Ask HN: Modern live streaming solutions for the web

Now that Blab has shut down, it renewed my interest in live streaming. Last time I approached the problem, the consensus was to use Flash for RTMP. After Chrome has renounced support for it, I would like to know what other solutions are currently available. I know WebRTC is one, but peer-to-peer streaming has its limitations. How did services like Blab do it? Is it through Websockets?