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call timer to disconnect a FXO port during a call

Is there a command that will disconnect a call on an FXO port say after a few minutes to limit the caller for a specified amout of time for his call..


New Member

Re: call timer to disconnect a FXO port during a call



In this section, you are presented with the information to configure the features described in this document.

Note: To find additional information on the commands used in this document, use the Command Lookup Tool ( registered customers only) .

Configure PLAR OPX and Hookflash Relay

Use this procedure to configure private line, automatic ringdown (PLAR) Off-Premises extension (OPX), and hookflash relay.

Configure the FXO port on the MainSite router as connection plar-opx.

The OPX mode allows remote users on FXS ports to appear to a central PBX as a directly connected extension. When the FXO port detects a ring signal from the PBX, the router sends a VoIP call setup to the remote FXS port but it does not take the FXO port off-hook. As a result, the PBX only sees the call answer signal when the RemoteSide router FXS port is picked up. After the PBX reaches the no answer timeout (call rings out), then it can end the call, transfer the call to voice mail, or ring another extension/ring group. Without OPX mode, the FXO port immediately goes off-hook after it senses the ringing and the PBX is then unable to perform a call forward, no answer, or roll over to voice mail.

The RemoteSite router must be configured to sense and then pass the hookflash signal on the FXS port.

Since the hookflash is a momentary break in the loop current on the FXS port and cannot be sent as an audio signal, the router passes the hookflash signal via dual tone multifrequency (DTMF) relay as the '!' character. The router with the FXO port then sends a short loop break which the external device sees as a hookflash. To properly pass the hookflash signal, the VoIP dial peers need to be configured for dtmf-relay h245-signal.

The physical port timers have to be adjusted to suit the characteristics of the handset on the FXS port and the duration of the hookflash loop break out of the FXO port as shown here:

The FXS voice port (RemoteSite router) uses the timing hookflash-in msec command where msec is the maximum value of a loop break (in milliseconds) from the telephone handset that is interpreted as a hookflash. A loop break greater than the configured value is regarded as a disconnect and the call is dropped. Any interval under this value causes the router to send the '!' character via the H.245-signal DTMF relay.

The FXO voice port (MainSite router) uses the timing hookflash-out msec command where msec is the duration of the outgoing loop break in milliseconds. When the router receives an H.245-signal DTMF relay signal, the FXO port generates a loop break for the configured interval.



voice-port x/y

timing hookflash-out 500

Under Voip Dial-peer


dial-peer voice xxx voip

incoming called-number .

destination-pattern xx.

session target ipv4:x.x.x.x

dtmf-relay h245-signal



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