FreeSWITCH is a scalable open source cross-platform telephony platform designed to route and interconnect popular communication protocols using audio, video, text or any other form of media. It was created in 2006 to fill the void left by proprietary commercial solutions. FreeSWITCH also provides a stable telephony platform on which many applications can be developed using a wide range of free tools.

FreeSWITCH can perform full video transcoding and MCU functionality using its conferencing module. FreeSWITCH supports many advanced SIP features such as presence/BLF/SLA as well as TCP TLS and sRTP. It also can be used as a transparent proxy with and without media in the path to act as a SBC (session border controller) and proxy T.38 and other end to end protocols. FreeSWITCH supports both wide and narrow band codecs making it an ideal solution to bridge legacy devices to the future. The voice channels and the conference bridge module all can operate at 8, 12, 16, 24, 32 or 48 kilohertz in mono or stereo and can bridge channels of different rates.

FreeSWITCH can be used with UniMRCP server in order to utilize a big variety of speech recognition and synthesis engines either installed on-premise or available as service.


Telephony Platform



  • Cloud-based Engines
  • On-premise Engines