6 
Payload Loopback and Line Loopback Tests
Use the PAYLOAD Loopback and LINE Loopback tests to verify the proper operation of the DL3800E unit and selected E1 networks.
Both tests loop the payload data received from the E1 network back to the network.
With the PAYLOAD Loopback, the DL3800E unit regenerates the data and inserts a new framing pattern before it loops back the data. This verifies the unit’s E1 framing and the E1 network.
With the LINE Loopback, the DL3800E unit does not do any additional processing of the data before it regenerates it and loops it back. This minimizes the involvement of the DL3800E unit during this test so that problems can be isolated to the network.
PAYLOAD and LINE Loopbacks remove the port from the DTE data bundle unless the port is configured to “Install/Test Only” mode.
Possible Sources of Problems
The PAYLOAD Loopback can test a problem whose source may be the
DL3800E.
The LINE Loopback can test a problem whose source may be the Telco E1 line, wiring between the Telco demarcation points, the DL3800E unit at one or both ends, or the cable between the E1 line reporting errors and the DL3800E.
The TEST LED on the DL3800E unit turns red during the tests, and the E1 port LED turns yellow.
TROUBLESHOOTING THE DL3800E
This section describes problems you may encounter on the DL3800E unit and suggests ways you can troubleshoot them.
The troubleshooting procedure is designed to isolate the faulty or malfunctioning item to the E1 network, the DTE equipment, the cable from the DTE to the DL3800E unit or the DL3800E unit itself. The
Using the front panel buttons and display, the ASCII terminal or SNMP workstation, you can run a series of loopback tests. Verification of the proper functioning of the DTE equipment and the DL3800E unit is
Diagnostics |
