| 摘要 |
FIELD: radio engineering, communication.SUBSTANCE: invention relates to a broadcast encryption method. The technical result is achieved through a method of controlling decoders of at least one group of decoders, having access to audiovisual data, wherein the method comprises the following steps: at a step when the decoder should become a member of a group: obtaining and storing keys relating to a certain position in the group according to the broadcast encryption scheme; obtaining and storing current group access data containing at least the current group access key which is common for said group at the step of accessing the audiovisual data: using the current group access data for direct or indirect access to audiovisual data, at the step of updating the current group access key: transmitting a first group message containing at least the next group access data containing at least the next group access key encrypted such that only uncancelled decoders can gain access thereto, wherein said group message is further encrypted by the current group access key (CGK); updating the current group access key using the next group access key.EFFECT: high efficiency of controlling access to broadcast content for a large number of subscribers by controlling access only based on keys.5 cl, 4 dwg |
