Before setting up Voice Channel, ensure you have the following prerequisites:
Asterisk 16.19.0 or higher (We used FreePBX 16.0.10.40 with Asterisk 18.6.0)
Valid SSL certificate (valid domain)
A Rocket.Chat workspace on version 5.0.0 or higher
Key terms
A private branch exchange (PBX) is a telephone system within an enterprise that switches calls between users on local lines while enabling all users to share a certain number of external phone lines.
Asterisk is an open-source software implementation of a PBX.
FreePBX is a web-based open-source GUI (graphical user interface) that controls and manages Asterisk (PBX).
Refer to Voice Channel Technical Specification to gain more understanding on the architecture of voice channel in Rocket.Chat. In the next guide, we'll delve deeper on how to configure voice channel in your workspace as an administrator.