millisami said almost 2 years ago on Video Chat with WebRTC :
Hi, thanks for the video.
I could run this app with rails 7 and few modifications in import in video_chat_controoler.js locally without valid TURN server creds. Thought this was only in local.
Then I deployed the app on Render at https://drkiq.onrender.com/rooms and here also it works without valid TURN serve credential? 
Hows that possible just with Redis/ActionCable/Stimulus? 
Whats the exact role of TURN server here since its running without it?