asterisk

Asterisk is an open-source command line tool used for building communication applications such as VoIP (Voice over Internet Protocol) systems and PBX (Private Branch Exchange) systems. It was initially developed by Mark Spencer and released in 1999 as a way to create a flexible telephony platform. Asterisk can run on various operating systems including Linux, Unix, and Windows. It supports various communication protocols such as SIP (Session Initiation Protocol), H.323, and IAX (Inter-Asterisk eXchange), allowing it to work with different devices and services. The tool provides features like call routing, voicemail, interactive voice response (IVR), call recording, and conferencing. Asterisk uses a configuration file where users define their telephony settings, extensions, and dial plan rules. It can be extended and customized through the use of dial plan scripts written in the Asterisk Extension Language (AEL) or Asterisk Dialplan Language (ADL). The tool also supports scripting languages like Perl, Python, and Lua for advanced customizations. Asterisk has a vast community of developers and users who contribute to its development, provide support, and create add-ons and modules. It has become popular among businesses and organizations looking for a cost-effective and flexible communication system.