Quick Eagle Networks DL3800E - Manual (Page 121)

Diagnostics 6-3
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.
T
ROUBLESHOOTING 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 built-in
diagnostic features of the DL3800E unit aid you in quickly identifying and
isolating faults.
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