METHOD AND SYSTEM FOR SECURING WIRELESS COMMUNICATIONS

• US 20080123851A1
• Filed: 04/18/2007
• Published: 05/29/2008
• Est. Priority Date: 04/18/2006
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Cha, Inhyok, Guccione, Louis J., Reznik, Alexander, Racha, Renuka, Ye, Chunxuan
• Granted Patent: US 7,991,160 B2
• Time in Patent Office: Days
• US Class Current: 380/270
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 63/061 for key exchange, e.g. in peer-to-peer networks cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838
• CPC Class Codes: H04L 63/083 using passwords cryptographic mechanisms or cryptographic arrangements for entity authentication using a predetermined code H04L9/3226
• CPC Class Codes: H04L 9/0875 based on channel impulse response [CIR]
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04W 12/03 Protecting confidentiality, e.g. by encryption
• CPC Class Codes: H04W 12/041 Key generation or derivation
• CPC Class Codes: H04W 80/02 Data link layer protocols

Abstract

A wireless transmit/receive unit (WTRU) and a Node B, respectively, perform joint randomness not shared by others (JRNSO) measurement to generate JRNSO bits based on a channel estimate between the WTRU and the Node B. The WTRU and the Node B then perform a reconciliation procedure to generate a common JRNSO bits. The Node B sends the common JRNSO bits to a serving network. The WTRU and the SN secure a session key (such as an integrity key, a cipher key and an anonymity key), using the common JRNSO bits. The JRNSO measurements are performed on an on-going basis, and the session key is updated using a new set of common JRNSO bits. The JRNSO bits may be expanded by using a pseudorandom number generator (PNG) or a windowing technique. A handover may be intentionally induced to increase the JRNSO bits generation rate.

Claims

1. In a wireless communication system including a wireless transmit/receive unit (WTRU) and a serving network (SN), a method for providing secure wireless communications, the method comprising:

(a) the WTRU and a Node B performing joint randomness not shared by others (JRNSO) measurements to generate JRNSO bits based on a channel impulse response (CIR) estimate between the WTRU and the Node B;

(b) the WTRU and the Node B performing a reconciliation procedure to generate common JRNSO bits;

(c) the Node B sending the common JRNSO bits to the SN; and

(d) the WTRU and the SN securing a session key used for security using the common JRNSO bits.

2. The method of claim 1 further comprising:

the WTRU and the SN disclosing whether the WTRU and the SN have JRNSO capability wherein the JRNSO measurement are performed if both the WTRU and the SN have the JRNSO capability.

3. The method of claim 2 wherein the JRNSO capability is disclosed during a radio resource control (RRC) connection.

4. The method of claim 1 wherein the Node B reports the JRNSO bits using a power measurement message.

5. The method of claim 1 wherein the session key secured by the JRNSO bits includes at least one of an integrity key (IK), a cipher key (CK) and an anonymity key (AK).

6. The method of claim 1 wherein the channel used for the JRNSO measurements is a dedicated channel to the WTRU.

7. The method of claim 1 wherein the channel used for the JRNSO measurements is a common channel.

8. The method of claim 1 wherein the JRNSO measurement is performed while the WTRU is in one of CELL_FACH and CELL_DCH states.

9. The method of claim 1 wherein the Node B and the WTRU perform the JRNSO measurements and report the common JRNSO bits to the SN on an on-going basis.

10. The method of claim 1 further comprising:

the WTRU and the Node B repeating steps (a)-(c) to generate a new set of common JRNSO bits; and

the WTRU and the SN updating said session key using the new set of common JRNSO bits.

11. The method of claim 1 further comprising:

the WTRU and the SN updating said session key when a current key life expires.

12. The method of claim 1 wherein the WTRU and the Node B use a pseudorandom number generator (PNG) with the JRNSO bits to expand the key length.

13. The method of claim 1 wherein the WTRU and the Node B use a windowing technique such that most recently acquired random bits derived from the JRNSO measurements are pipelined with existing JRNSO bits and aging bits are discarded according to a first-in-first-out (FIFO) rule to insure that the size of the JRNSO bits meets a minimum requirement.

14. The method of claim 1 wherein the WTRU and the Node B perform the reconciliation procedure in accordance with an activation time issued by a radio network controller (RNC).

15. The method of claim 1 further comprising:

the SN sending a handover command to the WTRU and a second Node B to initiate a handover to the second Node B, the SN informing a start of JRNSO measurements between the WTRU and the second Node B;

the WTRU and the second Node B performing JRNSO measurement to generate a first set of JRNSO bits based on a channel estimate between the WTRU and the second Node B;

the WTRU and the second Node B performing a reconciliation procedure to generate a second set of common JRNSO bits;

the second Node B sending the second set of common JRNSO bits to the SN; and

the WTRU and the SN securing the session key used for security using the second set of common JRNSO bits.

16. The method of claim 1 further comprising:

the SN initiating a handover to at least one alternative Node B to generate JRNSO bits between the WTRU and said at least one alternative Node B to increase a rate of JRNSO bits generation.

17. The method of claim 16 wherein the handover is a hard handover.

18. The method of claim 16 wherein the handover is a soft handover.

19. The method of claim 18 wherein each of the Node Bs transmits the same downlink probe signal to the WTRU.

20. The method of claim 19 wherein the Node Bs sends the downlink probe signal with different time offsets.

21. The method of claim 19 wherein the WTRU uses a RAKE receiver in receiving the downlink probe signal.

22. The method of claim 16 further comprising:

the WTRU generating multiple sets of JRNSO bits associated with different Node Bs;

an accumulation controller collecting the multiple sets of JRNSO bits from the Node Bs; and

the WTRU and the accumulation controller generating a longer stream of JRNSO bits using the multiple sets of JRNSO bits.

23. The method of claim 22 wherein the WTRU and the accumulation controller accumulate each of the multiple sets of JRNSO bits until the WTRU is instructed to stop to accumulate by the accumulation controller.

24. The method of claim 22 wherein the WTRU and the Node Bs use multiple antennas in generation of the JRNSO bits.

25. The method of claim 24 wherein the WTRU and the Node Bs use multiple-input multiple-output (MIMO) in generation of the JRNSO bits.

26. The method of claim 24 wherein the WTRU and the Node Bs use beam-forming in generation of the JRNSO bits.

27. The method of claim 24 wherein the WTRU and the Node Bs adaptively changes antenna configurations for transmission and reception in generation of the JRNSO bits.

28. The method of claim 22 wherein the accumulation controller is one of the Node Bs involved in the handover.

29. The method of claim 22 wherein the accumulation controller is a radio network controller (RNC).

30. The method of claim 1 wherein the WTRU uses a downlink common pilot channel (CPICH) for JRNSO measurement.

31. The method of claim 1 wherein the Node B uses a pilot part of an uplink dedicated physical channel (DPCH) for JRNSO measurement.

32. A wireless communication system configured to secure wireless communications, the system comprising:

a wireless transmit/receive unit (WTRU) configured to perform joint randomness not shared by others (JRNSO) measurement to generate JRNSO bits based on a channel estimate between the WTRU and a Node B and perform a reconciliation procedure to generate a common JRNSO bits; and

a serving network (SN) including the Node B, the Node B configured to perform JRNSO measurement to generate JRNSO bits based on a channel estimate between the WTRU and the Node B and perform a reconciliation procedure to generate the common JRNSO bits, the SN configured to secure a session key used for security using the common JRNSO bits.

33. The system of claim 32 wherein the WTRU and the SN are configured to disclose whether the WTRU and the SN have JRNSO capability, respectively, wherein the JRNSO measurement are performed if both the WTRU and the SN have the JRNSO capability.

34. The system of claim 33 wherein the JRNSO capability is disclosed during a radio resource control (RRC) connection.

35. The system of claim 32 wherein the Node B reports the JRNSO bits using a power measurement message.

36. The system of claim 32 wherein the session key secured by the JRNSO bits includes at least one of an integrity key (IK), a cipher key (CK) and an anonymity key (AK).

37. The system of claim 32 wherein the channel used for the JRNSO measurements is a dedicated channel to the WTRU.

38. The system of claim 32 wherein the channel used for the JRNSO measurements is a common channel.

39. The system of claim 32 wherein the JRNSO measurement is performed while the WTRU is in one of CELL_FACH and CELL_DCH states.

40. The system of claim 32 wherein the Node B and the WTRU perform the JRNSO measurements and report the common JRNSO bits to the SN on an on-going basis.

41. The system of claim 32 wherein the WTRU and the Node B are configured to perform JRNSO measurement on an ongoing basis and update said at least one of the session key and the parameter using a new set of common JRNSO bits.

42. The system of claim 32 wherein the WTRU and the SN update said at least one of the session key and the parameter when a current key life expires.

43. The system of claim 32 wherein the WTRU and the Node B use a pseudorandom number generator (PNG) to generate the JRNSO bits from random bits generated from the channel estimate.

44. The system of claim 32 wherein the WTRU and the Node B use a windowing technique such that most recently acquired random bits derived from the JRNSO measurements are pipelined with existing JRNSO bits and aging bits are discarded according to a first-in-first-out (FIFO) rule to insure that the size of the JRNSO bits meets a minimum requirement.

45. The system of claim 32 further comprises:

a radio network controller (RNC) configured to issue an activation time for the reconciliation procedure, wherein the WTRU and the Node B perform the reconciliation procedure in accordance with the activation time.

46. The system of claim 32 wherein the SN is configured to send a handover command to the WTRU and a second Node B to initiate a handover to the second Node B, and inform a start of JRNSO measurements between the WTRU and the second Node B and the WTRU and the second Node B are configured to perform JRNSO measurement to generate JRNSO bits based on a channel estimate between the WTRU and the second Node B, and perform a reconciliation procedure to generate a second common JRNSO bits so that at least one of a session key and a parameter used for security is secured using the second common JRNSO bits.

47. The system of claim 32 wherein the SN is configured to initiate a handover to at least one destination Node B to generate JRNSO bits between the WTRU and said at least one destination Node B to increase a rate of JRNSO bits generation.

48. The system of claim 47 wherein the handover is a hard handover.

49. The system of claim 47 wherein the handover is a soft handover.

50. The system of claim 49 wherein each of the Node Bs transmits the same downlink probe signal to the WTRU.

51. The system of claim 50 wherein each of the Node Bs sends the downlink probe signal with different time offsets.

52. The system of claim 50 wherein the WTRU uses a RAKE receiver in receiving the downlink probe signal.

53. The system of claim 47 further comprising:

an accumulation controller configured to collect multiple sets of JRNSO bits from the Node Bs and generate a longer stream of JRNSO bits using the multiple sets of JRNSO bits, wherein the WTRU is configured to generate multiple sets of JRNSO bits associated with different Node Bs and generate a longer stream of JRNSO bits using the multiple sets of JRNSO bits.

54. The system of claim 53 wherein the WTRU and the accumulation controller accumulate each of the multiple sets of JRNSO bits until the WTRU is instructed to stop to accumulate by the accumulation controller.

55. The system of claim 54 wherein the WTRU and the Node Bs use multiple antennas in generation of the JRNSO bits.

56. The system of claim 55 wherein the WTRU and the Node Bs use multiple-input multiple-output (MIMO) in generation of the JRNSO bits.

57. The system of claim 55 wherein the WTRU and the Node Bs use beam-forming in generation of the JRNSO bits.

58. The system of claim 55 wherein the WTRU and the Node Bs adaptively changes antenna configurations for transmission and reception in generation of the JRNSO bits.

59. The system of claim 53 wherein the accumulation controller is one of the Node Bs involved in the handover.

60. The system of claim 53 wherein the accumulation controller is a radio network controller (RNC).

61. The system of claim 32 wherein the WTRU uses a downlink common pilot channel (CPICH) for JRNSO measurement.

62. The system of claim 32 wherein the Node B uses a pilot part of an uplink dedicated physical channel (DPCH) for JRNSO measurement.