Paradyne 7924 - Manual (Page 39)

Testing
7-3 7924-A2-GB20-30 October 1997
Remote Loopbacks
H
When a remote loopback is enabled, the red Loop Bk LED on the front panel
of the remote-end unit (CO or CP) lights up and remains lit until the loopback
is disabled. The loopback LED on the initiating unit does not light.
H A message appears on the remote-end unit reporting that it has been put into
loopback.
H
The data flow is indicated by the bold thick arrows in Figures 7-3 and 7-4 .
H When the CO initiates a remote loopback, an Alarm Indication Signal (AIS) is
received at the CP end (only if the CP end is G.703-compatible). (AIS is not
received at V.35-compatible CP units.)
Terminal 97-15515-01
CO CP
E1 HDSL
7900 7900
Diagnostic
Equipment
E1 HDSL
7900 7900
Diagnostic
Equipment
Loop Bk
LED lights
AIS
AIS = Alarm Indication Signal
Figure 7-3. Remote Loopback, Initiated at the CO Unit
Terminal 97-15517-01
CO CP
E1 HDSL
7900 7900
E1 HDSL
7900 7900
Diagnostic
Equipment
Diagnostic
Equipment
Loop Bk
LED lights
Figure 7-4. Remote Loopback, Initiated at the CP Unit