Secure multimedia transfer system

• US 20050108519A1
• Filed: 12/18/2003
• Published: 05/19/2005
• Est. Priority Date: 03/02/2000
• Status: Active Grant

• Current Assignee: TiVo Solutions Inc. (Adeia Inc.)
• Original Assignee: TiVo Inc. (Adeia Inc.)
• Inventors: Platt, David, Barton, James M.
• Granted Patent: US 8,812,850 B2
• Time in Patent Office: Days
• US Class Current: 713/155
• CPC Class Codes: G06F 21/33 using certificates
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 2463/062 applying encryption of the keys
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04L 9/0897 involving additional devices, e.g. trusted platform module [TPM], smartcard or USB
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• 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 21/26613 for generating or managing keys in general key distribution for secret or secure communication involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP] H04L9/083; network support of key management H04L63/06; key management for network security in communication control or processing H04W12/04
• CPC Class Codes: H04N 21/4405 involving video stream decryption

Abstract

A method and apparatus for secure multimedia transfer provides an encrypted data transfer system that makes transferring multimedia content from a client to any incompatible system or to a system outside the location of the client very difficult.

Claims

1. A method for securely transferring multimedia content within a network, the method comprising the computer-implemented steps of:

providing a main server;

providing a database on the main server that contains registered client systems and corresponding information;

wherein a user selects a set of clients from the database that he wants to share or transfer media between;

wherein the main server creates a digital certificate that identifies the set of clients; and

wherein the digital certificate includes each client'"'"'s serial number and its corresponding public encryption key.

2. A method as recited in claim 1, wherein the user assigns a name to a client, and wherein the name that the user has assigned to the client is inserted into the certificate.

3. A method as recited in claim 1, wherein an expiration date is included in the certificate.

4. A method as recited in claim 1, further comprising the step of:

sending the certificate to each client listed in the certificate.

5. A method as recited in claim 4, wherein a digital signature identifying the main server is included in the certificate.

6. A method as recited in claim 5, wherein each client verifies the certificate by validating the digital signature in the certificate.

7. A method as recited in claim 1, wherein a client finds its peers listed in the certificate.

8. A method as recited in claim 1, wherein the client systems are digital video recorders (DVR).

9. A method as recited in claim 1, wherein the user designates a content server from among the clients listed in the certificate as a source of multimedia content, and wherein the content server can be a PC, digital video recorder (DVR), or other type of data server.

10. A method as recited in claim 9, wherein the content server creates a strongly encrypted connection with a client by creating a random strong key, wherein the content server encrypts the strong key using the client'"'"'s public key from the certificate, and wherein the content server sends the encrypted strong key to the client.

11. A method as recited in claim 10, wherein the client decrypts the strong key using its private key, and wherein the strong key is used to encrypt communications between the content server and the client.

12. A method as recited in claim 11, wherein the client requests certain recorded content from the content server.

13. A method as recited in claim 12, wherein the content server encrypts a recording key used to encrypt the requested recorded content using the strong key, and wherein the content server sends the encrypted recording key and the requested recorded content to the client.

14. A method as recited in claim 13, wherein the client decrypts the recording key using the strong key and stores the recording key, wherein the client writes the requested recorded content directly to its storage device without decoding it, and wherein when the client plays back the recorded content, it decodes the content on the fly using the recording key.

15. A method as recited in claim 1, further comprising the steps of:

providing a content server; and

wherein the content server contains a plurality of multimedia content.

16. A method as recited in claim 15, wherein the content server creates a strongly encrypted connection with a client by creating a random strong key, wherein the content server encrypts the strong key using the client'"'"'s public key from the certificate, and wherein the content server sends the encrypted strong key to the client.

17. A method as recited in claim 16, wherein the client decrypts the strong key using its private key, and wherein the strong key is used to encrypt communications between the content server and the client.

18. A method as recited in claim 17, wherein the client requests certain recorded content from the content server.

19. A method as recited in claim 18, wherein the content server encrypts a recording key used to encrypt the requested recorded content using the strong key, and wherein the content server sends the encrypted recording key and the requested recorded content to the client.

20. A method as recited in claim 19, wherein the client decrypts the recording key using the strong key and stores the recording key, wherein the client writes the requested recorded content directly to its storage device without decoding it, and wherein when the client plays back the recorded content, it decodes the content on the fly using the recording key.

21. A method for preserving coherency of a computer'"'"'s secure cache, the method comprising the computer-implemented steps of:

providing a first computer;

providing a second computer;

creating a strong communications key on the first computer;

storing the strong communications key on the first computer;

encrypting the strong communications key using the public key of the second computer;

sending the encrypted strong communications key to the second computer; and

wherein the second computer checks its local cache for an entry from the first computer and, if an entry exists, performs a comparison between a stored encrypted strong communications key in its local cache and the received encrypted strong communications key.

22. A method as recited in claim 21, wherein the second computer decrypts the strong communications key and stores the strong communications key in its local cache along with the encrypted strong communications key and the first computer'"'"'s machine serial number.

23. A method as recited in claim 21, wherein upon restart, the second computer requests the strong communications key from the first computer.

24. A method as recited in claim 23, wherein the first computer encrypts its stored strong communications key using the second computer'"'"'s public key and sends the encrypted strong communications key to the second computer.

25. A method as recited in claim 21, wherein if the comparison shows that the two keys are equal, then the second computer uses the decrypted strong communications key stored in its local cache and wherein if the comparison shows that the two keys are not equal, then the second computer decrypts the received strong communications key and stores the decrypted strong communications key, the encrypted strong communications key, and the first computer'"'"'s machine serial number in its local cache.

26. An apparatus for securely transferring multimedia content within a network, comprising:

a main server;

a database on the main server that contains registered client systems and corresponding information;

wherein a user selects a set of clients from the database that he wants to share or transfer media between;

wherein the main server creates a digital certificate that identifies the set of clients; and

wherein the digital certificate includes each client'"'"'s serial number and its corresponding public encryption key.

27. An apparatus as recited in claim 26, wherein the user assigns a name to a client, and wherein the name that the user has assigned to the client is inserted into the certificate.

28. An apparatus as recited in claim 26, wherein an expiration date is included in the certificate.

29. An apparatus as recited in claim 26, further comprising:

means for sending the certificate to each client listed in the certificate.

30. An apparatus as recited in claim 29, wherein a digital signature identifying the main server is included in the certificate.

31. An apparatus as recited in claim 30, wherein each client verifies the certificate by validating the digital signature in the certificate.

32. An apparatus as recited in claim 26, wherein a client finds its peers listed in the certificate.

33. An apparatus as recited in claim 26, wherein the client systems are digital video recorders (DVR).

34. An apparatus as recited in claim 26, wherein the user designates a content server from among the clients listed in the certificate as a source of multimedia content, and wherein the content server can be a PC, digital video recorder (DVR), or other type of data server.

35. An apparatus as recited in claim 34, wherein the content server creates a strongly encrypted connection with a client by creating a random strong key, wherein the content server encrypts the strong key using the client'"'"'s public key from the certificate, and wherein the content server sends the encrypted strong key to the client.

36. An apparatus as recited in claim 35, wherein the client decrypts the strong key using its private key, and wherein the strong key is used to encrypt communications between the content server and the client.

37. An apparatus as recited in claim 36, wherein the client requests certain recorded content from the content server.

38. An apparatus as recited in claim 37, wherein the content server encrypts a recording key used to encrypt the requested recorded content using the strong key, and wherein the content server sends the encrypted recording key and the requested recorded content to the client.

39. An apparatus as recited in claim 38, wherein the client decrypts the recording key using the strong key and stores the recording key, wherein the client writes the requested recorded content directly to its storage device without decoding it, and wherein when the client plays back the recorded content, it decodes the content on the fly using the recording key.

40. An apparatus as recited in claim 26, further comprising:

a content server; and

wherein the content server contains a plurality of multimedia content.

41. An apparatus as recited in claim 40, wherein the content server creates a strongly encrypted connection with a client by creating a random strong key, wherein the content server encrypts the strong key using the client'"'"'s public key from the certificate, and wherein the content server sends the encrypted strong key to the client.

42. An apparatus as recited in claim 41, wherein the client decrypts the strong key using its private key, and wherein the strong key is used to encrypt communications between the content server and the client.

43. An apparatus as recited in claim 42, wherein the client requests certain recorded content from the content server.

44. An apparatus as recited in claim 43, wherein the content server encrypts a recording key used to encrypt the requested recorded content using the strong key, and wherein the content server sends the encrypted recording key and the requested recorded content to the client.

45. An apparatus as recited in claim 44, wherein the client decrypts the recording key using the strong key and stores the recording key, wherein the client writes the requested recorded content directly to its storage device without decoding it, and wherein when the client plays back the recorded content, it decodes the content on the fly using the recording key.

46. An apparatus for preserving coherency of a computer'"'"'s secure cache, comprising:

a first computer;

a second computer;

means for creating a strong communications key on the first computer;

means for storing the strong communications key on the first computer;

means for encrypting the strong communications key using the public key of the second computer;

means for sending the encrypted strong communications key to the second computer; and

wherein the second computer checks its local cache for an entry from the first computer and, if an entry exists, performs a comparison between a stored encrypted strong communications key in its local cache and the received encrypted strong communications key.

47. An apparatus as recited in claim 46, wherein the second computer decrypts the strong communications key and stores the strong communications key in its local cache along with the encrypted strong communications key and the first computer'"'"'s machine serial number.

48. An apparatus as recited in claim 46, wherein upon restart, the second computer requests the strong communications key from the first computer.

49. An apparatus as recited in claim 48, wherein the first computer encrypts its stored strong communications key using the second computer'"'"'s public key and sends the encrypted strong communications key to the second computer.

50. An apparatus as recited in claim 46, wherein if the comparison shows that the two keys are equal, then the second computer uses the decrypted strong communications key stored in its local cache and wherein if the comparison shows that the two keys are not equal, then the second computer decrypts the received strong communications key and stores the decrypted strong communications key, the encrypted strong communications key, and the first computer'"'"'s machine serial number in its local cache.

51. A computer-readable medium carrying one or more sequences of instructions for securely transferring multimedia content within a network, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

providing a main server;

providing a database on the main server that contains registered client systems and corresponding information;

wherein a user selects a set of clients from the database that he wants to share or transfer media between;

wherein the main server creates a digital certificate that identifies the set of clients; and

wherein the digital certificate includes each client'"'"'s serial number and its corresponding public encryption key.

52. A method as recited in claim 51, wherein the user assigns a name to a client, and wherein the name that the user has assigned to the client is inserted into the certificate.

53. A method as recited in claim 51, wherein an expiration date is included in the certificate.

54. A method as recited in claim 51, further comprising the step of:

sending the certificate to each client listed in the certificate.

55. A method as recited in claim 54, wherein a digital signature identifying the main server is included in the certificate.

56. A method as recited in claim 55, wherein each client verifies the certificate by validating the digital signature in the certificate.

57. A method as recited in claim 51, wherein a client finds its peers listed in the certificate.

58. A method as recited in claim 51, wherein the client systems are digital video recorders (DVR).

59. A method as recited in claim 51, wherein the user designates a content server from among the clients listed in the certificate as a source of multimedia content, and wherein the content server can be a PC, digital video recorder (DVR), or other type of data server.

60. A method as recited in claim 59, wherein the content server creates a strongly encrypted connection with a client by creating a random strong key, wherein the content server encrypts the strong key using the client'"'"'s public key from the certificate, and wherein the content server sends the encrypted strong key to the client.

61. A method as recited in claim 60, wherein the client decrypts the strong key using its private key, and wherein the strong key is used to encrypt communications between the content server and the client.

62. A method as recited in claim 61, wherein the client requests certain recorded content from the content server.

63. A method as recited in claim 62, wherein the content server encrypts a recording key used to encrypt the requested recorded content using the strong key, and wherein the content server sends the encrypted recording key and the requested recorded content to the client.

64. A method as recited in claim 63, wherein the client decrypts the recording key using the strong key and stores the recording key, wherein the client writes the requested recorded content directly to its storage device without decoding it, and wherein when the client plays back the recorded content, it decodes the content on the fly using the recording key.

65. A method as recited in claim 51, further comprising the steps of:

providing a content server; and

wherein the content server contains a plurality of multimedia content.

66. A method as recited in claim 65, wherein the content server creates a strongly encrypted connection with a client by creating a random strong key, wherein the content server encrypts the strong key using the client'"'"'s public key from the certificate, and wherein the content server sends the encrypted strong key to the client.

67. A method as recited in claim 66, wherein the client decrypts the strong key using its private key, and wherein the strong key is used to encrypt communications between the content server and the client.

68. A method as recited in claim 67, wherein the client requests certain recorded content from the content server.

69. A method as recited in claim 68, wherein the content server encrypts a recording key used to encrypt the requested recorded content using the strong key, and wherein the content server sends the encrypted recording key and the requested recorded content to the client.

70. A method as recited in claim 69, wherein the client decrypts the recording key using the strong key and stores the recording key, wherein the client writes the requested recorded content directly to its storage device without decoding it, and wherein when the client plays back the recorded content, it decodes the content on the fly using the recording key.

71. A computer-readable medium carrying one or more sequences of instructions for preserving coherency of a computer'"'"'s secure cache, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

providing a first computer;

providing a second computer;

creating a strong communications key on the first computer;

storing the strong communications key on the first computer;

encrypting the strong communications key using the public key of the second computer;

sending the encrypted strong communications key to the second computer; and

wherein the second computer checks its local cache for an entry from the first computer and, if an entry exists, performs a comparison between a stored encrypted strong communications key in its local cache and the received encrypted strong communications key.

72. A method as recited in claim 71, wherein the second computer decrypts the strong communications key and stores the strong communications key in its local cache along with the encrypted strong communications key and the first computer'"'"'s machine serial number.

73. A method as recited in claim 71, wherein upon restart, the second computer requests the strong communications key from the first computer.

74. A method as recited in claim 73, wherein the first computer encrypts its stored strong communications key using the second computer'"'"'s public key and sends the encrypted strong communications key to the second computer.

75. A method as recited in claim 71, wherein if the comparison shows that the two keys are equal, then the second computer uses the decrypted strong communications key stored in its local cache and wherein if the comparison shows that the two keys are not equal, then the second computer decrypts the received strong communications key and stores the decrypted strong communications key, the encrypted strong communications key, and the first computer'"'"'s machine serial number in its local cache.