HIGH-SPEED CRYPTOGRAPHIC SYSTEM USING CHAOTIC SEQUENCES

• US 20110002460A1
• Filed: 07/01/2009
• Published: 01/06/2011
• Est. Priority Date: 07/01/2009
• Status: Active Grant

• Current Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Original Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Inventors: Michaels, Alan J., Chester, David B.
• Granted Patent: US 8,340,295 B2
• Time in Patent Office: Days
• US Class Current: 380/37
• CPC Class Codes: H04L 2209/20 Manipulating the length of blocks of bits, e.g. padding or block truncation
• CPC Class Codes: H04L 9/001 using chaotic signals
• CPC Class Codes: H04L 9/0662 with particular pseudorandom sequence generator
• CPC Class Codes: H04L 9/12 Transmitting and receiving encryption devices synchronised or initially set up in a particular manner

Abstract

A cryptographic system (500) that includes a data stream receiving device (502) configured for receiving a modified data stream representing data entries encrypted using a chaotic sequence of digits. The system also includes user processing device (503, 505) configured for receiving user access information specifying an initial value for the chaotic sequence of digits and data field location information associated with selected ones of the data entries. The system further includes a synchronized pair of chaotic sequence generators (300) coupled to the user processing devices configured for generating encryption and decryption sequences based on the initial value and the data field location information. The system additionally includes an encryption device (504) and a decryption device (506) coupled to the chaotic sequence generators and the data stream receiving device, the decrypter configured for generating an output data stream from the modified data stream by applying the decryption sequences.

Claims

1. A cryptographic system, comprising:

a data stream receiving device configured for receiving a modified data stream, said modified data stream comprising an input data stream representing a plurality of data entries encrypted using a chaotic sequence of digits;

a user processing device configured for receiving user access information, said user access information specifying an initial value for said chaotic sequence of digits and data field location information associated with selected ones of said plurality of data entries;

a chaotic sequence generator coupled to said user processing device, said chaotic sequence generator configured for generating one or more decryption sequences based on said initial value and said data field location information specified in said user access information; and

a decrypter coupled to said chaotic sequence generator and said data stream receiving device, said decrypter configured for generating an output data stream from said modified data stream by applying said decryption sequences to said modified data stream.

2. The cryptographic system of claim 1, wherein said chaotic generator generates a plurality of decryption sequences, and wherein said decrypter generates said output data stream by applying said decryption sequences to said modified data stream according to said location information.

3. The cryptographic system of claim 1, wherein said user processing device is further configured to extract said initial value and said location information specified in said user access information.

4. The cryptographic system of claim 3, wherein said extracted location information specifies one or more locations in said modified data stream associated with said selected ones of said plurality of fields.

5. The cryptographic system of claim 4, wherein each of said data field location information specifies a location of said selected ones of said plurality of entries in said modified data stream and one or more time intervals of said chaotic sequence of digits associated with said selected ones of said plurality of entries in said modified data stream.

6. The cryptographic system of claim 1, further comprising a data repository for storing said modified data stream and for sending the modified data stream to the data stream receiving device upon receipt of at least one command to access at least a portion of the plurality of data entries in said modified data stream.

7. The cryptographic system of claim 6, further comprising at least one user access terminal for generating said command.

8. A cryptographic system, comprising:

a data stream receiving device configured for receiving an input data stream comprising a plurality of data entries;

a user processing device configured for receiving user access information, said user access information specifying an initial value for generating a chaotic sequence of digits and data field location information associated with selected ones of said plurality of data entries;

a chaotic sequence generator coupled to said user processing device, said chaotic sequence generator configured for generating an encryption sequence based on said chaotic sequence of digits, said initial value, and said data field location information specified in said user access information; and

an encrypter coupled to said chaotic sequence generator and said data stream receiving device, said encrypter configured for generating a modified data stream from said input data stream by applying said encryption sequences to said input data stream.

9. The cryptographic system of claim 8, wherein said chaotic generator generates a plurality of encryption sequences, and wherein said encrypter generates said modified data stream by applying said encryption sequences to said input data stream according to said location information.

10. The cryptographic system of claim 8, wherein said user processing device is further configured to extract said initial value and said location information specified in said user access information.

11. The cryptographic system of claim 10, wherein said extracted location information specifies one or more locations in said input data stream associated with said selected ones of said plurality of fields.

12. The cryptographic system of claim 11, wherein each of said data field location information specifies a location of said selected ones of said plurality of entries in said input data stream and one or more time intervals of said chaotic sequence of digits associated with said selected ones of said plurality of entries in said input data stream.

13. The cryptographic system of claim 8, further comprising a data repository for storing said modified data stream.

14. A method for secure communications using a modified data stream, said modified data stream based on an input data stream representing a plurality of data entries and a chaotic sequence of digits having a time varying value expressed in a digital form that has no discernable regularity or order, the method comprising decrypting said modified data at a decryption device, said decrypting comprising:

receiving said modified data stream;

receiving user access information, said user access information specifying an initial value for said chaotic sequence of digits and data field location information associated with selected ones of said plurality of data entries;

generating one or more decryption sequences based on said initial value and said data field location information specified in said received user access information; and

utilizing said decryption sequences to said modified data stream to generate an output data stream from said modified data stream.

15. The method of claim 14, wherein said generating further comprises generating a plurality of decryption sequences, and wherein said utilizing further comprises applying said decryption sequences to said modified data stream according to said location information.

16. The method claim 14, prior to said generating, extracting said initial value and said data field location information from said user access information.

17. The method of claim 14, further comprising:

prior to said decrypting of said modified data stream, encrypting an input data stream at an encryption device to produce said modified data stream.

18. The method of claim 17, said encrypting further comprising:

generating said chaotic sequence of digits using said initial value;

combining or incorporating said chaotic sequence of digits with said input data stream to generate said modified data stream;

generating data location information for said plurality of entries;

receiving user information specifying said selected ones of said plurality of entries in said modified data stream to associate with said user access information; and

assembling said user key, said user parameter generator assembling said user access information utilizing said initial value, said data field location information from said encrypter, and said user information.

19. The method of claim 18, said assembling further comprising:

identifying one or more portions of said data field location information from said encrypter based on said user information;

including said identified portions of said data field location information in said user access information.

20. The method of claim 17, wherein said encrypting further comprises:

storing said modified data stream in a data repository; and

sending said modified data stream to said decryption device responsive to receipt of a command to access at least a portion of said plurality of data entries.