Information-signal encrypting apparatus and information-signal decrypting apparatus

• US 20050069139A1
• Filed: 08/26/2004
• Published: 03/31/2005
• Est. Priority Date: 09/26/2003
• Status: Active Grant

• Current Assignee: JVC Kenwood Corporation
• Original Assignee: Victor Company of Japan Limited (JVC Kenwood Corporation)
• Inventors: Higurashi, Seiji
• Granted Patent: US 7,661,001 B2
• Time in Patent Office: Days
• US Class Current: 380/284
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 21/62 Protecting access to data via a platform, e.g. using keys or access control rules
• CPC Class Codes: G06F 21/78 to assure secure storage of data address-based protection against unauthorised use of memory G06F12/14; record carriers for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: G06F 2221/2107 File encryption
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/40975 using encryption therefor
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• 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 20/00195 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 20/00231 wherein the key is obtained from a local external medium, e.g. a card
• 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

Abstract

In an apparatus for encrypting an information signal into an encryption-resultant signal, a first encryption key peculiar to the present apparatus is generated. Key information is read out from a replaceable recording medium. A decision is made as to whether or not the read-out key information has been generated by an apparatus different from the present apparatus. A second encryption key is generated in response to the read-out key information when it is decided that the read-out key information has been generated by an apparatus different from the present apparatus. One is selected from the first encryption key and the second encryption key as a final encryption key. An information signal is encrypted in response to the final encryption key.

Claims

1. An apparatus for encrypting an information signal into an encryption-resultant signal, comprising:

first means for generating a first encryption key peculiar to the present apparatus;

second means for reading key information from a replaceable recording medium;

third means for deciding whether or not the key information read by the second means has been generated by an apparatus different from the present apparatus;

fourth means for generating a second encryption key in response to the key information read by the second means when the third means decides that the key information has been generated by an apparatus different from the present apparatus;

fifth means for selecting one from the first encryption key generated by the first means and the second encryption key generated by the fourth means as a final encryption key; and

sixth means for encrypting an information signal in response to the final encryption key selected by the fifth means.

2. An apparatus as recited in claim 1, wherein the fifth means comprises means for selecting the second encryption key as the final encryption key when the fourth means generates the second encryption key.

3. An apparatus as recited in claim 1, further comprising:

seventh means for reading a flag from the recording medium;

eighth means for deciding whether or not the flag read by the seventh means is in a prescribed state; and

ninth means for writing encryption-key-generating information for generation of the first encryption key into the recording medium when the eighth means decides that the flag is in the prescribed state;

wherein the second means comprises means for reading the encryption-key-generating information from the recording medium as the key information.

9. An apparatus as recited in claim 1, further comprising:

a digital IO interface;

seventh means for reading a machine ID signal from the replaceable recording medium;

eighth means for deciding whether or not the replaceable recording medium is assigned to an apparatus different from the present apparatus;

ninth means for identifying an apparatus having a machine ID signal identical with the machine ID signal read by the seventh means when the eighth means decides that the replaceable recording medium is assigned to an apparatus different from the present apparatus;

tenth means provided in the first means for using key base information to generate the first encryption key;

eleventh means for encrypting the key base information into encryption-resultant key base information in response to the key information read by the second means; and

twelfth means for sending the encryption-resultant key base information generated by the eleventh means to the apparatus identified by the ninth means via the digital IO interface.

4. An apparatus for decrypting an encryption-resultant information signal, comprising:

first means for generating a first encryption key peculiar to the present apparatus;

second means for reading key information from a replaceable recording medium;

third means for deciding whether or not the key information read by the second means is generated by an apparatus different from the present apparatus;

fourth means for generating a second encryption key in response to the key information read by the second means when the third means decides that the key information is generated by an apparatus different from the present apparatus;

fifth means for selecting one from the first encryption key generated by the first means and the second encryption key generated by the fourth means as a final encryption key; and

sixth means for decrypting an encryption-resultant information signal in response to the final encryption key selected by the fifth means to recover an original information signal.

5. An encrypting/decrypting apparatus which can operate in either a first mode or a second mode, comprising:

first means for implementing one of encryption and decryption of an information signal in response to a first encryption key during the first mode of operation;

second means for implementing one of encryption and decryption of an information signal in response to a second encryption key during the second mode of operation;

third means for generating the first encryption key;

fourth means for using the first encryption key as a master key during the first mode of operation;

fifth means for recording master key information for generation of the master key on a replaceable recording medium assigned to an apparatus different from the present apparatus during the first mode of operation;

sixth means for reading master key information from a replaceable recording medium assigned to the present apparatus during the second mode of operation; and

seventh means for generating the second encryption key in response to the master key information read by the sixth means during the second mode of operation.

6. An encrypting apparatus as recited in claim 5, wherein the seventh means comprises:

means for generating second key information in response to the master key information read by the sixth means and ID information peculiar to the present apparatus;

a memory;

means for storing the second key information into the memory; and

means for generating the master key being the second encryption key in response to the second key information and the ID information peculiar to the present apparatus.

7. An apparatus comprising:

first means for generating an individual encryption key peculiar to the present apparatus;

second means for reading key information from a removable recording medium;

third means for generating a master encryption key in response to the key information read by the second means;

fourth means for selecting one from the individual encryption key generated by the first means and the master encryption key generated by the third means as a final encryption key; and

fifth means for processing an information signal in response to the final encryption key selected by the fourth means.

8. A system comprising:

a master machine;

a slave machine;

a removable recording medium;

a first memory provided in the master machine for storing a master-key base information peculiar to the master machine;

first means for writing the master-key base information into the removable recording medium from the first memory;

a second memory provided in the slave machine for storing a slave-key base information peculiar to the slave machine;

second means provided in the slave machine for generating a first encryption key in response to the slave-key base information stored in the second memory;

third means for reading the master-key base information from the removable recording medium;

fourth means provided in the slave machine for generating a second encryption key in response to the master-key base information read by the third means;

fifth means provided in the slave machine for selecting one from the first encryption key generated by the second means and the second encryption key generated by the fourth means as a final encryption key; and

sixth means provided in the slave machine for processing an information signal in response to the final encryption key selected by the fifth means.

10. An apparatus for encrypting an information signal into an encryption-resultant signal, comprising:

first means for generating a first encryption key peculiar to the present apparatus;

second means provided in the first means for using key base information to generate the first encryption key;

a digital IO interface for receiving encryption-resultant key information;

third means for decrypting the encryption-resultant key information received by the digital IO interface into decryption-resultant key information in response to the key base information;

fourth means for generating a second encryption key in response to the decryption-resultant key information generated by the third means;

fifth means for selecting one from the first encryption key generated by the first means and the second encryption key generated by the fourth means as a final encryption key; and

sixth means for encrypting an information signal in response to the final encryption key selected by the fifth means.

11. An apparatus for decrypting an encryption-resultant information signal, comprising:

first means for generating a first encryption key peculiar to the present apparatus;

second means provided in the first means for using key base information to generate the first encryption key;

a digital IO interface for receiving encryption-resultant key information;

third means for decrypting the encryption-resultant key information received by the digital IO interface into decryption-resultant key information in response to the key base information;

fourth means for generating a second encryption key in response to the decryption-resultant key information generated by the third means;

fifth means for selecting one from the first encryption key generated by the first means and the second encryption key generated by the fourth means as a final encryption key; and

sixth means for decrypting an encryption-resultant information signal in response to the final encryption key selected by the fifth means to recover an original information signal.