Content distribution server and content playback control terminal

摘要

In the present invention, a content distribution server distributes a content key, encrypted content encrypted using the content key, and playback control information describing a playback mode restriction for a specific section of content, to a content playback terminal, and the content playback terminal refers to the playback control information, and decodes and plays back encrypted content in the case of a playback mode in which the specific section of content is not restricted. By this means, the playback mode of a specific section of content can be restricted based on playback control information.

主权项

1. A content playback control method, comprising:
storing in a memory, information describing:
license information including a content key and a usage condition;special sections subject to a restriction of a special playback of content, the special sections being received separately from the license information; anda playback mode permitted in each of the special sections,the usage condition specifying whether a playback is performed with respect to the special sections and the playback mode,the usage condition and at least one of the special sections and the playback mode correspond to identification information so that an issuer can set a plurality of the special sections or the playback mode using the identification information, and the identification information attached to the license information for encrypted content and playback control information; decoding encrypted content using the content key to generate decoded content, only when the usage condition is met; determining, when an instructed special playback of the decoded content is performed and the usage condition specifies the special sections of the decoded content described in the information stored in the memory, whether the special sections of the decoded content described in the information stored in the memory include a point at which the instructed special playback is performed; and controlling the instructed special playback for the decoded content, when the special sections include the point at which the instructed special playback is performed, and when the usage condition specifies that the playback is performed based on the playback mode described in the information stored in the memory, and a playback mode of the instructed special playback corresponds to one of the playback mode described in the information stored in the memory.