Patent ID: 8205083
Filing Date: 2012-06-19
Classification: G06F,G11B

Abstract:
1. A system for providing program information comprising: a user terminal managed by a user, a recording medium capable of reading information therefrom and writing information thereto through a command issued by the user terminal, and a server connected to the user terminal via a network, the system providing program information from the server to the recording medium, wherein the recording medium has a first storage unit capable of writing program information thereto, and a first control unit capable of performing a first mutual authentication operation with the user terminal and executing a command to write program information to the first storage unit only if the first mutual authentication operation is successful, the first storage unit of the recording medium stores media identifier information specific to the recording medium, key management information resulting from encryption in a predetermined format of media key information capable of being generated based on the media identifier information, and media-specific key information resulting from decryption of the media key information with the media identifier information, the first control unit of the recording medium performs a mutual authentication operation with the user terminal based on the media-specific key information, the user terminal comprises a second storage unit storing device key information and secret key information for the server, and a second control unit performing the mutual authentication operation with the recording medium, the second control unit of the user terminal: the server comprises a third storage unit storing secret key information for the user terminal or public key information, and a third control unit performing the mutual authentication operation with the recording medium, the third storage unit of the server stores program key information, program-key-encrypted program information resulting from encryption of the program information with the program key information, and correlation information correlating the media identifier information with different user key information for each user, the third control unit of the server generates, based on the correlation information, user-key-encrypted program key information resulting from encryption of the program key information with user key information corresponding to the media identifier information of the recording medium if a second mutual authentication operation with the user terminal is successful, and transmits the user-key-encrypted program key information and the program-key-encrypted program information to the user terminal, the user terminal performs the second mutual authentication operation with the server, obtains program information transmitted from the server if the second mutual authentication operation is successful, and issues a command to write the program information to the first storage unit of the recording medium, the third control unit of the server performs the mutual authentication operation with the user terminal based on the secret key information or public key information, the second control unit of the user terminal: the first storage unit of the recording medium stores in advance information resulting from encryption of the user key information with the media-specific key information, and the program-key-encrypted program information and the user-key-encrypted program key information received from the user terminal, the first control unit of the recording medium: