I was looking for functionality which allows to the owner of the conference to stop it. This is a little different from HANGUP function.
The idea is to disconnect all participants and revoke jicofo conference + reservation (REST DELETE).
What is the best way to achieve this? I saw that there is libjitsi-meet api that allows sending commands to participant's browser app. So i can send hangup command to all or kick. The question may be : how to send a custom command to jicofo which will destroy physically the conference and revokes at reservation service.