HLS stands for "HTTP Live Streaming". It is called this because the video is delivered over HTTP(S), the same protocol used for loading web pages and much more, which is a desirable option for video that is meant to be viewed in a web browser, since a browser already is very good at handling HTTP.
HLS differs from older video transport protocols, such as RTMP (which is still used for connecting encoders to streaming servers), RTSP (often used for network cameras), and others in that HTTP transports entire files, whereas the other protocols send a continuous stream of data. Video is a continuous stream of data though, so how does this work? To send data over HLS, the server recieves a video source, either from a VOD file on disk, or an RTMP connection from an encoder, and it splits this video stream into short chunks of a few seconds. A manifest (m3u8 file) is also generated that lists the chunks of video, and a player can load the manifest, get each of the chunks, and play them in order.
Although this may seem a bit more convoluted than sending a continuous stream from server to viewer (because it is), there are a number of key advantages. HTTP servers are very good at transfering files to a client, so by using the same technique to get the video data onto the client, we can take advantage of the development and effort made to make web pages load quickly and efficiently rather than needing to develop our own systems. Similarly for displaying the streams to the viewers, it's much easier to make a web page than an entire application, allowing us to take advantage of the capabilities of modern web browsers for drawing entire interfaces quite easily. The individual files can be cached on a CDN enabling better performance for the hosts (like ScaleEngine), which means savings that can be passed on to the client (which could be you!)
In reality, these technical advantages are probably of limited interest to everyone involved, the main concern is getting a good and reliable stream. The real reason for using HLS is because it has become the industry standard and is supported by almost any modern device and operating system. Browsers natively support HLS playback with nothing more than a "player", which is a few lines of HTML and JS you can generate in our control panel (player system documentation) Apps such as roku or other set-top boxes and smart tvs will overwhelmingly use HLS for video playback, all of which we can support with the same HLS feeds used for browsers and phones.
If you would like to see this in action, you can Try a demo of our services. You can test out our systems on our production CDN for a week with no charges.
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