Encryption STE communications through private branch exchange (PBX)

• US 20050210235A1
• Filed: 12/10/2004
• Published: 09/22/2005
• Est. Priority Date: 03/17/2004
• Status: Active Grant

• Current Assignee: TeleCommunication Systems Inc (Comtech Telecommunications Corporation)
• Original Assignee: TeleCommunication Systems Inc (Comtech Telecommunications Corporation)
• Inventors: Reed, Eric, Best, Fiona S., McClintock, Dorothy A., Hartwell, Wesley R., Lee, William Jeremy
• Granted Patent: US 8,489,874 B2
• Time in Patent Office: Days
• US Class Current: 713/151
• CPC Class Codes: H04L 2209/80 Wireless
• CPC Class Codes: H04L 9/00 Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols

Abstract

A reach back secure communications terminal includes a digital PBX adapter that offers immediate and secure voice, data and video connectivity over any of various commercially available PBX systems. In addition to use with a PBX system, integrated components simplify access to varied networks allowing deployed users to select and connect quickly to a network that best supports their present mission. Commercial or optional NSA Type 1 encryption may be implemented. Networking options include any of PSTN, PBX, GSM (or CDMA or other cell telephone standard), SAT, IP and WiFi. The digital PBX adapter includes an audio mixer that converts a 4-wire input from a handset jack of a PBX handset base, into a 2-wire output destined for an encryption unit (FNBDT). The user determines a necessary gain of the audio mixer for the particular PBX system by trial and error using a multi-position switch.

Claims

1. A reach-back communications terminal, comprising:

an FNBDT encryption device; and

an audio mixer between an input from a PBX handset base and said FNBDT encryption device, said audio mixer converting a 4-wire input from said PBX handset base into a 2-wire output destined for said FNBDT encryption device.

2. The reach-back communications terminal according to claim 1, further comprising:

a gain control switch to set a gain of said audio mixer.

3. The reach-back communications terminal according to claim 2, wherein:

said gain control switch has at least 4 positions corresponding to at least 4 gain seen in said 2-wire output of said audio mixer.

4. The reach-back communications terminal according to claim 1, further comprising:

a connection for a handset disconnected from said PBX handset base; and

a switchable bypass path between said input from said PBX handset base and said connection for said handset, allowing otherwise normal operation of said handset with said PBX handset base.

5. A method of allowing encrypted communications over an unsecure private branch exchange (PBX) system, comprising:

disconnecting a handset from a PBX handset base unit;

connecting a 4-wire input to an audio mixer to a handset jack on said PBX handset base unit vacated by said handset; and

connecting an encryption unit to a 2-wire output of said audio mixer.

6. The method of allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 5, wherein:

said encryption unit includes a secure handset.

7. The method of allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 5, further comprising:

setting a gain of said audio mixer to a position which allows establishment of communications through said encryption unit.

8. The method of allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 7, wherein:

said gain of said audio mixer is set by a multi-position switch.

9. The method of allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 8, wherein:

said multi-position switch is a multi-position slide switch.

10. The method of allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 9, wherein:

said multi-position slide switch has at least 4 positions, each of said 4 positions causing a different, pre-determined gain in said audio mixer.

11. The method of allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 5, wherein:

said encryption unit is an FNBDT device.

12. The method of allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 5, further comprising:

connecting said handset to a bypass path from said audio mixer allowing use of said handset with said PBX handset base unit.

13. Apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system, comprising:

means for disconnecting a handset from a PBX handset base unit;

means for connecting a 4-wire input to an audio mixer to a handset jack on said PBX handset base unit vacated by said handset; and

means for connecting a encryption unit to a 2-wire output of said audio mixer.

14. The apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 13, wherein:

said encryption unit includes a secure handset.

15. The apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 13, further comprising:

means for setting a gain of said audio mixer to a position which allows establishment of communications through said encryption unit.

16. The apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 15, wherein:

said gain of said audio mixer is set by a multi-position switch.

17. The apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 16, wherein:

said multi-position switch is a multi-position slide switch.

18. The apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 17, wherein:

said multi-position slide switch has at least 4 positions, each of said 4 positions causing a different, pre-determined gain in said audio mixer.

19. The apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 13, wherein:

said encryption unit is an FNBDT.

20. The apparatus for allowing encrypted communications over an unsecure private branch exchange (PBX) system according to claim 13, further comprising:

means for connecting said handset to a bypass path from said audio mixer allowing use of said handset with said PBX handset base unit.