SECURE TELEMETRIC LINK

• US 20090102682A1
• Filed: 12/22/2008
• Published: 04/23/2009
• Est. Priority Date: 08/18/2006
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: CORNDORF, ERIC D.
• Granted Patent: US 8,281,408 B2
• Time in Patent Office: Days
• US Class Current: 340/870.310
• CPC Class Codes: G06F 7/582 Pseudo-random number generators
• CPC Class Codes: H04L 2209/805 Lightweight hardware, e.g. radio-frequency identification [RFID] or sensor
• CPC Class Codes: H04L 2209/88 Medical equipments
• CPC Class Codes: H04L 9/0631 Substitution permutation network [SPN], i.e. cipher composed of a number of stages or rounds each involving linear and nonlinear transformations, e.g. AES algorithms
• CPC Class Codes: H04L 9/0637 Modes of operation, e.g. cipher block chaining [CBC], electronic codebook [ECB] or Galois/counter mode [GCM]
• CPC Class Codes: H04L 9/0844 with user authentication or key authentication, e.g. ElGamal, MTI, MQV-Menezes-Qu-Vanstone protocol or Diffie-Hellman protocols using implicitly-certified keys
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04L 9/3234 involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network H04L63/0853

Abstract

A communications protocol is used to provide data privacy, message integrity, message freshness, and user authentication to telemetric traffic, such as to and from implantable medical devices in a body area network. In certain embodiments, encryption, message integrity, and message freshness are provided through use of token-like nonces and ephemeral session-keys derived from device identification numbers and pseudorandom numbers.

Claims

1. A medical device comprising:

a transceiver module to transmit and receive information, wherein the medical device operates in a first mode that requires authentication information to permit establishing a communication session with at least one other device of a network of medical devices; and

a physical switch that, when activated, causes the medical device to operate in a second mode that does not require authentication information to permit establishing a communication session with the at least one other device of the network.

2. The device of claim 1, wherein the physical switch is activated in response to the at least one other device being located in close proximity to the medical device.

3. The device of claim 1, wherein the transceiver module initiates means of near-range telemetry upon the physical switch being activated.

4. The device of claim 3, wherein the transceiver module initiates a magnetic telemetry channel upon the physical switch being activated.

5. The device of claim 1, wherein the transceiver module renders the physical switch activatable in response to a request from the at least one other device of the network.

6. The device of claim 5, wherein the transceiver module locks the physical switch so that it is unactivatable when the physical switch is not activated within a pre-defined time-out period after the request from the at least one other device.

7. The device of claim 1, wherein the transceiver module reduces a transmission power in response to activation of the physical switch such that a transmission range in the second mode is smaller than a transmission range of the first mode.

8. The device of claim 1, further comprising a memory that stores authentication information to generate secure communications within the network of medical devices, wherein the medical device is adapted to transmit at least a portion of the authentication information to the at least one other device in response to activation of the physical switch.

9. The device of claim 1, wherein the physical switch comprises one of a magnetic switch, a Hall-effect sensor and a reed switch.

10. The device of claim 1, wherein device comprises an implantable medical device.

21. The method of claim 1, wherein the medical device comprises an implantable medical device.

11. A method comprising:

operating a medical device in a first mode that requires exchange of authentication information to permit communication with at least one other device of a network; and

in response to activation of a physical switch within the medical device, operating the medical device in a second mode that does not require exchange of authentication information to permit communication with the at least one other device of the network.

12. The method of claim 11, further comprising activating the physical switch in response to the at least one other device being located in close proximity to the medical device.

13. The method of claim 11, wherein operating the medical device in a second mode comprises initiating means of near-range telemetry in response to activation of the physical switch.

14. The method of claim 13, wherein initiating means of near-range telemetry comprises initiating a magnetic telemetry channel in response to activation of the physical switch.

15. The method of claim 11, further comprising:

receiving a request from the at least one other device to communicate with the medical device without requiring authentication; and

powering up the physical switch in response to the request from the at least one other device to render the physical switch activatable.

16. The method of claim 15, further comprising power down the physical switch to render the switch unactivatable when the physical switch is not activated within a pre-defined time-out period after the request from the at least one other device.

17. The method of claim 11, further comprising reducing a transmission power in response to activation of the physical switch such that a transmission range in the second mode is smaller than a transmission range of the first mode.

18. The method of claim 11, further comprising:

storing authentication information used in authentication; and

transmitting at least a portion of the authentication information to the at least one other device in response to activation of the physical switch.

19. The method of claim 18, further comprising establishing a authenticating the at least one other device using the authentication information transmitted to the at least other device of the network.

20. The method of claim 11, wherein the physical switch comprises one of a magnetic switch, a Hall-effect sensor and a reed switch.

22. A medical device comprising:

means for transmitting and receiving communications with at least one other device of a network; and

means for operating the medical device in a first mode that requires exchange of authentication information to permit communication with the at least one other device;

wherein the operating means operates the medical device in a second mode wherein the second mode that does not require exchange of authentication information to permit communication with the at least one other device in response to activation of a physical switch within the medical device.

23. The device of claim 22, wherein the physical switch is activated in response to the at least one other device being located in close proximity to the medical device.

24. The device of claim 22, further comprising means for initiating near-range telemetry in response to activation of the physical switch.

25. The device of claim 22, further comprising means for powering up the physical switch in response to a request from the at least one other device to render the physical switch activatable.

26. The device of claim 25, wherein the powering means power down the physical switch to render the switch unactivatable when the physical switch is not activated within a pre-defined time-out period after the request from the at least one other device.

27. The device of claim 22, further comprising means for reducing a transmission power in response to activation of the physical switch such that a transmission range in the second mode is smaller than a transmission range of the first mode.

28. The device of claim 22, further comprising:

means for storing authentication information used in authentication; and

transmitting at least a portion of the authentication information to the at least one other device in response to activation of the physical switch.

29. The device of claim 28, further comprising means for authenticating the at least one other device using the authentication information transmitted to the at least other device of the network.

30. The device of claim 22, wherein the physical switch comprises one of a magnetic switch, a Hall-effect sensor and a reed switch.

31. The device of claim 22, wherein the medical device comprises an implantable medical device.