What is Low-Latency HLS?
- Apple Low-Latency HLS is an extension to the HTTP Live Streaming (HLS) protocol spec (RFC8216) to enable low latency video broadcast streaming
- It lowers HLS streaming latency from ~15-30sec to ~4-6sec, allowing composed media streams to reach audiences in close to real-time
- This is accomplished by reducing each video segment size, so players have the ability to pull multiple segments much earlier than with standard HLS
- The low-latency extension is backward compatible for players that do not support it; older players will ignore partial segments allowing them to play just the standard HLS video segments.
- LL-HLS is still a relatively new addition to the spec, but is supported by many standard players. Link to HLS players that support LL-HLS here.
How do I enable LL-HLS broadcasts?
- Low-Latency HLS is available as a live streaming broadcast option for composed broadcasting of a vonage video session. To enable session broadcast in low-latency HLS mode, see Low-latency HLS broadcasts.
Why choose LL-HLS for broadcast?
- Choose LL-HLS to favor low delay for composed live streaming broadcasts
- LL-HLS provides many of the same HLS features, including:
- Simplicity - most common form of live video streaming
- Distribution Scale - distributed by HTTP servers
- High quality - adaptive bitrate for players to choose quality level
- LL-HLS provides this faster with lower latency, less delay
Why avoid LL-HLS for broadcast?
- When looking to favor reliability over reduced latency, choose legacy HLS compatibility
- Some player versions may have compatibility issues as the low-latency standard is adopted
- DVR functionality is not compatible with LL-HLS
Where can I find a comparison between WebRTC and LL-HLS?
Please refer to this blog