ISO IEC 23009-4:2013 pdf free

ISO IEC 23009-4:2013 pdf free.Information technology一Dynamic adaptive streaming over HTTP (DASH)
The content protection framework provided in this part of ISO/IEC 23009 is a framework for out-of-band derivation of parameters needed for successful decryption of media segments. The tools provided are MPD interfaces that allow derivation of key and initialization parameters, baseline encryption and key resolution methods, and, lastly, it provides extensibility points to accommodate different key resolution and encryption algorithms using the same interface.
Conceptually, the content protection framework provided in this part of the standard can be viewed as two entities, key system and encryption system. Key system derives keys associated with a segment given the information provided in the MPD, while the encryption system decrypts media segments given the information provided in the MPD and encryption keys provided by the key system.
The baseline mandatory system applies AES-CBC encryption to a complete segment and uses HTTP(S) for key transport. In this baseline system the DASH client will be able to recognize uniquely for each segment which key and initialization vector were used for their encryption. The client will then issue a GET request for the key, and will either issue a GET request for the initialization vector or derive it locally. After receiving key and initialization vector, the DASH client can successfully decrypt the media segment and pass it to the media engine. In this description, AES-CBC ful-segment encryption is the encryption system, and key retrieval using HTTP(S) is the key system.
As most DRM systems employ license-based systems to derive keys, license-based key systems are supported in this standard. In this case, a license is retrieved, and the key URIs are opaque key identifiers.
The license-based key system will resolve these ID’s into keys in an unspecified way, and pass the keys to an encryption system. The latter, having keys provided by the key system and the encryption information (e.g.algorithm specification and IV) provided by the MPD, decrypts the media segment.ISO IEC 23009-4 pdf download.