Testing

7-6 7610-A2-GB20-10
November 1997

Table 7-1. Test Status Messages (2 of 2)

Test Status Message Meaning

Network-init. DSU LB
Active A DSU Loopback initiated by the network is currently active.
If the network service is 56 kbps, the network loopback is
non-latching. A non-latching loopback ends when the
network activation codes stop.
If the network service is 64 kbps CC, the network loopback
is latching. This condition can only occur when the Network
Interface option Network-initiated DSU Loopback (64K CC)
is enabled. Refer to Network Interface Options, Table A-2.
No Test Active Status message, indicating no local, remote, or network test in
progress.
Sending 511 on
Network A 511 test pattern is being sent over the network interface.
Sending 511 on Port A 511 test pattern is being sent over the DTE port.
V.54-initiated DSU LB
Active A DSU loopback is active that was initiated by the detection of
a V.54 sequence originated by the remote unit. This condition
can only occur when V.54 Initiated DSU Loopback is enabled.
Refer to Network Interface Options, Table A-2.
Loopbacks

Loopbacks can be started from a variety of points in the network. Refer to

Table 7-2 for further information.

Table 7-2. Loopbacks (1 of 2)

Loopback Type Initiated By Notes

Bilateral Loopback ATI
NMS
Remote unit sending
V.54 sequence
When enabled, running a DSU loopback
also automatically starts a local
loopback. Refer to Data Port Options,
Table A-3, to enable.
CSU Loopback ATI (Network tests)
NMS
DDS Network, by
loop current reversal
When initiated by the network, CSU
Loopback cannot be disabled by the
user. When IMC is enabled, the
aggregate data is looped back to the
network.
DSU Loopback
(Digital) ATI
NMS
When IMC is enabled, only user data is
looped back to the network. Refer to
Data Port Options, Table A-3.
Local Loopback ATI
DTE via CT141
NMS
Control via CT141 can be disabled.
Refer to Data Port Options, Table A-3.