What's New in HTTP Live Streaming (HLS) 2nd Edition version 17 (2025): Content Steering Updates

The latest draft of the HTTP Live Streaming (HLS) 2nd Edition, draft-pantos-hls-rfc8216bis-17, introduces key refinements, particularly in the area of content steering. While the overall structure of the protocol remains consistent, these updates enhance HLS’s ability to dynamically direct clients to different content sources, improving scalability, resilience, and delivery efficiency.

Understanding Content Steering in HLS

Content steering is a mechanism that allows content providers to redirect clients to alternative playlists in real time based on network conditions, server load, and regional availability. This capability is especially crucial for large-scale streaming services that need to optimize content distribution dynamically.

Introduced in earlier versions, content steering is managed through the EXT-X-CONTENT-STEERING tag, which points to a JSON-based steering manifest. This manifest provides clients with updated URIs for alternative playlists, allowing seamless switching between different content endpoints without requiring a full manifest reload.

Key Enhancements in Content Steering

The draft-pantos-hls-rfc8216bis-17 document introduces refinements that improve the functionality of content steering:

Better Control Over Alternative Playlists

The JSON steering document now provides more structured and dynamic redirection options.
Content providers can specify fallback playlists for scenarios where a primary playlist becomes unavailable.

More Granular Client Steering

The updated mechanism allows for fine-tuned client routing, taking into account CDN load balancing, user location, and performance metrics.
This means that streams can be optimized based on network conditions in real time, reducing buffering and improving QoE (Quality of Experience).

Improved Failover Mechanism

If a client encounters an issue with its current stream, the steering manifest provides a list of backup sources, ensuring minimal service interruption.
This is particularly useful in cases where a server outage or congestion occurs, allowing seamless transitions to alternative streams.

Extended Interoperability

The JSON structure in the steering manifest is now more flexible, making it easier to integrate with various CDN strategies.
This aligns with the increasing trend of multi-CDN strategies used by large streaming platforms to optimize performance and cost.

How This Affects Streaming Workflows

For broadcasters and streaming service providers, these updates bring several advantages:

More control over traffic routing, reducing reliance on a single CDN or network provider.
Better resilience and failover handling, ensuring uninterrupted playback even during outages.
Optimized delivery paths, leading to improved viewer experience and lower latency.

Conclusion

While the HLS 2nd Edition draft does not introduce major overhauls to the protocol, its refinements in content steering provide valuable enhancements for modern streaming workflows. By offering more precise control over content distribution, these updates make HLS even more adaptable to large-scale, multi-CDN deployments.

As the draft moves toward finalization, streaming service providers should start evaluating these changes and consider implementing improved content steering strategies in their HLS-based platforms.

For more details, check out the full draft-pantos-hls-rfc8216bis-17 specification.

Article written by
Sylvain Corvaisier