SCRAMBLE KEY MANAGEMENT UNIT, SCRAMBLE KEY MANAGEMENT INFORMATION TRANSMITTING UNIT, METHOD FOR SCRAMBLE KEY OUTPUT MANAGEMENT, SCRAMBLE KEY MANAGEMENT PROGRAM, LICENSE INFORMATION MANAGEMENT UNIT, LICENSE MANAGEMENT INFORMATION TRANSMITTING UNIT, METHOD FOR LICENSE INFORMATION OUTPUT MANAGEMENT, AND LICENSE INFORMATION MANAGEMENT PROGRAM

• US 20100088515A1
• Filed: 04/20/2007
• Published: 04/08/2010
• Est. Priority Date: 04/20/2007
• Status: Active Grant

• Current Assignee: Nippon Hoso Kyokai
• Original Assignee: Nippon Hoso Kyokai
• Inventors: Fujitsu, Satoshi, Sunasaki, Syunji, Nishimoto, Yusei
• Granted Patent: US 8,509,444 B2
• Time in Patent Office: Days
• US Class Current: 713/168
• CPC Class Codes: H04N 21/42623 involving specific decryption arrangements
• CPC Class Codes: H04N 21/43853 involving multiplex stream decryption arrangements using cryptography for the use of broadcast information or broadcast-related information H04H60/23
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

A low cost scramble key management apparatus which enables to manage a scramble key based on individual contract information and to ensure security in narrow band broadcasting. The scramble key management apparatus 7 includes an ECM decoding unit 75 for decoding an ECM in which a scramble key and individual contract information are encrypted. The individual contract information includes contract information indicating contract statuses of a plurality of content receivers 3, 3, . . . which is arranged based on receiver IDs for identifying each of the content receivers 3. The scramble key management apparatus 7 includes a contract information obtaining unit 76b for obtaining the contract information of the content receiver 3 associated with the receiver ID from the individual contract information and a contract status determining unit 76c for determining the contract status and outputting the scramble key to a content decoder 5 if the contract status is under contract.

Claims

1. A scramble key management apparatus which manages an output of a scramble key for decoding an encrypted content to a content decoder which receives and decodes the encrypted content, comprising:

a scramble key management information decoding unit for decoding scramble key management information in which the scramble key and individual authorization information are encrypted, the individual authorization information arranging authorization information indicating a presence or absence of authorization for each of a plurality of the content decoders to decode the encrypted content based on decoder IDs for identifying each of the content decoders;

an authorization information obtaining unit for obtaining the authorization information for the content decoder of an output target from the individual authorization information decoded by the scramble key management information decoding unit based on the decoder ID of the content decoder of the output target; and

an authorization status determining unit which determines whether or not the content decoder is authorized to decode the encrypted content based on the authorization information obtained by the authorization information obtaining unit, and outputs the scramble key to the content decoder of the output target if the content decoder is authorized to decode the encrypted content.

2. The scramble key management apparatus according to claim 1, wherein a plurality of content decoders which are transmission targets of the encrypted content is classified into a plurality of groups in advance, the authorization information of a plurality of the content decoders included in one of the plurality of groups is arranged in the individual authorization information, a group ID for identifying the one of the plurality of groups is included in the individual authorization information, and wherein

the authorization information obtaining unit obtains the authorization information based on the group ID and the decoder ID.

3. A scramble key management information transmitting apparatus which transmits to the scramble key management apparatus according to claim 1 scramble key management information in which a scramble key for decoding an encrypted content and individual authorization information are encrypted, the individual authorization information including authorization information indicating a presence or absence of authorization to decode the encrypted content for each of a plurality of content decoders which receives and decodes the encrypted content, comprising:

an individual authorization information generation unit for generating individual authorization information in which the authorization information for a plurality of the content decoders which is input from outside is arranged based on a decoder ID which identifies the content decoder, and

a scramble key management information generation unit for encrypting the individual authorization information generated by the individual authorization information generation unit and the scramble key to generate the scramble key management information.

4. The scramble key management information transmitting apparatus according to claim 3, wherein the individual authorization information generation unit generates the individual authorization information including a bit string in which the authorization information, each piece of which is one bit, is arranged.

5. The scramble key management information transmitting apparatus according to claim 4, wherein the individual authorization information generation unit losslessly compresses the bit string.

6. A scramble key output management method for managing an output of a scramble key for decoding an encrypted content to a content decoder which decodes the encrypted content, the method comprising steps of:

a scramble key management information decoding step for decoding scramble key management information in which the scramble key and individual authorization information are encrypted, the individual authorization information arranging authorization information indicating a presence or absence of authorization for each of a plurality of the content decoders to decode the encrypted content based on a decoder ID for identifying the each of the plurality of the content decoders;

an authorization information obtaining step for obtaining the authorization information for the content decoder of an output target from the individual authorization information decoded by the scramble key management information decoding unit based on the decoder ID of the content decoder of the output target;

an authorization status determining step for determining whether or not the content decoder is authorized to decode the encrypted content based on the authorization information obtained by the authorization information obtaining unit; and

a key output step for outputting the scramble key to the content decoder of the output target if the content decoder is determined to be authorized to decode the encrypted content in the authorization status determining step.

7. A scramble key management program which causes a computer managing an output of a scramble key for decoding an encrypted content to a content decoder which receives and decodes the encrypted content to function as:

a scramble key management information decoding means for decoding scramble key management information in which the scramble key and individual authorization information are encrypted, the individual authorization information arranging authorization information indicating a presence or absence of authorization for each of a plurality of the content decoders to decode the encrypted content based on a decoder ID for identifying each of the content decoders;

an authorization information obtaining means for obtaining the authorization information for the content decoder of an output target from the individual authorization information decoded by the scramble key management information decoding unit based on the decoder ID of the content decoder of the output target; and

an authorization status determining means for determining whether or not the content decoder is authorized to decode the encrypted content based on the authorization information obtained by the authorization information obtaining unit and outputting the scramble key to the content decoder of the output target if the content decoder is authorized to decode the encrypted content.

8. A license information management apparatus for managing an output of license information for displaying a content to a content obtaining unit which receives and displays the content, comprising:

a license management information decoding unit for decoding license management information in which individual authorization information is encrypted, the individual authorization information arranging authorization information indicating a presence or absence of authorization for each of a plurality of the content obtaining units to display the content based on a receiver ID for identifying each of the content obtaining units;

an authorization information obtaining unit for obtaining the authorization information for the content obtaining unit of an output target from the individual authorization information decoded by the license management information decoding unit based on the receiver ID of the content obtaining unit of the output target; and

an authorization status determining unit which determines whether or not the content obtaining unit is authorized to display the content based on the authorization information obtained by the authorization information obtaining unit, and outputs the license information to the content obtaining unit of the output target if the content obtaining unit is authorized to display the content.

9. The license information management apparatus according to claim 8, wherein the content obtaining unit is a content decoder which decodes an encrypted content which is encrypted with a scramble key with the scramble key, and the license information is the scramble key.

10. License information management apparatus which manages an output of license information for displaying a content to a content obtaining unit which receives and displays the content, comprising:

a license management information decoding unit for decoding license management information in which individual authorization information is encrypted, the individual authorization information arranging authorization information indicating a presence or absence of authorization for each of a plurality of the content obtaining units to display the content based on a first receiver ID which identifies each of the content obtaining units;

an authorization information obtaining unit for obtaining the authorization information for the content obtaining unit of an output target from the individual authorization information decoded by the license management information decoding unit based on the first receiver ID of the content obtaining unit of the output target;

a lock control information obtaining unit for obtaining lock control information associated with a second receiver ID for controlling a lock status which is either a status where the output of the license information to the content obtaining unit is allowed or a status where the output of the license information to the content obtaining unit is prohibited, the second receiver ID identifying a larger number of the content obtaining units than the first receiver ID;

a lock control unit for controlling the lock status based on the lock control information; and

an authorization status determining unit for determining whether or not the content obtaining unit is authorized to display the content based on the authorization information obtained by the authorization information obtaining unit, and outputting the license information to the content obtaining unit of the output target if the content obtaining unit is authorized to display the content and the lock status is the status where the output of the license information is allowed.

11. The license information management apparatus according to claim 10, wherein a plurality of content obtaining units which are transmission targets of the content is classified into a plurality of groups in advance, the authorization information of a plurality of the content obtaining units included in one of the plurality of groups is arranged in the individual authorization information, a group ID for identifying the one of the plurality of groups is included in the individual authorization information, and wherein

the authorization information obtaining unit obtains the authorization information based on the group ID and the first receiver ID.

12. The license information management apparatus according to claim 10, further comprising a first receiver ID storage unit for storing the first receiver ID, wherein if the lock control information includes information for controlling the lock status to the status where the output of the license information is allowed the lock control information includes at least a first receiver ID and the license information management apparatus updates the first receiver ID stored in the first receiver ID storage unit to the first receiver ID included in the lock control information.

13. The license information management apparatus according to claim 11, further comprising a first receiver ID storage unit for storing the first receiver ID and the group ID, wherein if the lock control information includes information for controlling the lock status to the status where the output of the license information is allowed the lock control information includes at least a first receiver ID and a group ID, and the license information management apparatus updates the first receiver ID and the group ID stored in the first receiver ID storage unit to the first receiver ID and the group ID included in the lock control information, respectively.

14. The license information management apparatus according to claim 10, further comprising a lock determining unit for determining whether or not to change the lock status to the status where the output of the license information is prohibited based on predetermined date information and a present date, wherein the lock control unit controls the lock status based on the lock control information and a determination result of the lock determining unit.

15. The license information management apparatus according to claim 10, wherein the first receiver ID is assigned a different ID by each channel in which the content obtaining unit receives the content, the different ID being associated with a channel ID for identifying a channel, and wherein the lock control unit controls the lock status by the each channel.

16. The license information management apparatus according to claim 14, wherein the first receiver ID is assigned a different ID by each channel in which the content obtaining unit receives the content, the different ID being associated with a channel ID for identifying a channel, and wherein the lock determining unit determines whether or not to change the lock status to the status where the output of the scramble key is prohibited based on the predetermined date information associated with the channel and the present date, and wherein the lock control unit controls the lock status by the each channel based on the lock control information and a determination result of the lock determining unit.

17. The license information management apparatus according to claim 10, wherein the content obtaining unit is a content decoder for decoding an encrypted content which is encrypted with a scramble key with the scramble key, and the license information is the scramble key.

18. A license management information transmitting apparatus for transmitting to the license information management apparatus according to claim 10 license management information in which individual authorization information is encrypted, the individual authorization information including authorization information indicating a presence or absence of authorization for each of a plurality of the content decoders which receives and displays a content to display the content, comprising:

an individual authorization information generation unit for generating the individual authorization information in which authorization information input from outside for the plurality of the content obtaining units is arranged based on a first receiver ID for identifying each of the content obtaining units;

a license management information generation unit for encrypting the individual authorization information generated by the individual authorization information generation unit to generate license management information; and

a lock control information generation unit for generating lock control information which is associated with a second receiver ID and changes a lock status of the license information management apparatus, the second receiver ID identifying a larger number of the content obtaining units than the first receiver ID.

19. A license information output management method for managing an output of license information for displaying a content to a content obtaining unit for receiving and displaying the content, comprising steps of:

a license management information decoding step for decoding license management information in which individual authorization information is encrypted, the individual authorization information arranging authorization information indicating a presence or absence of authorization for each of a plurality of the content decoders which receives and displays a content to display the content based on a first receiver ID which identifies each of the content obtaining units;

an authorization information obtaining step for obtaining the authorization information for the content obtaining unit of an output target which is decoded in the license management information decoding step based on the first receiver ID of the content obtaining unit of the output target;

an authorization status determining step for determining whether or not the content obtaining unit is allowed to display the content based on the authorization information obtained in the authorization information obtaining step;

a lock control information obtaining step for obtaining lock control information associated with a second receiver ID for controlling a lock status which is either a status where the output of the license information to the content obtaining unit is allowed or a status where the output of the license information to the content obtaining unit is prohibited, the second receiver ID identifying a larger number of the content obtaining units than the first receiver ID;

a lock control process step for controlling the lock status based on the lock control information obtained in the lock control information; and

a license information output step for outputting the license information to the content obtaining unit of the output target if the content obtaining unit of the output target is determined to be allowed to display the content in the authorization status determining step and the lock status is the status where the output of the scramble key is allowed.

20. A license information management program for managing an output of license information for displaying a content to a content obtaining unit which receives and displays the content, the program causing a computer to function as:

a license management information decoding unit for decoding license management information in which individual authorization information is encrypted, the individual authorization information arranging authorization information indicating a presence or absence of authorization for each of a plurality of the content decoders which receives and displays a content to display the content based on a first receiver ID which identifies each of the content obtaining units;

an authorization information obtaining unit for obtaining the authorization information for the content obtaining unit of an output target which is decoded in the license management information decoding step based on the first receiver ID of the content obtaining unit of the output target;

a lock control information obtaining unit for obtaining lock control information associated with a second receiver ID for controlling a lock status which is either a status where the output of the license information to the content obtaining unit is allowed or a status where the output of the license information to the content obtaining unit is prohibited, the second receiver ID identifying a larger number of the content obtaining units than the first receiver ID;

a lock control unit for controlling the lock status based on the lock control information; and

an authorization status determining unit for determining whether or not the content obtaining unit is authorized to display the content based on the authorization information obtained by the authorization information obtaining unit and outputting the license information to the content obtaining unit of the output target if the content obtaining unit is authorized to display the content and the lock status is the status where the output of the license information is allowed.