero, only one channel is tested. The channel
tested is randomly selected by software; it cannot be specified.
Enter the following command in LD 60 to perform the automatic loop test as
part of midnight routines:
ATLP 1 or 0
Link diagnostic and remote loop back tests
The remote loopback and the link diagnostic test are performed manually on
a per-channel or per-loop (or card) basis.
Link diagnostic test
The link diagnostic test, also called the far-end loopback test, does not test the
system 2.0 Mb PRI. It puts the 2.0 Mb PRI in loopback mode so a remote
loopback test can be performed on equipment at the far end. Refer to
Figure 33 on
The 2.0 Mb PRI channel or loop (card) tested must be disabled.
2.0 Mb PRI maintenance
page 204.
ISDN Primary Rate Interface
Page 203 of 210
Maintenance