Low Latency HLS 2: Judgment Day

Apple has revised its HLS specification for delivering streams with low glass-to-glass latency, addressing concerns about the original standard's implementation and adoption barriers. The latest revision removes the requirement for HTTP/2 PUSH delivery of parts of media segments and introduces a new prefetch behavior signaled by a new tag in the HLS playlist - EXT-X-PRELOAD-HINT. This change makes Apple's LL-HLS specification more closely interoperable with MPEG DASH-LL, improving cache efficiency at CDN edges and potentially resulting in cost savings. However, challenges remain regarding bandwidth estimation in a browser and widespread adoption of the revised standard.