Dynamic adaptive HTTP streaming (DASH) is a new concept for video streaming using consecutive downloads of short video segments. 3GPP has developed the basic DASH standard which is further extended by OIPF and MPEG. In all versions available to date, content protection is not properly enabled. Extensions are needed to enable important use cases like pay-per-view, license change in an ongoing video channel, and pay-per-maximum-quality.
In this publication, Frank Hartung, Sinan Kesici and Daniel Catrein have examined which extensions are needed, in order to use DASH for DRM protected content. This comprises required changes in the DASH standard, namely MPD metadata extensions, as well as changes in the used transport file formats, namely the inclusion of a ISO file format box carrying a segment key, and finally a suitable key and license structure applied to the underlying DASH concept. All those changes have been proposed and explained in the paper. With these changes and additions, which do not change the core idea of DASH, even more complex use cases like pay-per-view and pay-per-maximum-quality are possible. As a proof-of-concept, the authors have implemented the proposed changes and integrated them with a real DRM key and license management system. For the proof-of-concept, they have used Marlin DRM, but any other similar DRM would be equally usable.
READ THE PAPER HERE : http://www.hartung.fh-aachen.de/publications/ACM_MMSys2011_p277.pdf
One of the first standardized DRMs for DASH. Interesting announced upcoming support for SIlverlight & XBox...