Patent ID: 10515021

Abstract:
According to a first aspect of the present disclosure, there is provided an information storage device including a storage unit that stores encrypted content, usage control information of the encrypted content, and a revocation list in which revocation information of a content reproduction device is recorded, and a data processing unit that determines whether content reproduction of an information processing device which performs decoding of the encrypted content is permitted. The data processing unit acquires an entry identifier which is designation information for a registration entry of the revocation list recorded in the usage control information, executes an identifier registration determination process for determining whether an identifier of the information processing device which performs decoding of the encrypted content is registered in the entry of the revocation list identified according to the acquired entry identifier, and determines whether a subkey which is a generation key for a title key applied to the decoding of the encrypted content is to be provided to the information processing device based on a result of the identifier registration determination process.