BROADCAST TRANSMISSION-RECEPTION METHOD, BROADCAST TRANSMITTER, BROADCAST RECEIVER AND BROADCAST TRANSMISSION-RECEPTION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a broadcast transmission-reception method, a broadcast transmitter, a broadcast receiver and a broadcast transmission-reception system by which common contents can be used among a plurality of the unit services while maintaining the security among a plurality of the different unit services. SOLUTION: In this broadcast transmission-reception method by which contents can be available for only contracted users by enciphering/transmitting contents and giving a key to decode the encipherment to the contracted users for the contents, each of one or more contents included in each unit service is locked respectively, keys for each unit service are locked in bulk and one key is given for every unit service, since it is inconvenient that respective keys are given separately.