7.5.11 CallBack

What Is CallBack?

CallBack is a function used for external PBX extensions. With the CallBack you can easily reduce costs of external extensions. The extension with the CallBack enabled only alerts the PBX or sends an SMS in the appropriate form and the PBX calls back to this extension. After answering the call, the external extension can dial through the PBX as in the case of a direct call. So you do not need an expensive fixed payment tariff for all external extensions but only for your PBX SIM cards. This function is subject to licence.

CallBack Setting

Find the CallBack configuration menu in the Routing – Routing objects menu. The menu is divided into two parts. The left side is used for management and the right side for configuring the selected object. The context menu on the left consists of the following options:

  • Add – add a new object for CallBack.
  • Delete – delete a selected object.
  • Rename – rename a selected object.
  • Default – delete all current objects of this menu and create two default CallBack objects – one for calls and one for SMS messages.
  • Update – add the default CallBack objects preserving the current ones. If default objects have already been created, their parameters are set to default values.

On the right-hand side of the menu you can find the following parameters:

 

Ring CallBack

  • Name – display the name of the selected object.
  • CallBack delay [s] – define the delay between the CallBack recognition and execution.
  • Ring destination – this destination is used in the case of successful CallBack immediately after call answering by the external extension.
  • Ring detection time [s] – define the ringing time for incoming calls from a extension with the CallBack. If this timeout expires (the calling user does not hang up), the call is routed to Destination after timeout and behaves as a normal call and the CallBack function is not used.
  • Destination after timeout – this destination is used after the Ring detection timeout for another call routing. In the case of SMS CallBack, this destination is not used.

Figure: View of CallBack Configuration Menu for Calls

SMS CallBack

  • Name – display the name of the selected object.
  • CallBack delay [s] – set the delay between receving of the CallBack requesting SMS and request execution.
  • Delay in SMS content – omit the delay in the SMS to be sent.
  • Alerting destination – use the destination for routing the calls specified in the SMS.

SMS format

An incoming SMS for the CallBack function has to be routed to the text router for CallBack object routing. The SMS text depends on the Delay in SMS content setting: if Yes is selected, the SMS to the CallBack function will be as follows:

  • Called number, Delay, Calling number

 If the  Delay in SMS content  is set to No , the SMS message will be:

  • Called number, Calling number
  • Called number – this parameter is mandatory. Calls are routed according to the Alerting destination settings.
  • Delay – this parameter is optional and has the same function as CallBack delay, yet a higher priority.
  • Calling number – this parameter is optional and identifies the calling party if necessary. If absent, the SMS sender is used as the calling party.

Figure: View of CallBack Configuration Menu for SMS

 

Example 1 – Initiated by call

The external extension with an enabled and licensed CallBack function dials a PBX SIM card number. The call is routed to the CallBack object. When hearing the alert tone, the calling user can wait for the end of the Ring detection timeout. In that case, the CallBack function is not activated and the call is automatically routed according to the Destination after timeout. When the calling user hangs up before the timeout expiry, the CallBack and CallBack delay are activated. After the CallBack delay expiry, a CallBack to the external extension is established. The external extension user answers the call and can go on dialling through the PBX according to the Alerting destination.

 

Example 2 – Initiated by SMS

The external extension with an enabled and licensed CallBack function sends an SMS message to a PBX SIM card. The SMS is routed to the CallBack object. The SMS text may be 800123456,30, for example. The PBX waits for a timeout (30s) and after that establishes a CallBack to the external extension. The external extension user answers the call and the PBX sets up a call to the called party 800123456 using the Alerting destination parameter.