DASH

Acronym:Dynamic Adaptive Streaming via HTTP

The Moving Picture Experts Group (MPEG) ratified a standard for Dynamic Adaptive Streaming over HTTP (DASH) in late 2011, partly as a way to rationalize the numerous HTTP-based adaptive bitrate (ABR) solutions offered by Adobe, Apple, Microsoft, Move Networks and others. DASH offers either an MPEG-2 Transport Stream (M2TS) approach favored by Apple or a fragmented MP4 (ISO Base Media File Format) favored by Adobe and Microsoft. DASH defines two formats. The first is the Media Presentation Description (MPD) is somewhat equivalent to the Apple HTTP Live Streaming (HLS) manifest file, and “provides sufficient information for a DASH client for adaptive streaming of the content by downloading the media segments from a HTTP server. The second specification is the segment format construct, which addresses the “entity body of the request response when issuing a HTTP GET request or a partial HTTP GET.”