Introduction The principles described in this Annex should facilitate the development of effective conditionalaccess systems for digital broadcasting that are convenient for both subscribers and service providers@ assuring reliable protection of information from unauthorized access. The principles apply generally to the delivery of digital television services@ sound services as well as multimedia and data broadcasting services. These principles apply to both Recommendation ITU-T H.220.0 transport stream packet and MMTP packet delivery to consumers over different media@ such as digital terrestrial@ digital cable@ digital satellite and IP (Internet Protocol) broadcasting.