Medias Mediatrix 1204, Reference Manual

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Detecting a Far End Disconnect Reference Manual (SIP Version)
Mediatrix 1204 189
Detecting a Far End Disconnect
This section applies only to FXO lines with the analog line type set to Loop Start . See “Analog Line Type” on
page 185 for more details.
Far End Disconnect refers to methods for detecting that a remote party has hung up. The far end disconnect
signal is not mandatory in Loop Start and this could create problems. The lack of a far end disconnect signal
in Loop Start lines is one of the main reasons why the Ground Start lines were created.
If the Far End Disconnect signal is not sent to or properly detected by the Mediatrix 1204, the connection will
not be released by the unit, thus freezing the FXO line in the off hook state.
How to Solve the Problem
If you experience far end disconnect problems, you can use the following solutions. Please note that these
solutions are presented in order of effectiveness.
Solution 1: Use a Ground Start Trunk
This is the solution recommended by Mediatrix.
Configure or ask your provider to provide you with a Ground Start trunk. Normally, it does not
cost more than a Loop Start line.
Configure the Mediatrix 1204 in Ground Start mode. See “Analog Line Type” on page 185 for
more details.
Solution 2: Activate Current Drop/Power Denial Mode
If you experience far end disconnect problems, you can activate the Current Drop/Power Denial Mode. Review
your manufacturer's documentation for further details.
On the SCN side, configure or ask your provider to configure the PBX/ACD/CO to produce a Current Drop as
part of the far end disconnect signal.
Most PBXs/ACDs/COs offer the possibility to introduce a Current Drop as part of the far end disconnect signal.
The Mediatrix 1204 will detect a Current Drop if this signal is maintained for at least 600 ms with an open circuit
or has a current drop lower than 0.4 mA.
Note:
The Mediatrix 1204 does not support the line reversal feature.