Digital data recording apparatus, digital data recording method, and computer-readable recording medium

• US 6,834,348 B1
• Filed: 07/22/1999
• Issued: 12/21/2004
• Est. Priority Date: 07/22/1998
• Status: Expired due to Term

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Tagawa, Kenji, Kozuka, Masayuki, Minami, Masataka
• Primary Examiner(s): Vu, Kim
• Assistant Examiner(s): Seal, James
• Application Number:
  US09/358,820
• Time in Patent Office: 1,979 Days
• Field of Search: 713/201, 713/193, 713/150, 380/277
• US Class Current: 713/193
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00094 involving measures which result in a restriction to authorised record carriers
• CPC Class Codes: G11B 20/00115 wherein the record carrier stores a unique medium identifier
• CPC Class Codes: G11B 20/00195 using a device identifier associated with the player or recorder, e.g. serial numbers of playback apparatuses or MAC addresses
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00224 wherein the key is obtained from a remote server
• CPC Class Codes: G11B 20/00246 wherein the key is obtained from a local device, e.g. device key initially stored by the player or by the recorder
• CPC Class Codes: G11B 20/00347 wherein the medium identifier is used as a key
• CPC Class Codes: G11B 20/00478 wherein contents are decrypted and re-encrypted with a different key when being copied from/to a record carrier
• CPC Class Codes: G11B 20/0071 involving a purchase action
• CPC Class Codes: G11B 20/00753 wherein the usage restriction limits the number of copies that can be made, e.g. CGMS, SCMS, or CCI flags
• CPC Class Codes: G11B 20/00876 wherein physical copy protection means are attached to the medium, e.g. holograms, sensors, or additional semiconductor circuitry

Abstract

A data transmit/receive unit receives encrypted digital data distributed through an electronic music distribution system and records the digital data on a primary recording medium. Digital data have been encrypted in different encryption systems according to the distributers, and include attribute information indicating the encryption systems. The encryption system of digital data that has been extracted by a data extraction unit is judged by a judging unit and decrypted by an appropriate decryption unit. An inherent information obtaining unit obtains the identification information of a secondary recording medium or a playback apparatus according to whether the secondary recording medium can be removable from the playback apparatus. An encryption system designation unit selects one out of a plurality of encryption units according to the obtained identification information. The selected encryption unit creates a encryption key according to the identification information and encrypts the digital data. A recording unit records the digital data on the secondary recording medium. An accounting unit charges according to accounting information in the attribute information.

Claims

1. A digital data recording apparatus for recording digital data on a recording medium, said apparatus comprising:

a communication unit operable to receive encrypted digital data via a digital network;

a decryption unit operable to decrypt the encrypted digital data received by said communication unit;

an encryption unit including a plurality of encryption sub-units operable to re-encrypt decrypted digital data in encryption systems having different security levels;

a recording unit operable to record digital data that has been re-encrypted by said encryption unit on the recording medium;

an accounting unit operable to conduct an accounting process via the digital network; and

a controller operable to control said decryption unit, said encryption unit and said accounting unit;

wherein said controller is operable to select and control one of said encryption sub-units from among said plurality of encryption sub-units to re-encrypt the digital data that has been decrypted by said decryption unit, to determine an accounting value according to said one of said encryption sub-units that has re-encrypted the decrypted digital data, and to control said accounting unit so that said accounting unit conducts the accounting process according to the determined accounting value.

2. The digital data recording apparatus according to claim 1, wherein:

the digital data recorded on the recording medium is reproduced by a playback apparatus;

said encryption unit includes

a first encryption sub-unit operable to re-encrypt digital data by using an encryption key that has been created according to identification information of the recording medium, and

a second encryption sub-unit operable to re-encrypt digital data by using an encryption key that has been created according to identification information of the playback apparatus; and

said controller is operable to determine whether the recording medium is removable from the playback apparatus, to control said first encryption sub-unit to re-encrypt the decrypted digital data when the recording medium is removable from the playback apparatus, and to control said second encryption sub-unit to re-encrypt the decrypted digital data when the recording medium is not removable from the playback apparatus.

3. The digital data recording apparatus according to claim 2, wherein said controller is operable to prohibit said decryption unit from decrypting the encrypted digital data when said encryption unit fails to create an encryption key.

4. The digital data recording apparatus according to claim 1, wherein the security levels of the encryption systems in which said plurality of encryption sub-units re-encrypt the decrypted digital data are lower than the security levels of encryption systems in which encrypted digital data to be received by said communication unit have been encrypted.

5. The digital data recording apparatus according to claim 1, wherein

the encrypted digital data received by said communication unit is encrypted in one of the encryption systems having different security levels and includes attribute information indicating the one of the encryption systems in which the encrypted digital data has been encrypted,

said decryption unit includes a plurality of decryption sub-units operable to decrypt the encrypted digital data that have been encrypted in the encryption systems, and

said controller is operable to determine the one of the encryption systems in which the encrypted digital data has been encrypted according to the attribute information, and to control said decryption unit so that one of said plurality of decryption sub-units corresponding to the determined one of the encryption systems decrypts the encrypted digital data.

6. The digital data recording apparatus according to claim 5, wherein said controller is operable to determine the accounting value according to said one of said decryption sub-units that has decrypted the encrypted digital data and said one of said encryption sub-units that has re-encrypted the decrypted digital data, and to control said accounting unit so that said accounting unit conducts the accounting process according to the determined accounting value.

7. A digital data recording method of recording digital data on a recording medium, said method comprising:

receiving encrypted digital data via a digital network;

decrypting the encrypted digital data received in said receiving of the encrypted digital data;

re-encrypting decrypted digital data in one of a plurality of encryption systems having different security levels;

recording digital data that has been re-encrypted in said re-encrypting of the decrypted digital data on the recording medium;

conducting an accounting process via the digital network; and

controlling said decrypting of the encrypted digital data, said re-encrypting of the decrypted digital data, and said conducting of the accounting process, wherein said re-encrypting of the decrypted digital data is controlled to re-encrypt the digital data that has been decrypted in said decrypting of the encrypted digital data by using one of the plurality of encryption systems, an accounting value is determined according to the one of the plurality of encryption systems used to re-encrypt the decrypted digital data, and said conducting of the accounting process is controlled to conduct the accounting process according to the determined accounting value.

8. The digital data recording method according to claim 7, wherein:

the encrypted digital data received in said receiving of the encrypted digital data has been encrypted in one of the plurality of encryption systems having different security levels and includes attribute information indicating the one of the plurality of encryption systems in which the encrypted digital data has been encrypted;

said method further comprising determining the one of the plurality of encryption systems according to the attribute information; and

said decrypting of the encrypted digital data decrypts the encrypted digital data according to the determined one of the plurality of encryption systems as determined in said determining of the one of the plurality of encryption systems.

9. A computer-readable recording medium that is applied to a digital data recording apparatus for recording digital data on another recording medium, said computer-readable recording medium having a program stored thereon to control a computer to execute a method of recording the digital data on the another recording medium, said method comprising:

receiving encrypted digital data via a digital network;

decrypting the encrypted digital data received in said receiving of the encrypted digital data;

re-encrypting decrypted digital data in one of a plurality of encryption systems having different security levels;

recording digital data that has been re-encrypted in said re-encrypting of the decrypted digital data on the recording medium;

conducting an accounting process via the digital network; and

controlling said decrypting of the encrypted digital data, said re-encrypting of the decrypted digital data, and said conducting of the accounting process, wherein said re-encrypting of the decrypted digital data is controlled to re-encrypt the digital data that has been decrypted in said decrypting of the encrypted digital data by using one of the plurality of encryption systems, an accounting value is determined according to the one of the plurality of encryption systems used to re-encrypt the decrypted digital data, and said conducting of the accounting process is controlled to conduct the accounting process according to the determined accounting value.

10. The computer-readable recording medium according to claim 9, wherein:

the encrypted digital data received in said receiving of the encrypted digital data has been encrypted in one of the plurality of encryption systems having different security levels and includes attribute information indicating the one of the plurality of encryption systems in which the encrypted digital data has been encrypted;

said method further comprising determining the one of the plurality of encryption systems according to the attribute information; and

said decrypting of the encrypted digital data decrypts the encrypted digital data according to the determined one of the plurality of encryption systems as determined in said determining of the one of the plurality of encryption systems.