Testing

7-9

7112-A2-GB20-20 March 1998
Data Channel Loopback
Data Channel Loopback (DCLB) loops the data from all network DS0 channels
assigned to the port back to the network. This loopback is located as closely as
possible to the User Data Port (DTE) interface.
"Procedure
To run a data channel loopback:
1. Position the cursor at the Start command next to Data Channel Loopback on
the Sync Data Port Tests screen and press Enter.
The Start command is changed to Stop.
2. If you want to manually stop the test, verify that the cursor is positioned at the
Stop command and press enter.
97-15695

CSU DSU

Network
Interface DCLB
DTE
Port 1
ALL 1s
Data Channel Loopback cannot be started when any of the following tests are
active:
HLine, Payload, or Repeater Loopback on the network interface
HDTE Payload loopback on the data port.