Hard real time udp communications is quite appealing. WebRTC and Object Real Time Communications (ORTC) claim to provide real time communications with udp. Does this mean "close enough to wall clock time to not notice" or are they designed with hard real time determinism requirements?
Are there any tests showing deterministic udp communications?
How real-time are these communication methods?
Definitely not "close enough to wall clock time to not notice"
100 ms latency at best, 300-800 ms in average, no guarantees and no mission-critical grade reliability. You should not use any IP-based technologies for for mission-critical applications. IP (internet protocol) was not designed for that.
Consumer-grade toy, nothing more. If it fails or freezes, you refresh your browser or come back in 10 minutes and try again. You would not use these technologies for military applications, remote control of medical machine conducting some procedure, and anything else that requires ultra-high reliability.
However, good enough for video conferencing and surveillance over web, where nobody dies if the application hangs 2% of times, and 500 ms latency is acceptable.
Try https://appr.tc/ for testing.