Audio cassette emulator with cryptographic media distribution control

• US 7,436,957 B1
• Filed: 07/29/1999
• Issued: 10/14/2008
• Est. Priority Date: 08/27/1998
• Status: Expired due to Fees

• Current Assignee: Addison M. Fischer
• Original Assignee: Addison M. Fischer
• Inventors: Fischer, Addison M., Protheroe, Robert L.
• Primary Examiner(s): Sheikh; Ayaz
• Assistant Examiner(s): AVERY, JEREMIAH L
• Application Number:
  US09/363,413
• Time in Patent Office: 3,365 Days
• Field of Search: 380/53, 380201-203, 380/229, 380/232, 380/22, 380/200, 380/241, 380/277, 380/259, 709223-229, 713/155, 713/165, 713/171, 713/182, 713/194, 713200-201, 726/26
• US Class Current: 380/53
• CPC Class Codes: G06F 12/1408 by using cryptography for digital transmission H04L9/00
• 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: 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 20/00188 involving measures which result in a restriction to authorised devices recording or reproducing contents to/from a record carrier
• 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 20/00246 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 20/00695 said measures preventing that data are read from the recording medium
• CPC Class Codes: G11B 23/049 Cassettes for special applications not otherwise provided for
• CPC Class Codes: H04N 21/4143 embedded in a Personal Computer [PC]
• CPC Class Codes: H04N 21/4627 Rights management associated to the content security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08

Abstract

A device of the same general physical size and shape as a standard audio cassette tape, but which accepts digital information from any of a variety of sources—including for example: Internet transmission, a digital computer, or memory cards (especially digital memory cards)—and plays this digital information through any, for example, standard audio tape cassette player. The device operates by converting the digital representation of the sound into magnetic signals which are presented to the read/write head of the cassette player equipment. The device allows the user of the cassette player to regulate the audio playback using conventional equipment controls such as: START, STOP, REWIND, FAST REWIND, FORWARD, FAST FORWARD, etc. The device has the same general physical dimensions of a standard audio cassette; at least one digital processor; and a slot into which electronic media such as, for example, memory cards, smart cards having a processor and a memory embodied thereon and other memory media may be inserted. Numerous sensors detect changes in at least one of the tape equipment mechanisms in the audio cassette emulator. Various cryptographic techniques are described for protecting the unauthorized distribution of audio information.

Claims

1. A method of transferring authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the method comprising:

receiving a transfer authorization request having an indicator of the first device, an indicator of the second device, and an indicator of the protected electronic content;

updating a first device history table to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

communicating a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content, and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device.

2. The method of claim 1 wherein the device cryptographic key of the second device is a symmetric key.

3. The method of claim 2 wherein the device cryptographic key of the second device is a DES key.

4. The method of claim 1 wherein the device cryptographic key of the second device is a public key having a corresponding private key stored with the second device, and protecting the content cryptographic key using the device cryptographic key of the second device includes protecting the content cryptographic key with the public key such that the second device may use the corresponding private key to gain access to the content cryptographic key.

5. The method of claim 4 wherein the public key is an RSA public key and the private key is an RSA private key.

6. The method of claim 1 wherein the content cryptographic key is a symmetric key which is used to encrypt the protected electronic content such that only the symmetric key can be used to decrypt the content.

7. The method of claim 1 further comprising receiving payment authorization information associated with the transfer authorization request, and charging a service fee based on the payment authorization information.

8. The method of claim 1 wherein updating the first device history table comprises removing a stored indicator of the protected electronic content from the first device history table.

9. The method of claim 1 wherein updating the first device history table comprises adding indicia that the protected electronic content is no longer authorized for the first device.

10. The method of claim 1 wherein the protected electronic content is audio content.

11. The method of claim 1 wherein the protected electronic content is video content.

12. The method of claim 1 wherein the protected electronic content is electronic written content.

13. The method of claim 1 wherein the indicator of the first device in the transfer authorization request is a unique serial number.

14. The method of claim 1 further comprising verifying that the first device is authorized to render the protected electronic content.

15. A system of transferring authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the system comprising:

an input for receiving a transfer authorization request having an indicator of the first device, an indicator of the second device, and an indicator of the protected electronic content;

a processor for updating a first device history table to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

an output for communicating a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content, and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device.

16. The system of claim 15 wherein the device cryptographic key of the second device is a symmetric key.

17. The system of claim 15 wherein the device cryptographic key of the second device is a public key having a corresponding private key stored with the second device, and protecting the content cryptographic key using the device cryptographic key of the second device includes protecting the content cryptographic key with the public key such that the second device may use the corresponding private key to gain access to the content cryptographic key.

18. The system of claim 15 wherein the content cryptographic key is a symmetric key which is used to encrypt the protected electronic content such that only the symmetric key can be used to decrypt the content.

19. The system of claim 15 wherein the input receives payment authorization information associated with the authorization request, and the processor charges a service fee based on the payment authorization information.

20. The system of claim 15 wherein the indicator of the first device in the transfer authorization request is a unique serial number.

21. The system of claim 15 wherein the processor verifies that the first device is authorized to render the protected electronic content.

22. A method of transferring authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the method comprising:

receiving a transfer authorization request having an indicator of the first device an indicator of the second device, and an indicator of the protected electronic content;

updating a first device history table to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

communicating a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content, and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device;

wherein the first and second devices are devices which may be inserted into a standard tape player having a plurality of conventional user controls.

23. A system of transferring authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the system comprising:

an input for receiving a transfer authorization request having an indicator of the first device, an indicator of the second device, and an indicator of the protected electronic content;

a processor for updating a first device history table to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

an output for communicating a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content, and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device;

wherein the first and second devices are devices which may be inserted into a standard tape player having a plurality of conventional user controls.

24. A method of operating a device manager to transfer authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the device manager being a different device than the first and second devices, the method comprising:

receiving, at the device manager, a transfer authorization request having an indicator of the first device, an indicator of the second device, and an indicator of the protected electronic content;

updating a first device history table stored by the device manager to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table stored by the device manager to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

communicating from the device manager a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content, and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device.

25. The method of claim 24 wherein the device cryptographic key of the second device is a symmetric key.

26. The method of claim 24 wherein the device cryptographic key of the second device is a DES key.

27. The method of claim 24 wherein the device cryptographic key of the second device is a public key having a corresponding private key stored with the second device, and protecting the content cryptographic key using the device cryptographic key of the second device includes protecting the content cryptographic key with the public key such that the second device may use the corresponding private key to gain access to the content cryptographic key.

28. The method of claim 27 wherein the public key is an RSA public key and the private key is an RSA private key.

29. The method of claim 24 wherein the content cryptographic key is a symmetric key which is used to encrypt the protected electronic content such that only the symmetric key can be used to decrypt the content.

30. The method of claim 24 further comprising receiving, at the device manager, payment authorization information associated with the transfer authorization request, and charging a service fee based on the payment authorization information.

31. The method of claim 24 wherein updating the first device history table comprises removing a stored indicator of the protected electronic content from the first device history table.

32. The method of claim 24 wherein updating the first device history table comprises adding indicia that the protected electronic content is no longer authorized for the first device.

33. The method of claim 24 wherein the protected electronic content is audio content.

34. The method of claim 24 wherein the protected electronic content is video content.

35. The method of claim 24 wherein the protected electronic content is electronic written content.

36. The method of claim 24 wherein the indicator of the first device in the transfer authorization request is a unique serial number.

37. The method of claim 24 further comprising verifying that the first device is authorized to render the protected electronic content.

38. A method of operating a device manager to transfer authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the device manager being a different device than the first and second devices, the method comprising:

receiving, at the device manager, a transfer authorization request having an indicator of the first device, an indicator of the second device, and an indicator of the protected electronic content;

updating a first device history table stored by the device manager to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table stored by the device manager to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

communicating from the device manager a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content, and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device;

wherein the first and second devices are devices which may be inserted into a standard tape player having a plurality of conventional user controls.

39. A device manager which is capable of transferring authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the device manager being a different device than the first and second devices, the device manager comprising:

a device manager input for receiving a transfer authorization request having an indicator of the first device, an indicator of the second device, and an indicator of the protected electronic content;

a device manager processor for updating a first device history table to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

a device manager output for communicating a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content, and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device.

40. The device manager of claim 39 wherein the device cryptographic key of the second device is a symmetric key.

41. The device manager of claim 39 wherein the device cryptographic key of the second device is a public key having a corresponding private key stored with the second device, and protecting the content cryptographic key using the device cryptographic key of the second device includes protecting the content cryptographic key with the public key such that the second device may use the corresponding private key to gain access to the content cryptographic key.

42. The device manager of claim 39 wherein the content cryptographic key is a symmetric key which is used to encrypt the protected electronic content such that only the symmetric key can be used to decrypt the content.

43. The device manager of claim 39 wherein the device manager input receives payment authorization information associated with the authorization request, and the processor charges a service fee based on the payment authorization information.

44. The device manager of claim 39 wherein the indicator of the first device in the transfer authorization request is a unique serial number.

45. The device manager of claim 39 wherein the device manager processor verifies that the first device is authorized to render the protected electronic content.

46. A device manager which is capable of transferring authorization to render protected electronic content from a first device to a second device having a device cryptographic key, the device manager being a different device than the first and second devices, the device manager comprising:

a device manager input for receiving a transfer authorization request having an indicator of the first device, an indicator of the second device and an indicator of the protected electronic content;

a device manager processor for updating a first device history table to indicate that the first device is not authorized to render the protected electronic content and updating a second device history table to indicate that second device is authorized to render the protected electronic content based on the received transfer authorization request; and

a device manager output for communicating a transfer authorization response having an indicator of the second device, an indicator of the protected electronic content and a content cryptographic key for the protected electronic content protected using the device cryptographic key of the second device so that only the second device may gain access to the content cryptographic key by use of the device cryptographic key of the second device;

wherein the first and second devices are devices which may be inserted into a standard tape player having a plurality of conventional user controls.