HLS (HTTP Live Streaming) is Apple's segmented adaptive-streaming protocol, standardized as IETF RFC 8216. It breaks a stream into short segments listed in an M3U8 playlist (the manifest); the player downloads the playlist, then fetches segments over ordinary HTTP, switching between renditions as the network changes. Because it rides plain HTTP, it traverses firewalls and caches in any CDN with no special infrastructure.
HLS is effectively mandatory: it is the only protocol natively supported by Apple's Safari, iOS, and tvOS, so any platform that wants Apple devices must serve HLS. It is also widely supported elsewhere, which makes it the most universal delivery format.
Modern HLS uses fragmented-MP4/CMAF segments (rather than the legacy MPEG-TS), which lets the same segments serve DASH too, and supports Low-Latency HLS (LL-HLS) for live. Its DRM path is FairPlay with the cbcs encryption scheme.
The handbook · 7 volumes
Fora Soft Video Engineering Handbook
HLS is the segmented streaming protocol Apple devices require and most other platforms accept, so its playlists and segment rules shape almost every OTT stack. The seven volumes cover the video stack; for HLS start with Volume 2 on HLS, CMAF, and segment protocols, then Volume 1 on encoding, with ABR, players, and CDNs in Volume 3. Written by Nikolay Sapunov, CEO at Fora Soft.
Building HLS delivery that plays the same on iPhone, browsers, and TVs?
We will review your packaging and playlists and send an HLS plan with segment settings and a device test matrix. 250+ video products shipped since 2005.
