COMMUNICATION SYSTEM, COMMUNICATION APPARATUS, COMMUNICATION METHOD, AND COMPUTER PROGRAM

• US 20120155642A1
• Filed: 08/30/2010
• Published: 06/21/2012
• Est. Priority Date: 09/09/2009
• Status: Abandoned Application

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nakano, Takehiko
• Application Number:
  US13/393,504
• Publication Number:
  US 20120155642A1
• Time in Patent Office: Days
• US Class Current: 380/255
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 2463/103 applying security measure for protecting copy right protecting software against unauthorised usage in a vending or licensing environment, e.g. protection the software providers copyright G06F21/10; data processing systems or methods, specially adapted for payment schemes, architectures or protocols G06Q20/00; secrecy systems or subscription systems H04N7/16
• CPC Class Codes: H04L 63/0869 for achieving mutual authentication cryptographic mechanisms or cryptographic arrangements for mutual authentication H04L9/3273
• CPC Class Codes: H04L 63/102 Entity profiles
• CPC Class Codes: H04L 9/0841 involving Diffie-Hellman or related key agreement protocols
• CPC Class Codes: H04L 9/3273 for mutual authentication network architectures or network communication protocols for achieving mutual authentication in a packet data network H04L63/0869
• CPC Class Codes: H04N 21/25816 involving client authentication restricting access to computer systems by authenticating users using a predetermined code G06F21/33; cryptographic authentication protocols H04L9/32; networks authentication protocols H04L63/08; authentication in wireless network security H04W12/06
• CPC Class Codes: H04N 21/6334 for authorisation, e.g. by transmitting a key wireless communications network key management H04W12/04; wireless communications network access security H04W12/08
• CPC Class Codes: H04W 12/61 Time-dependent

Abstract

A source apparatus and a conditional access apparatus are disclosed. The source apparatus may transmit a command to the conditional access apparatus. The conditional access apparatus may transmit a response to the command to the source apparatus. When a time elapsed between transmission of the command by the source apparatus and reception of the response by the source apparatus does not exceed a predetermined round trip time (RTT), a first authorization signal to permit the conditional access apparatus to decrypt encrypted content may be generated. Additionally, whenever a non-RTT condition is met, a second authorization signal to permit the conditional access apparatus to decrypt the content may be generated.

Claims

1. A conditional access apparatus for selectively generating a signal to permit decryption of encrypted content, the conditional access apparatus comprising:

a first authorization section configured to;

receive a command transmitted by a source apparatus;

transmit to the source apparatus a response to the command; and

generate a first authorization signal to permit decryption of the content, the first authorization signal being generated upon receipt of an indication signal indicating that a time elapsed between transmission of the command by the source apparatus and reception of the response by the source apparatus does not exceed a predetermined round trip time (RTT); and

a second authorization section configured to generate a second authorization signal to permit decryption of the content, the second authorization signal being generated whenever a non-RTT condition is met.

2. The conditional access apparatus of claim 1, further comprising a registration section configured to transmit a request to register the conditional access apparatus with the source apparatus.

3. The conditional access apparatus of claim 2, wherein the registration section is configured to:

receive a second command transmitted by the source apparatus; and

transmit to the source apparatus a second response to the second command.

4. The conditional access apparatus of claim 1, wherein at least one of the first and the second authorization signals includes a content key for decrypting the content.

5. The conditional access apparatus of claim 4, wherein at least one of the first and the second authorization sections is configured to generate the content key based on an exchange key.

6. The conditional access apparatus of claim 5, wherein the first authorization section is configured to generate the content key based on a nonce if:

the first authorization section receives the indication signal from the source apparatus; and

the received indication signal includes the nonce.

7. The conditional access apparatus of claim 1, wherein the predetermined RTT is 7 milliseconds.

8. A source apparatus for selectively generating a signal to permit a conditional access apparatus to decrypt encrypted content, the source apparatus comprising:

a first authorization section configured to;

transmit a command to the conditional access apparatus;

receive from the conditional access apparatus a response to the command; and

generate a first authorization signal to permit the conditional access apparatus to decrypt the content, the first authorization signal being generated when a time elapsed between transmission of the command and reception of the response does not exceed a predetermined round trip time (RTT); and

a second authorization section configured to generate a second authorization signal to permit the conditional access apparatus to decrypt the content, the second authorization signal being generated whenever a non-RTT condition is met.

9. The source apparatus of claim 8, further comprising a registration section configured to register at least one conditional access apparatus.

10. The source apparatus of claim 9, wherein the non-RTT condition is met when the conditional access apparatus has been registered with the source apparatus.

11. The source apparatus of claim 9, wherein the non-RTT condition is met when:

the conditional access apparatus has been registered with the source apparatus; and

the content has been;

designated as remotely accessible;

or

not designated as remotely inaccessible.

12. The source apparatus of claim 11, wherein the non-RTT condition is met only when:

the conditional access apparatus has been registered with the source apparatus; and

the content has been designated as remotely accessible.

13. The source apparatus of claim 9, wherein the registration section is configured to:

transmit a second command to the conditional access apparatus; and

receive from the conditional access apparatus a second response to the second command.

14. The source apparatus of claim 13, wherein the conditional access apparatus is registered with the source apparatus when a second time elapsed between transmission of the second command and reception of the second response does not exceed a second predetermined RTT.

15. The source apparatus of claim 9, wherein only a number of conditional access apparatuses below a threshold value can be registered with the source apparatus at any one time.

16. The source apparatus of claim 8, wherein at least one of the first and the second authorization signals includes an exchange key for generating a content key for decrypting the content.

17. The source apparatus of claim 16, wherein the at least one of the first and the second authorization signals includes a nonce for generating the content key.

18. The source apparatus of claim 8, wherein:

the first authorization section is configured to transmit the first authorization signal to the conditional access apparatus; and

the second authorization section is configured to transmit the second authorization signal to the conditional access apparatus.

19. The source apparatus of claim 8, wherein the predetermined RTT is 7 milliseconds.

20. A method for selectively generating a signal with a conditional access apparatus to permit decryption of encrypted content, the method comprising:

receiving a command transmitted by a source apparatus;

transmitting to the source apparatus a response to the command;

upon receipt of an indication signal indicating that a time elapsed between transmission of the command by the source apparatus and reception of the response by the source apparatus does not exceed a predetermined round trip time (RTT), generating a first authorization signal to permit decryption of the content; and

whenever a non-RTT condition is met, generating a second authorization signal to permit decryption of the content.

21. A method for selectively generating a signal with a source apparatus to permit a conditional access apparatus to decrypt encrypted content, the method comprising:

transmitting a command to the conditional access apparatus;

receiving from the conditional access apparatus a response to the command;

when a time elapsed between transmission of the command and reception of the response does not exceed a predetermined round trip time (RTT), generating a first authorization signal to permit the conditional access apparatus to decrypt the content; and

whenever a non-RTT condition is met, generating a second authorization signal to permit the conditional access apparatus to decrypt the content.

22. A conditional access apparatus for selectively generating a signal to permit decryption of encrypted content, the conditional access apparatus comprising:

a memory storing a program; and

a processor configured to execute the program to cause the conditional access apparatus to perform a method for selectively generating the signal, the method comprising;

receiving a command transmitted by a source apparatus;

transmitting to the source apparatus a response to the command;

upon receipt of an indication signal indicating that a time elapsed between transmission of the command by the source apparatus and reception of the response by the source apparatus does not exceed a predetermined round trip time (RTT), generating a first authorization signal to permit decryption of the content; and

whenever a non-RTT condition is met, generating a second authorization signal to permit decryption of the content.

23. A source apparatus for selectively generating a signal to permit a conditional access apparatus to decrypt encrypted content, the source apparatus comprising:

a memory storing a program; and

a processor configured to execute the program to cause the source apparatus to perform a method for selectively generating the signal, the method comprising;

transmitting a command to the conditional access apparatus;

receiving from the conditional access apparatus a response to the command;

when a time elapsed between transmission of the command and reception of the response does not exceed a predetermined round trip time (RTT), generating a first authorization signal to permit the conditional access apparatus to decrypt the content; and

whenever a non-RTT condition is met, generating a second authorization signal to permit the conditional access apparatus to decrypt the content.

24. A non-transitory, computer-readable storage medium storing a program that, when executed by a processor, causes a conditional access apparatus to perform a method for selectively generating a signal to permit decryption of encrypted content, the method comprising:

receiving a command transmitted by a source apparatus;

transmitting to the source apparatus a response to the command;

upon receipt of an indication signal indicating that a time elapsed between transmission of the command by the source apparatus and reception of the response by the source apparatus does not exceed a predetermined round trip time (RTT), generating a first authorization signal to permit decryption of the content; and

whenever a non-RTT condition is met, generating a second authorization signal to permit decryption of the content.

25. A non-transitory, computer-readable storage medium storing a program that, when executed by a processor, causes a source apparatus to perform a method for selectively generating a signal to permit a conditional access apparatus to decrypt encrypted content, the method comprising:

transmitting a command to the conditional access apparatus;

receiving from the conditional access apparatus a response to the command;

when a time elapsed between transmission of the command and reception of the response does not exceed a predetermined round trip time (RTT), generating a first authorization signal to permit the conditional access apparatus to decrypt the content; and

whenever a non-RTT condition is met, generating a second authorization signal to permit the conditional access apparatus to decrypt the content.