What this means is that I actually need to watch a different encoding of the video if I'm on my cellular data connection than if I'm using my home internet. If I'm watching a video on my phone on a not-very-great cellular data connection, I have a lot less bandwidth available than if I were watching the same video at home where my Internet connection is (usually) very fast. This is generally important for video delivery at scale, and it's especially important for live streams. There are quite a few nice things about HLS, but two advantages in particular over RTMP.įirst, HLS supports multiple bitrates and allows viewing clients to switch between multiple bitrates dynamically. Twitch uses a much newer standard, HLS, to deliver video to the millions and millions of people who watch live streams every day.

On the other hand, if you're watching a stream on Twitch, you're not watching that original RTMP stream. If you are a Twitch streamer, for example, you're almost certainly using RTMP to send video from your gaming machine/music studio/vibe lab to Twitch's cloud infrastructure. But because RTMP has been around so long, it's widely supported as a way to send live video from one computer system to another. That's pretty ancient technology in Internet video terms. RTMP is 20 years old, and was originally developed by Macromedia for the Flash server and player. From RTMP to HLS: Two decades of progress in live streaming HLS and WebRTC are nice examples of two (good) approaches to solving a problem (video streaming) that optimize for very different aspects of that problem. Our computers and phones and networks continue to get faster, people keep thinking up new things to do with faster computers and networks, and better and better technical building blocks are created to support these new things we're all doing.īut also, delivering video at scale is challenging, and engineering trade-offs abound. Well, partly these standards evolved over time, and are still evolving. WebRTC was designed to support interactive use cases like video calls, and is the underlying technology in applications like Google Meet, Microsoft Teams video, and Discord video.HLS is how platforms like Twitch deliver live streams to large audiences.

RTMP is widely used to send video into a live session, but is rarely used for viewing video streams.These days, when people talk about 'live streaming,' they might be talking about three quite different underlying technologies.

Real time video player