The Jigasi daemon connects to our VoIP server and has its own extension. You can either call a VoIP extension from inside the Jitsi conference, or route an incoming call to a specific Jitsi conference.

This means that our existing Polycom-based conference room setups can be bridged with Jitsi Meet with no effort. Our work-from-home people can just dial the physical conference room from a Jitsi Meet conference.

https://github.com/jitsi/jigasi