The present document is designed to be used in conjunction with EN 300 468 [2] and TR 101 211 [22]. The DVB System provides a means of delivering MPEG-2 Transport Streams (TS) via a variety of transmission media. These TSs have traditionally been oriented to containing MPEG-2 Video and Audio. Data broadcasting is seen as an important extension of the MPEG-2 based DVB transmission standards. Examples for data broadcasting are the download of software over satellite, cable or terrestrial links, the delivery of Internet services over broadcast channels (IP tunnelling), interactive TV, etc. Four different application areas with different requirements for the da