It requires JavaScript on the client browsers side as it performs its work in client-server communication with the server side module in Joomla.
 
As overview Web-Call-Back allows:
 
* To enter any international phone number on the frontend

* Initiation of the call-back, either by internal extension first or outbound call with transfer to internal extension

* Fully customizeable messages for phone number form and status messages of the module

* Date & Time rules to be defined to show the module only during office hours or any specified period of times

* Show messages or hide the module when the internal extension or the PBX system is offline and the call back is unable to get performed.

* Output of debug information on communication with the Asterisk PBX.

Prerequisite for this module to perform its functions is a Asterisk PBX system for call initiation and transfer. This module requires knowledge and ability to configure a Asterisk PBX system, without these individual prerequisites this module will become difficult to startup. Support for the module is limited to the module itself, any issue that is dealing with Asterisk will be the users self responsibility.

Download:  Click Here 

Source: Joomla Feed