Local Loopback Tests; Starting A Line Loopback - Paradyne 3150 Operator's Manual

Local Loopback Tests

The Local Loopback tests enable you to conduct circuit
testing and fault isolation for the digital line. The
supported local loopback tests are:
Line Loopback (LLB)
Payload Loopback (PLB)
DTE Loopback (DLB)
Repeater Loopback (RLB)
The Line Loopback command can be activated and
deactivated in response to commands received over the
network interface. The Network Interface configuration
option NET LLB controls whether the CSU responds to
the commands transmitted on the network interface to
initiate LLBs (see Appendix C,
Local loopback tests can be aborted (Abort Command)
at any time.
No more than two local loopbacks can be active at any
one time. An additional restriction prohibits certain
loopbacks from running at the same time. Valid loopback
combinations listed in Table 4-8
Table 4-8
Valid Loopback Combinations
LLB PLB
LLB N/A NO
PLB NO N/A
DLB YES YES
RLB YES NO
3150-A2-GB21-80
Configuration Options).
are identified by YES.
DLB RLB
YES YES
YES NO
N/A NO
NO N/A
February 1998

Starting a Line Loopback

The Line Loopback command (LLB) loops the
received signal on the network interface (NI) back to the
network without change.
To perform a Line loopback,
1. From the top-level menu screen, select Test.
2. From the Test screen, select Lpbk.
Test:
Rlpbk Lpbk
F1
3. From the Loopback screen, select LLB.
Loopback:
Abort
F1
Test Started appears on Line 2. If a line loopback
is already in progress, the Already Active
message appears. If an invalid combination of
loopbacks is in progress, the error message Invld
Test Combo appears (see
loopback test combinations).
Maintenance
Ptrns
F3
F2
LLB PLB
F2 F3
Table 4-8 for valid
4-15