Sangoma Technologies is a Canadian company that has always been sponsoring FreeSWITCH morally and financially. However, until 2009, the code contributions were sparse. In 2008, the ZapTel project was renamed to DAHDI due to some trademark issues. Around the same time, in 2009, Sangoma started heavily reworking some areas of OpenZap so it could better be used as an API outside of FreeSWITCH for other standalone applications. This rework changed the API completely and improved other core areas within OpenZap. The heavy changes along with the fact that the original ZapTel project was renamed led to the renaming of the OpenZap project. It was decided between Sangoma and the FreeSWITCH development team to rename OpenZap to FreeTDM.

The FreeTDM project is a software library. As a library it's independent from FreeSWITCH and can be used in projects outside FreeSWITCH's scope. The library provides a unified high level API for analog and TDM signaling and access to the input/output configuration...