What Is HLS Streaming and When Should You Use It (2024)

What is HTTP live streaming (HLS)?

HTTP live streaming (HLS) is one of the most widely used video streaming protocols. Although it is called HTTP “live” streaming, it is used for both on-demand streaming and live streaming. HLS breaks down video files into smaller downloadable HTTP files and delivers them using the HTTP protocol. Client devices load these HTTP files and then play them back as video.

One advantage of HLS is that all Internet-connected devices support HTTP, making it simpler to implement than streaming protocols that require the use of specialized servers. Another advantage is that an HLS stream can increase or decrease video quality depending on network conditions without interrupting playback. This is why video quality may get better or worse in the middle of a video as a user is watching it. This feature is known as “adaptive bitrate video delivery” or “adaptive bitrate streaming,” and without it, slow network conditions can stop a video from playing altogether.

HLS was developed by Apple for use on Apple products, but it is now used across a wide range of devices.

What is streaming?

Streaming is a way of delivering visual and audio media to users over the Internet. It works by continually sending the media file to a user’s device a little bit at a time instead of all at once. The original media file is stored remotely, or, in the case of live streaming, created in real-time with a remote camera or microphone. This way, the video or audio can play without the user’s device downloading the entire file first.

What is HTTP?

HTTP is an application layer protocol for transferring information between devices connected to a network. Every website and application accessible by regular users runs on HTTP. Data transfer over HTTP is typically based on requests and responses. Almost all HTTP messages are either a request or a response to a request.

With streaming over HTTP, the standard request-response pattern does not apply. The connection between client and server remains open for the duration of the stream, and the server pushes video data to the client so that the client does not have to request every segment of video data.

What other protocols are commonly used for streaming?

There are a number of similar protocols to HLS, like MPEG-DASH and HDS, that also run over HTTP and offer adaptive bitrate streaming. Adobe Flash, which ran on RTMP or HDS, used to be the main technology used for video streaming; however, many browsers no longer support Flash. RTMP is still in use, although support for it is declining.

Does Cloudflare support HTTP live streaming?

Cloudflare supports HLS for both on-demand and live streaming. Cloudflare Stream integrates video storage, encoding, and a customizable player with the fast, secure, and reliable Cloudflare network, which spans 310 cities in over 120 countries. This enables users around the world to receive fast, high-quality HLS streams. Learn more about Cloudflare Stream.