TURN is used for relaying data from source to target. TURN consumes bandwidh and it is expensive.
Ephemeral password comes to the rescue here.
Learn WebRTC in 200 Line of code:
You will need a lot of patience going through libraries that are present today simply because they have thousands of line of code. So I will highly encourage you all to refer the source code located here: github.com/amiteshawa/learn-rtc