Secure telecommunications

• US 5,594,798 A
• Filed: 06/06/1995
• Issued: 01/14/1997
• Est. Priority Date: 12/09/1991
• Status: Expired due to Fees

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Cox, Richard V., Kaplan, Michael M.
• Primary Examiner(s): BARRON JR, GILBERTO
• Application Number:
  US08/468,168
• Time in Patent Office: 588 Days
• Field of Search: 380/23-25, 380/48, 380/49, 379/201, 379/442
• US Class Current: 380/257
• CPC Class Codes: H04K 1/00 Secret communication
• CPC Class Codes: H04M 2203/609 Secret communication
• CPC Class Codes: H04M 3/16 with lock-out or secrecy provision in party-line systems
• CPC Class Codes: H04M 3/42 Systems providing special services or facilities to subscribers specially adapted for wireless communication networks H04W4/00
• CPC Class Codes: H04Q 3/0016 Arrangements providing connection between exchanges

Abstract

A security node disposed in the telecommunications network connecting calling and called parties transforms information (which can be voice, data, facsimile, video and other types of calls or messages) encrypted in a first format to (a) encrypted information in a different format or to (b) non-encrypted information, and vice-versa. The node is accessible from any location connected to the network. By routing calls or messages originated by the calling party and destined for the called party via the security node, and providing appropriate control signals to the node, the information may be encrypted only over a portion of the transmission path between the parties, and clear over the remainder of the transmission path. Alternatively, the information may be encrypted in different portions of the path using different encryption algorithms. This arrangement enables the parties to obtain relatively secure communications even if only one party has a security device at the originating or terminating end, or if the parties have security devices using different handshaking protocols and encryption algorithms.

Claims

1. A method of transmitting information signals to a first device over a communications network, the information signals transmitted from a secure telephone device coupled between a telephone base and telephone microphone, the secure telephone device having a keypad, the first device having a cryptographic system, the method of comprising the steps of:

transmitting first signals to establish in the network a clear communication path between the secure telephone device and the first device;

transmitting second signals from the secure telephone device to the cryptographic system of the first device, the second signals for use in converting the clear communication path to a secure communication path;

generating information signals with use of the keypad of the secure telephone device; and

transmitting the information signals from the secure telephone device to the first device over the secure network communication path.

2. The method of claim 1 wherein the second signals comprise a signal initiating the conversion of the clear communication path to a secure communication path.

3. The method of claim 1 wherein the second signals comprise signals reflecting a cryptographic key.

4. The method of claim 1 wherein the information signals comprise user identification signals.

5. The method of claim 4 wherein the user identification signals comprise a personal identification number.

6. The method of claim 4 wherein the user identification signals comprise a social security number.

7. A method of receiving information signals by a first device, the first device having a cryptographic system, the information transmitted by a telephone having a telephone microphone and a telephone base and a secure telephone device coupled between the microphone and base, the first device coupled to the telephone by a clear communications path of a network, the method comprising the steps of:

transmitting first signals from the cryptographic system of the first device to the secure telephone device, the first signals for use in converting the clear communications path to a secure communications path; and

receiving transmitted information signals from the secure communications path, the information signals transmitted by the secure telephone device.

8. The method of claim 7 wherein the secure telephone device includes a keypad and wherein the information signals are generated with use of the keypad.

9. A method of leaving a secure message for a recipient on a voice messaging system, the message transmitted from a telephone over a communications network to the voice messaging system, the telephone including a telephone base and microphone and having a secure telephone device coupled between the base and microphone, the voice messaging system having a cryptographic system, the method comprising the steps of:

transmitting first signals from the telephone to establish in the network a clear communication path between the secure telephone device and the voice messaging system;

transmitting second signals from the secure telephone device to the cryptographic system of the voice messaging system, the second signals for use in converting the clear communication path to a secure communication path; and

transmitting a voice message from the telephone to the voice messaging system over the secure network path, the voice message for recording by the voice messaging system.

10. The method of claim 9 wherein the second signals comprise a signal initiating the conversion of the clear communication path to a secure communication path.

11. The method of claim 9 wherein the second signals comprise signals reflecting a cryptographic key.

12. A method of receiving a voice message at a voice messaging system, the voice messaging system having a cryptographic system, the voice message transmitted from a telephone having a microphone, a telephone base, and a secure telephone device coupled between the microphone and the base, the voice messaging system coupled to the telephone by a clear communications path of a network, the method comprising the steps of:

transmitting first signals for the cryptographic system of the voice messaging system to the secure telephone device, the first signals for use in converting the clear communications path to a secure communications path; and

receiving transmitted voice message signals from the secure communications path for recording by the voice messaging system, the voice message signals transmitted by the telephone.

13. A method of receiving a secure voice message from a voice messaging system, the message transmitted from the voice messaging system to a telephone over a communications network, the telephone including a telephone base and speaker and having a secure telephone device coupled between the base and speaker, the voice messaging system having an associated cryptographic system, the method comprising the steps of:

transmitting first signals from the telephone to establish in the network a clear communication path between the telephone and the voice messaging system;

transmitting second signals from the secure telephone device to the cryptographic system of the voice messaging system, the second signals for use in converting the clear communication path to a secure communication path; and

receiving at the telephone the voice message transmitted from the voice messaging system over the secure communications path.

14. The method of claim 13 wherein the second signals comprise a signal initiating the conversion of the clear communication path to a secure communication path.

15. The method of claim 13 wherein the second signals comprise signals reflecting a cryptographic key.

16. A method for secure transmission of a recorded voice message from a voice messaging system to a telephone over a communications network, the telephone including a telephone speaker and a base and having a secure telephone device coupled between the speaker and the base, the voice messaging system having a cryptographic system, the voice messaging system coupled to the telephone by a clear communications path of the network, the method comprising the steps of:

transmitting first signals from the cryptographic system of the voice messaging system to the secure telephone device, the first signals for use in converting the clear communications path to a secure communications path; and

transmitting recorded voice message signals over the secure communications path by the voice messaging system.