System, method and apparatus for secure transmission of confidential information

• US 6,396,612 B1
• Filed: 02/11/1998
• Issued: 05/28/2002
• Est. Priority Date: 02/11/1998
• Status: Expired due to Fees

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Bjorndahl, Per
• Primary Examiner(s): Pascal, Leslie
• Assistant Examiner(s): Phan, Hanh
• Application Number:
  US09/022,289
• Time in Patent Office: 1,567 Days
• Field of Search: 359/172,152,145 340/825.72,825.69,825.16
• US Class Current: 398/121
• CPC Class Codes: H04L 2209/80 Wireless
• CPC Class Codes: H04L 63/0492 by using a location-limited connection, e.g. near-field communication or limited proximity of entities
• CPC Class Codes: H04L 63/18 using different networks or channels, e.g. using out of band channels cryptographic mechanisms or cryptographic arrangements for key distribution involving distinctive intermediate devices or communication paths H04L9/0827; cryptographic mechanisms or cryptographic arrangements for authentication using a plurality of channels H04L9/3215
• CPC Class Codes: H04L 9/0838 Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these network architectures or network communication protocols for key exchange in a packet data network H04L63/061
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04L 9/14 using a plurality of keys or algorithms
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04M 1/72415 for remote control of appliances
• CPC Class Codes: H04M 1/725 Cordless telephones user interfaces specially adapted therefor H04M1/724
• CPC Class Codes: H04M 2250/02 including a Bluetooth interface

Abstract

A system, method and apparatus for establishing a secure wireless radio communications link between two devices that minimizes the exposure of sensitive information to third party interception is disclosed. The secure link is established by first establishing an infrared link between the two devices for the exchange of sensitive information, such as encryption information. Subsequent communications would then have the benefit of encryption protection, establishing the secure wireless radio communications link.

Claims

1. A private telecommunications system for secure wireless communications, said private telecommunications system comprising:

a private base station having transceiving means therein for communicating in a first and a second communication mode;

at least one mobile station, in wireless communication with said private base station, said at least one mobile station wirelessly communicating with said private base station in said first communication mode using an infrared signal and in said second communication mode using a radiofrequency signal; and

wherein, prior to communicating in said second communication mode, said at least one mobile station transmits a request message in said first communication mode to said base station to request security-related data for use in conducting said communications in said second communication mode between said at least one mobile station and said base station.

2. The private telecommunications system according to claim 1, wherein said private base station and said mobile station transceive a plurality of messages therebetween in said second communication mode, wherein, prior to transceiving a security message therebetween, said private base station and said mobile station switch transceiving to said first communication mode, and transmit said security message in said first communication mode.

3. The private telecommunications system according to claim 2, wherein said private base station and said mobile station, upon completion of the transceiving of said security message, switch transceiving therebetween to said second communication mode.

4. The private telecommunications system according to claim 2, wherein said security message comprises a plurality of encryption keys for the subsequent encryption of a plurality of said messages transceived in said second communication mode.

5. The private telecommunications system according to claim 2, wherein upon said mobile station switching said transceiving to said first communication mode, said mobile station transmits an infrared request message to said private base station.

6. The private telecommunication system according to claim 5, wherein said private base station, upon receipt of said infrared request message, transmits said security message to said mobile station.

7. The private telecommunication system according to claim 6, wherein said security message comprises a plurality of encryption keys for the subsequent encryption of a plurality of said messages transceived in said second communication mode.

8. The private telecommunication system according to claim 1, wherein said transceiving means within said private base station comprises:

infrared transceiving means for transceiving infrared signals within said mobile station in said first communications mode;

radiofrequency transceiving means for transceiving radiofrequency signals with said mobile station in said second communications mode; and

switching means for switching between said infrared and radiofrequency transceiving means.

9. The private telecommunication system according to claim 8, wherein said infrared transceiving means comprises:

a photodetector for receiving said infrared signals from said mobile station; and

an infrared emitter for transmitting said infrared signals to said mobile station.

10. The private telecommunication system according to claim 1, wherein said transceiving means within said mobile station comprises:

infrared transceiving means for transceiving said infrared signals with said private base station in said first communications mode;

radiofrequency transceiving means for transceiving said radiofrequency signals with said private base station in said second communications mode; and

switching means for switching between said infrared and radiofrequency transceiving means.

11. The private telecommunication system according to claim 10, wherein said infrared transceiving means within said mobile station comprises:

a photodetector for receiving said infrared signals from said private base station; and

an infrared emitter for transmitting said infrared signals to said private base station.

12. The private telecommunication system according to claim 1, wherein said private telecommunication system is a cordless system.

13. A method for establishing a secure communication link between a dual-mode mobile station and a dual-mode private base station of a private telecommunication system, a first mode of said dual-mode being an infrared mode and a second mode of said dual-mode being a radiofrequency mode, said method comprising the steps of:

forwarding an infrared request message from said mobile station to said base station to establish a secure communication link in said infrared mode to request security-related data for use in conducting said second communication mode between said at least one mobile station and said base station;

establishing said secure communication link between said mobile station and said private base station, said secure communication link operating in said infrared mode; and

transferring, during said secure communication link, a security message between said mobile station and said private base station in said infrared mode.

14. The method according to claim 13, wherein prior to said establishment of said secure communication link, said mobile station and said private base station operated in said radiofrequency mode.

15. The method according to claim 13, wherein, in said step of forwarding, said mobile station forwards said infrared request message to said private base station, and said private base station, upon receipt of said infrared request message, replies with an infrared reply message.

16. The method according to claim 13, wherein said security message comprises a plurality of encryption keys for the subsequent encryption of a plurality of transmissions in said radiofrequency mode.

17. The method according to claim 13, further comprising, after said step of transferring said security message, the step of:

establishing a radiofrequency communication link between said mobile station and said private base station in said radiofrequency mode.

18. The method according to claim 13, further comprising, after said step of transferring said security message, the step of:

forwarding, from said private base station, a security poll signal to said mobile station.

19. The method according to claim 18, wherein said step of forwarding said security poll signal occurs periodically.

20. The method according to claim 18, wherein said step of forwarding said security poll signal occurs randomly.

21. A mobile station for secure wireless communications in a private telecommunications system, said mobile station comprising:

radiofrequency transceiving means for transceiving a plurality of radiofrequency transmissions within said private telecommunications system;

infrared transceiving means for transceiving a plurality of infrared transmissions within said private telecommunications system; and

wherein, prior to transceiving said plurality of radiofrequency transmissions, transceiving an infrared request signal between said mobile station and a base station to request security-related data for use in encrypting said plurality of radiofrequency transmissions.

22. The mobile station according to claim 21, wherein said infrared transceiving means comprises:

a photodetector for receiving said infrared transmissions; and

an infrared emitter for transmitting said infrared transmissions.

23. The mobile station according to claim 22, wherein said infrared emitter comprises a light-emitting diode.

24. The mobile station according to claim 21, wherein said mobile station switches transceiving from said radiofrequency transceiving means to said infrared transceiving means prior to the transmission of an infrared security message within said private telecommunications system.

25. The mobile station according to claim 24, wherein, after the transmission of said infrared security message, said mobile station switches transceiving to said radiofrequency transceiving means.

26. The mobile station according to claim 24, wherein said infrared security transmission comprises a plurality of encryption keys for the subsequent encryption of a plurality of said radiofrequency transmissions between said mobile station and said private telecommunications system.

27. A private base station for secure wireless communications in a private telecommunications system, said private base station comprising:

radiofrequency transceiving means for transceiving a plurality of radiofrequency transmissions within said private telecommunications system;

infrared transceiving means for transceiving a plurality of infrared transmissions within said private telecommunications system; and

wherein prior to transceiving said plurality of radiofrequency transmissions, transceiving an infrared request signal between said base station and a mobile station to request security-related data for use in encrypting said plurality of radiofrequency transmissions.

28. The private base station according to claim 27, wherein said infrared transceiving means comprises:

a photodetector for receiving said infrared transmissions; and

an infrared emitter for transmitting said infrared transmissions.

29. The private base station according to claim 28, wherein said infrared emitter comprises a light-emitting diode.

30. The private base station according to claim 27, wherein said private base station switches transceiving from said radiofrequency transceiving means to said infrared transceiving means prior to the transmission of an infrared security message within said private telecommunications system.

31. The private base station according to claim 30, wherein, after the transmission of said infrared security message, said private base station switches transceiving to said radiofrequency transceiving means.

32. The private station according to claim 30, wherein said infrared security transmission is between said private base station and a mobile station within said private telecommunications system.

33. A method for providing secure communications between a mobile station and a base station in a private telecommunications system, comprising the steps of:

transmitting an infrared request message between said mobile station and said base station, said infrared request message transmitted in an infrared mode;

transmitting an infrared response message in said infrared mode between said mobile station and said base station in response to the infrared request message, said infrared response message including security-related data for use in connection with communications between the mobile station and the base station; and

establishing a secure communication link using the security-related data for use in communicating between the mobile station and the base station in a radiofrequency mode.

34. The method of claim 33, wherein the security-related data includes an encryption key.

35. The method of claim 34, wherein the step of establishing a secure communication link comprises the steps of:

encrypting information for transmission using the encryption key; and

transmitting the encrypted information in the radiofrequency mode.

36. The method of claim 33, wherein the infrared request message and the infrared response message are transmitted when the mobile station and the base station are within infrared communication range, and at least some communications in the radiofrequency mode on the secure communication link are conducted when the mobile station and base station are not within infrared communication range.

37. The method of claim 33, wherein the infrared request message is transmitted from the mobile station to the base station, and the infrared response message is transmitted from the base station to the mobile station.

38. The method of claim 33, wherein the infrared request message comprises a periodic infrared transmission from the base station and the infrared response message includes an encryption key and is transmitted by the mobile station.