Information processing method, information processing apparatus and recording medium

• US 20020114466A1
• Filed: 02/08/2002
• Published: 08/22/2002
• Est. Priority Date: 02/09/2001
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Tanaka, Koichi, Ishiguro, Ryuji, Kawakami, Itaru, Kuroda, Yoshisuke
• Granted Patent: US 7,260,721 B2
• Time in Patent Office: Days
• US Class Current: 380/232
• CPC Class Codes: G06F 21/107 License processing; Key processing
• CPC Class Codes: G06F 21/1076 Revocation
• CPC Class Codes: G06F 2221/2135 Metering
• CPC Class Codes: G06F 2221/2137 Time limited access, e.g. to a computer or data
• CPC Class Codes: G06Q 20/3821 Electronic credentials

Abstract

A client receives encrypted content from content server. The header of the content includes license-identifying information for identifying a license required to utilize the content. The client requests a license server to transmit the license identified by the license-identifying information. When receiving the request for a license, the license server carries out a charging process before transmitting the license to the client. The client stores the license received from the license server. The stored license serves as a condition for encrypting and playing back the content. As a result, content can be distributed with a high degree of freedom and only an authorized user is capable of utilizing the content.

Claims

1. An information processing apparatus for allowing usage of content by requiring a license for using said content, said information processing apparatus comprising:

a content storage unit operable to store license-identification information for specifying said license for using said content, encrypted data of said content and key information required for decrypting said encrypted data of said content;

a license storage unit operable to store said license for using said content, including content-specifying information for specifying said content, the use of which is allowed by said license;

a judgment unit operable to determine whether said license for using said content has been stored in said license storage unit; and

a decryption unit operable to decrypt said encrypted data of said content if said license for using said content has been stored in said license storage unit.

2. An information processing apparatus according to claim 1, further comprising:

a transmitter operable to transmit a request for said license to a license server, said license request including said license-identification information; and

a receiver operable to receive said license transmitted by the license server,

wherein said received license is stored in said license storage unit.

3. An information processing apparatus according to claim 1, further comprising:

a reproducing unit operable to reproduce said data of said content decrypted by said decryption unit, wherein said data of said content is text data, image data, audio data, moving-picture data or combinations thereof.

4. An information processing apparatus according to claim 1, further comprising:

a device-node-key storage unit operable to store a device node key, wherein

said key information includes an EKB (Enabling Key Block); and

said decryption unit is operable to decrypt said EKB (Enabling Key Block) using said device node key to obtain a root key, and to decrypt said data of said content using said root key.

5. An information processing apparatus according to claim 4, wherein:

said key information further includes a content key encrypted using said root key;

said data of said content is encrypted using said content key; and

said decryption unit is operable to decrypt said encrypted data of said content using said root key.

6. An information processing apparatus according to claim 1, wherein said license further includes usage-condition information showing a condition for using said content, the use of which is allowed by said license.

7. An information processing apparatus according to claim 1, wherein said license further includes an electronic signature signed by using a secret key of a license server.

8. An information processing apparatus according to claim 2, further comprising:

a terminal-ID storage unit operable to store terminal-identification information identifying said information processing apparatus, wherein

said license request further includes said terminal-identification information;

said received license includes a terminal ID; and

said judgment unit compares said terminal ID in said received license with said terminal-identification information stored in said terminal-ID storage unit and determines that said received license is said license for using said content only if said terminal ID in said received license matches said terminal-identification information stored in said terminal-ID storage unit.

9. An information processing method for allowing a user to use content by requiring the user to have a license for using the content, the information processing method comprising:

storing license-identification information for specifying the license for using the content, encrypted data of the content and key information required for decrypting the encrypted data of the content;

storing the license for using the content in a license storage unit, the license including content-specifying information for specifying the content, the use of which is allowed by the license;

determining whether the license for using the content has been stored in the license storage unit; and

decrypting the encrypted data of the content if the license for using the content has been stored in the license storage unit.

10. A recording medium recorded with a program to be executed by a computer for carrying out processing to allow a user to use content by requiring the user to have a license for using the content, the program comprising:

storing license-identification information for specifying the license for using the content, encrypted data of the content and key information required for decrypting the encrypted data of the content;

storing the license for using the content in a license storage unit, the license including content-specifying information for specifying the content, the use of which is allowed by the license;

determining whether the license for using the content has been stored in the license storage unit; and

decrypting the encrypted data of the content if the license for using the content has been stored in the license storage unit.

11. A program according to claim 10, wherein the program or a portion of the program is encrypted.

12. A license server for issuing a license for allowing the use of content, said license server comprising:

a license storage unit operable to store said license, said license including content-specifying information for specifying said content, the use of which is allowed by said license, and terminal-identification information for identifying an information processing apparatus;

a receiver operable to receive a request for said license from said information processing apparatus, said license request including license-identification information for identifying said license;

an extraction unit operable to extract said license identified by said license-identification information from said license storage unit;

a processor operable to add said terminal-identification information to said extracted license;

a signature unit operable to put a signature on said extracted license including said terminal-identification information using a secret key of said license server; and

a transmitter operable to transmit said extracted license with said signature thereon to said information processing apparatus.

13. A method for issuing a license for allowing the use of content, the method comprising:

storing the license in a license storage unit, the license including content-specifying information for specifying the content, the use of which is allowed by the license, and terminal-identification information for identifying an information processing apparatus;

receiving a request for the license from the information processing apparatus, the license request including license-identification information for identifying the license;

extracting the license stored in the license storage unit and identified by the license-identification information;

adding the terminal-identification information to the extracted license;

putting a signature on the extracted license including the terminal-identification information using a secret key; and

transmitting the extracted license with the signature thereon to the information processing apparatus.

14. A recoding medium recorded with a program to be executed by a computer for carrying out processing to issue a license for allowing the use of content, the program comprising:

storing the license in a license storage unit, the license including content-specifying information for specifying the content, the use of which is allowed by the license, and terminal-identification information for identifying an information processing apparatus;

receiving a request for the license from the information processing apparatus, the license request including license-identification information for identifying the license;

extracting the license stored in the license storage unit and identified by the license-identification information;

adding the terminal-identification information to the extracted license;

putting a signature on the extracted license including the terminal-identification information using a secret key of a license server; and

transmitting the extracted license with the signature thereon to the information processing apparatus.