Video Tech Deep-Dive: Live Low Latency Streaming Part 3 – Low-Latency HLS
August 10, 2020This blog post is the final piece of our Live Low-Latency Streaming series, where we […]
Latency gets introduced at various points in the end to end chain
The encoder needs to be able to ingest live streams as quickly as possible with the encoding configuration optimized to produce the right size of chunks and segments that can then be uploaded to the Origin Server for delivery.
The upload time depends on connection type at upload facility (wired, wireless).
The CDN technologies need to allow for chunk-based transfers and to adopt the right caching strategies to propagate chunks across the different delivery nodes in a time sensitive fashion.
The end user’s network conditions also influence overall latency i.e. if the user is on a wired or WiFi or cellular connection. It also depends on how close the user is to the CDN edge.
The player needs to optimize start behavior and balance buffering and playback rate to enable quick download and rendering to always be as close as possible to live time. Chunked CMAF streams and low latency-enabled players are key elements in reducing latency in online streaming.
Even with all the end to end processing and delivery system built up and launched, low latency streaming may still be challenge to operate at scale - think of a very popular event such as the World Cup or Super Bowl with a variety of devices and players receiving it on a variety of last mile and in-home and mobile networks. Balancing a robust, scalable online streaming platform with minimal re-buffering and stream interruptions against the time-sensitive behavior of low latency CMAF streaming can be challenging. The answer is a holistic view of the streaming experience and a feedback loop, provided by Bitmovin Analytics.
