METHOD AND APPARATUS FOR ENCRYPTING MEDIA PROGRAMS FOR LATER PURCHASE AND VIEWING

• US 20080279386A1
• Filed: 07/14/2008
• Published: 11/13/2008
• Est. Priority Date: 09/21/2001
• Status: Active Grant

• Current Assignee: DIRECTV, LLC (AT&T, Inc.)
• Original Assignee: The DIRECTV Group, Inc. (AT&T, Inc.)
• Inventors: Cocchi, Ronald P., James, Thomas H., Kahn, Raynold M., Klauss, Peter M., Gagnon, Gregory J., Curren, Christopher P., Ha, David D.
• Granted Patent: US 8,677,152 B2
• Time in Patent Office: Days
• US Class Current: 380/278
• CPC Class Codes: A63F 2300/407 Data transfer via internet
• CPC Class Codes: G06F 21/445 by mutual authentication, e.g. between devices or programs
• CPC Class Codes: G06F 21/602 Providing cryptographic facilities or services
• CPC Class Codes: G06F 21/73 by creating or determining hardware identification, e.g. serial numbers
• CPC Class Codes: G06F 2221/2107 File encryption
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/4147 PVR [Personal Video Recorder] H04N5/76 takes precedence ; arrangements for broadcast with accumulation-type receivers H04H20/40
• CPC Class Codes: H04N 21/4367 Establishing a secure communication between the client and a peripheral device or smart card
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/835 Generation of protective data, e.g. certificates protecting software against unauthorised usage in a vending or licensing environment G06F21/10
• 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 system and method for storing and retrieving program material for subsequent replay is disclosed. The method includes accepting a receiver ID associated with a receiver key stored in a memory of the receiver, determining a pairing key for encrypting communications between the conditional access module and the receiver, encrypting the pairing key with the receiver key, and transmitting a message comprising the encrypted pairing key to the receiver. The apparatus comprises a receiver for receiving a data stream transmitting a media program encrypted according to a media encryption key and an encrypted media encryption key and a conditional access module, communicatively coupleable with the receiver.

Claims

1-13. -13. (canceled)

14. A method of controlling access to a stored media program, comprising the steps of:

receiving a data stream including the media program encrypted according to a media encryption key;

decrypting the encrypted media program;

generating a copy protection key;

encrypting the decrypted data stream using the copy protection key.

15. The method of claim 14, wherein the copy protection key is generated from a content identifier and a family key.

16. The method of claim 15, wherein the content identifier is obtained from a program guide.

17. The method of claim 15, wherein the content identifier is entered by the user.

18. The method of claim 15, wherein the content identifier uniquely identifies the media program.

19. The method of claim 15, wherein the content identifier further comprises copy control information.

20. The method of claim 14, further comprising the steps of:

receiving an encrypted family key; and

decrypting the family key using a receiver key substantially uniquely associated with the media program receiver.

21. The method of claim 20, wherein the encrypted family key is received in response to a service request including a unique identifier of a media program receiver.

22. The method of claim 21, wherein the unique identifier is user-readable.

23. The method of claim 20, wherein the receiver key is user-unreadable,

24. The method of claim 14, wherein the media encryption key is time-variant.

25. The method of claim 14, wherein the copy protection key is stored in a transport module.

26. The method of claim 14, wherein the data stream includes an encrypted media encryption key (EI(CW)), and the step of decrypting the encrypted media program comprises the steps of:

decrypting the encrypted media encryption key (EI(CW)) to produce the media encryption key (CW);

encrypting the decrypted media encryption key (CW) according to a pairing key;

decrypting the encrypted media encryption key EP(CW) using the pairing key;

decrypting the media program with the media encryption key (CW).

27. The method of claim 26, wherein the first encryption key E1(CW) is decrypted in the conditional access module and encrypted according to the pairing key in the conditional access module.

28. The method of claim 14, further comprising the steps of:

receiving an encrypted pairing key;

decrypting the encrypted pairing key using a receiver key substantially uniquely associated with the media program receiver.

29. The method of claim 28, further comprising the step of:

storing the decrypted pairing key in the receiver.

30. The method of claim 28, wherein the encrypted pairing key is received in response to a service request including a unique identifier of a media program receiver.

31. The method of claim 28, wherein the receiver key is unique to the media program receiver.

32. The method of claim 14, further comprising the step of:

storing the encrypted data stream in a storage device locally accessible to the receiver.

33. The method of claim 32, further comprising the step of storing the content identifier in the storage device.

34. The method of claim 20, further comprising the step of:

generating the copy protection key from the content identifier and the family key;

decrypting the encrypted data stream using the copy protection key.

35. The method of claim 34, further comprising the steps of:

accepting a selection of the media program; and

reading the content identifier associated with the selected media program.

36. The method of claim 34, wherein the copy protection key is generated from the content identifier and the family in a security module.

37. The method of claim 34, further comprising the step of storing the copy protection key.

38. The method of claim 37, wherein the copy protection key is stored in a transport module.

39. The method of claim 34, further comprising the step of:

providing the decrypted data stream to a presentation device.

40. The method of claim 14, further comprising the step of:

transmitting the encrypted data stream to a second receiver.

41. The method of clam 40, further comprising the steps of:

generating a copy protection key in the second receiver from the content identifier and the family key; and

decrypting the encrypted data stream using the copy protection key.

42. The method of claim 41, further comprising the steps of:

accepting a selection of the media program in the second receiver; and

reading the content identifier associated with the media program from the storage device.

43. The method of claim 41, wherein the copy protection key is generated in a security module in the second receiver.

44. The method of claim 41, further comprising the step of storing the session key in the second receiver.

45. The method of claim 41, further comprising the step of providing the decrypted data stream to a presentation device communicatively coupled to the second receiver.

51. The method of claim 45, wherein the content identifier is obtained from a program guide.

52. The method of claim 45, wherein the content identifier is user-entered.

53. The method of claim 45, wherein the content identifier uniquely identifies the media program.

54. The method of claim 45, wherein the content identifier further comprises copy control information.

46. A method of controlling access to a media program, comprising the steps of:

receiving a data stream including the media program encrypted according to a media encryption key (CW) and an encrypted media encryption key (CW);

generating a copy protection key (CP) from a content identifier and a family key; and

further encrypting the data stream using the copy protection key (CP).

47. The method of claim 46, further comprising the step of:

storing the further encrypted data stream.

48. The method of claim 46, wherein the first encryption key is a time-variant key.

49. The method of claim 47, wherein the further encrypted data stream is stored in a storage device locally accessible to the receiver.

50. The method of claim 49, further comprising the steps of:

storing the copy protection key in a transport module.

55. The method of claim 47, further comprising the steps of:

receiving an encrypted family key; and

decrypting the family key using receiver key associated unique to the media program receiver

56. The method of claim 55, wherein the encrypted family key is received in response to a service request including a unique identifier of a media program receiver.

57. The method of claim 47, wherein receiver key is user-unreadable.

58. The method of claim 55, further comprising the steps of:

generating the copy protection key from the content identifier and the family key;

reading the stored further encrypted data stream;

decrypting the stored further encrypted data stream using the copy protection key to produce the media program encrypted according to the media encryption key (CW) and to produce the encrypted media encryption key;

decrypting the encrypted media encryption key and re-encrypting the media encryption key according to a pairing key;

decrypting the re-encrypted media encryption key using a pairing key to produce the media encryption key (CW); and

decrypting the media program using the first encryption key (CW).

59. The method of claim 58, wherein the media encryption key is decrypted and re-encrypted in a conditional access module, and the pairing key is stored in the conditional access module.

60. The method of claim 59, wherein the re-encrypted media encryption key is decrypted and stored in a receiver removably communicatively coupleable with the conditional access module.

61. The method of claim 58, further comprising the step of storing the copy protection key in a receiver.

62. The method of claim 58, further comprising the steps of:

accepting a selection of the media program in the second receiver; and

reading the content identifier associated with the media program from the storage device.

63. The method of claim 58, wherein the step of decrypting the re-encrypted media encryption key using a pairing key to produce the media encryption key comprises the steps of:

receiving an encrypted pairing key; and

decrypting the encrypted pairing key using a receiver key.

64. The method of claim 63, wherein the encrypted pairing key is received in response to a service request including a unique identifier of a receiver.

65. The method of claim 63, further comprising the step of storing the pairing key in a receiver.

66. The method of claim 58, further comprising the step of:

providing the decrypted media program to a presentation device.

67. The method of claim 58, further comprising the steps of:

re-encrypting the decrypted media program according to the copy protection key;

storing the re-encrypted media program; and

decrypting the re-encrypted media program according to the copy protection key.

68. The method of claim 67, further comprising the step of:

regenerating the copy protection key from the content identifier and the family key.

69. The method of claim 68, wherein the decrypted media program is re-encrypted in response to at least one of a set of commands requiring re-storage of the media program.

70. The method of claim 69, wherein the set of commands includes a command selected from the group comprising:

a pause command;

a rewind command;

a fast forward command; and

a reverse command.

71. The method of claim 67, further comprising the step of:

providing the decrypted media program to a presentation device.

72. The method of claim 67, further comprising the step of:

providing the decrypted media program to a second receiver.

73. An apparatus for receiving media programs, comprising:

a receiver, for receiving a data stream transmitting a media program encrypted according to a media encryption key (CW) and an encrypted media encryption key, the receiver having;

a first decryptor, for decrypting a message from the conditional access module according to a pairing key (PI), the message comprising the media encryption key (CW);

a conditional access module, communicatively coupleable to the receiver, the conditional access module having

a second decryptor for decrypting the encrypted media encryption key (CW); and

a first encryptor, for encrypting messages with the receiver according to the pairing key (PK).

74. The apparatus of claim 73, wherein the messages include the media encryption key (CW).

75. The apparatus of claim 73, wherein:

the receiver further comprises a secure memory having a receiver key (RK);

data stream further comprises the pairing key (PK) encrypted according to the receiver key (RK); and

the first decryptor further decrypts the encrypted pairing key (PK) with the receiver key (RK) to produce the pairing key (PK).

76. The apparatus of claim 75, wherein

the data stream further comprises a family key (FK) encrypted according to the receiver key (RK);

and

the first decryptor further decrypts the encrypted family key (FK) with the receiver key (RK) to produce the family key (FK).

77. The apparatus of claim 76, wherein

the first decryptor generates a copy protection (CP) key from the family key.

78. The apparatus of claim 77, wherein the receiver comprises a first encryptor for encrypting the media program according to the copy protection (CP) key and a second decryptor for decrypting the media program according to the copy protection (CP) key.

79. The apparatus of claim 78, further comprising a data storage device coupled to the receiver, the data storage device for storing and retrieving the media program encrypted according to the copy protection (CP) key.

80-83. -83. (canceled)

84. An apparatus for controlling access to a stored media program, comprising:

means for receiving a data stream including the media program encrypted according to a media encryption key;

means for decrypting the encrypted media program;

means for generating a copy protection key; and

means for encrypting the decrypted data stream using the copy protection key.

85. The apparatus of claim 84, further comprising:

means for receiving an encrypted family key; and

means for decrypting the family key using a receiver key substantially uniquely associated with the media program receiver.

86. The apparatus of claim 85, further comprising:

means for generating the copy protection key from the content identifier and the family key; and

means for decrypting the encrypted data stream using the copy protection key.

87. The apparatus of claim 84, wherein the data stream includes an encrypted media encryption key (EI(CW)), and the means for decrypting the media program comprises:

means for decrypting the encrypted media encryption key (EI(CW)) to produce the media encryption key;

means for encrypting the decrypted media encryption key (CW) according to a pairing key;

means for decrypting the encrypted media encryption key EP(CW) using the pairing key; and

means for decrypting the media program with the media encryption key (CW).

88. The apparatus of claim 84, further comprising:

means for receiving an encrypted pairing key; and

means for decrypting the encrypted pairing key using a receiver key substantially uniquely associated with the media program receiver.

89. An apparatus of controlling access to a media program, comprising:

means for receiving a data stream including the media program encrypted according to a media encryption key (CW) and an encrypted media encryption key (CW);

means for generating a copy protection key from a content identifier and a family key;

means for further encrypting the data stream using the copy protection key (CP); and

means for storing the copy protection key (CP) in the receiver.

90. The apparatus of claim 89, further comprising:

means for receiving an encrypted family key; and

means for decrypting the family key using receiver key associated unique to the media program receiver.

91. The apparatus of claim 90, further comprising:

means for generating the copy protection key from the content identifier and the family key;

means for reading the stored further encrypted data stream;

means for decrypting the stored further encrypted data stream using the copy protection key to produce the media program encrypted according to the media encryption key (CW) and to produce the encrypted media encryption key;

means for decrypting the encrypted media encryption key and re-encrypting the media encryption key according to a pairing key;

means for decrypting the re-encrypted media encryption key using a pairing key to produce the media encryption key (CW); and

means for decrypting the media program using the first encryption key (CW).

92. The apparatus of claim 91, further comprising:

means for accepting a selection of the media program in the second receiver; and

means for reading the content identifier associated with the media program from the storage device.

93. The apparatus of claim 91, wherein the means for decrypting the re-encrypted media encryption key using a pairing key to produce the media encryption key comprises:

means for receiving an encrypted pairing key; and

means for decrypting the encrypted pairing key using a receiver key.

94. The apparatus of claim 91, further comprising:

means for providing the decrypted media program to a presentation device.

95. The apparatus of claim 91, further comprising:

means for re-encrypting the decrypted media program according to the copy protection key;

means for storing the re-encrypted media program; and

means for decrypting the re-encrypted media program according to the copy protection key.

96. The apparatus of claim 95, further comprising:

means for regenerating the copy protection key from the content identifier and the family key.

97. The apparatus of claim 96, wherein the decrypted media program is re-encrypted in response to at least one of a set of commands requiring re-storage of the media program.

98. A system for transmitting and receiving media programs, comprising:

a transmitter, for transmitting a data stream having a media program encrypted according to a media encryption key (CW) and an encrypted media encryption key;

a receiver, for receiving the transmitted data stream, the receiver having;

a first decryptor, for decrypting a message from the conditional access module according to a pairing key (PK), the message comprising the media encryption key (CW);

a conditional access module, communicatively coupleable to the receiver, the conditional access module having

a second decryptor for decrypting the encrypted media encryption key (CW); and

a first encryptor, for encrypting messages with the receiver according to the pairing key (PK).