Testing; Detecting A Problem; Understanding Loopbacks - Paradyne HOTWIRE 7900 User Manual

Testing

Detecting a Problem

Understanding Loopbacks

7900-A2-GB20-00
The MTU-M can detect and report problem conditions and allow you to perform
diagnostic testing of the xTU-C/R pair. The MTU-M offers a number of indicators
to alert you to possible problems, as described in Chapter 7,
Once you have detected a problem, you can further isolate the problem to your
local equipment, remote equipment, or the copper lines.
A loopback is a diagnostic function that enables a technician to isolate equipment
on the DSL circuit to determine where on the circuit trouble may be occurring.
Loopback takes the system offline. Data received from T1 or E1 application
equipment is looped back as shown in the following sections.
Local and remote refer to the point at which the data is looped back. In a local
loopback, the data is reflected back by the local unit (the unit that initiated the
loopback). In a remote loopback, the data is passed on to the remote (far-end)
unit and then reflected back.
Local and Remote loopback tests may be initiated from either the CO or CP end
of the loop, however, the MTU-M only communicates with the the local xTU-C
(CO).
March 1998
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MTU-M Front Panel.
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