METHODS FOR THE GENERATION OF IDENTICAL SYMMETRICAL CRYPTOGRAPHIC KEYS

• US 20090046859A1
• Filed: 02/14/2008
• Published: 02/19/2009
• Est. Priority Date: 08/17/2007
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Stromberg, Guido, Krogmann, Martin, Bichler, Daniel, Loew, Manuel, Lentsch, Thomas, Barisic, Daniel
• Granted Patent: US 8,363,838 B2
• Time in Patent Office: Days
• US Class Current: 380/259
• CPC Class Codes: H04L 2209/805 Lightweight hardware, e.g. radio-frequency identification [RFID] or sensor
• CPC Class Codes: H04L 9/0872 using geo-location information, e.g. location data, time, relative position or proximity to other entities

Abstract

Methods and algorithms for generating identical symmetrical cryptographic keys. In a method for generating a symmetrical cryptographic key, a first profile is generated, the first profile comprising a series of data points collected over a first period of time. A start time of the first profile is identified and the first profile divided into a sequence of time-based segments, each time-based segment comprising at least one data point. A first symmetrical cryptographic key is calculated from the sequence of time-based segments, and the first symmetrical cryptographic key is stored for at least one of encrypting and decrypting data in cooperation with a second symmetrical cryptographic key substantially identical to the first symmetrical cryptographic key.

Claims

1. A method for generating a symmetrical cryptographic key comprising the steps of:

generating a first profile, the first profile comprising a series of data points collected over a first period of time;

identifying a start time of the first profile and dividing the first profile into a sequence of time-based segments, each time-based segment comprising at least one data point;

calculating a first symmetrical cryptographic key from the sequence of time-based segments; and

storing the first symmetrical cryptographic key for at least one of encrypting and decrypting data in cooperation with a second symmetrical cryptographic key substantially identical to the first symmetrical cryptographic key.

2. The method of claim 1, further comprising the steps of:

generating a second profile, the second profile comprising a series of data points collected over a second period of time substantially the same as the first period of time;

identifying a start time of the second profile in common with the start time of the first profile and dividing the second profile into a sequence of time-based segments, each time-based segment comprising at least one data point;

calculating the second symmetrical cryptographic key from the sequence of time-based segments of the second profile; and

storing the second symmetrical cryptographic key for at least one of encrypting and decrypting data in cooperation with the first symmetrical cryptographic key.

3. The method of claim 2, wherein

the step of generating a first profile further comprises generating an acceleration profile by a sensor in a first device;

and

the step of generating a second profile further comprises generating an acceleration profile by a sensor in a second device.

4. The method of claim 3, further comprising the step of removably coupling the first device and the second device before the steps of generating a first profile and generating a second profile.

5. The method of claim 3, wherein

the step of generating a first profile further comprises generating the acceleration profile by a three-dimensional acceleration sensor integrated with a transceiver of the first device;

and

the step of generating a second profile further comprises generating the acceleration profile by a three-dimensional acceleration sensor integrated with a transceiver of the second device.

6. The method of claim 2, further comprising the steps of:

encrypting data in a first device with the first symmetrical cryptographic key;

transmitting the encrypted data by the first device;

receiving the encrypted data by a second device having the second symmetrical cryptographic key; and

decrypting the encrypted data in the second device with the second symmetrical cryptographic key.

7. The method of claim 2, wherein the step of calculating the second symmetrical cryptographic key further comprises the steps of:

comparing the time-based segments with sample data;

producing at least one weight factor for each time-based segment;

combining similar weight factors across the second profile into at least two groups;

assigning a number to each of the groups; and

creating the second symmetrical cryptographic key from the number assigned to each of the groups.

8. The method of claim 1, wherein the step of calculating a first symmetrical cryptographic key further comprises the steps of:

comparing the time-based segments with sample data;

producing at least one weight factor for each time-based segment;

combining similar weight factors across the first profile into at least two groups;

assigning a number to each of the groups; and

creating the first symmetrical cryptographic key from the number assigned to each of the groups.

9. A method for exchanging cryptographically encoded data comprising the steps of:

obtaining a data profile by a sensing element integrated with a transceiver in each of a plurality of devices;

calculating an identical symmetrical cryptographic key from the data profile by the transceiver in each of the plurality of devices; and

using the identical symmetrical cryptographic key to encrypt and decrypt data in the transceiver in each of the plurality of devices, in communications among the plurality of devices.

10. The method of claim 9, wherein the step of calculating an identical symmetrical cryptographic key comprises:

dividing the data profile into a plurality of segments;

determining a plurality of weight factors, one for each of the plurality of segments, by comparing the plurality of segments with at least one sample;

providing the plurality of weight factors to a hash function;

combining the plurality of weight factors into a plurality of groups;

assigning a number to each of the plurality of groups; and

creating the identical symmetrical cryptographic key from the number assigned to each of the plurality of groups.

11. The method of claim 9, wherein the step of obtaining a data profile comprises:

applying a common physical stimulus to the plurality of devices; and

creating a data profile by the sensing element in each of the plurality of devices based at least in part on the common physical stimulus.

12. The method of claim 11, further comprising the step of removably coupling the plurality of devices.

13. The method of claim 11, wherein the step of applying a common physical stimulus further comprises shaking the plurality of devices, and wherein the step of creating a data profile further comprises creating a three-dimensional acceleration profile.

14. The method of claim 11, wherein the step of applying a common physical stimulus further comprises operating a vehicle to which the plurality of devices is related.

15. The method of claim 14, wherein the step of creating a data profile further comprises creating an acceleration profile.

16. The method of claim 11, wherein the step of creating a data profile further comprises creating an acoustic profile.

17. A method for generating a symmetrical cryptographic key comprising the steps of:

generating a first profile, the first profile comprising a series of data points collected over a first period of time;

dividing the first profile into a plurality of time-based segments, each time-based segment comprising at least one data point;

calculating a first symmetrical cryptographic key from at least a portion of the plurality of time-based segments, and

storing the first symmetrical cryptographic key for at least one of encrypting and decrypting data in cooperation with a second symmetrical cryptographic key substantially identical to the first symmetrical cryptographic key.

18. The method of claim 17, further comprising the steps of:

generating a second profile, the second profile comprising a series of data points collected over a second period of time substantially the same as the first period of time;

dividing the second profile into a plurality of time-based segments, each time-based segment comprising at least one data point;

calculating the second symmetrical cryptographic key from a least a portion of the plurality of time-based segments of the second profile; and

storing the second symmetrical cryptographic key for at least one of encrypting and decrypting data in cooperation with the first symmetrical cryptographic key.

19. The method of claim 18, further comprising the steps of:

identifying a start time of the first period of time; and

identifying a start time of the second period of time, the start time of the second period of time substantially the same as the start time of the first period of time.

20. The method of claim 18, further comprising the steps of:

encrypting data in a first device with the first symmetrical cryptographic key;

transmitting the encrypted data by the first device;

receiving the encrypted data by a second device having the second symmetrical cryptographic key; and

decrypting the encrypted data in the second device with the second symmetrical cryptographic key.

21. An algorithm for encrypting and decrypting data communications, the algorithm executed within each of at least two communication devices and comprising the steps of:

creating a data profile from a physical input during a period of time;

identifying a start time of the period of time and segmenting the data profile into a plurality of time-based segments;

creating a first cryptographic key from the plurality of time-based segments;

storing the first cryptographic key in a first communication device;

encrypting data in the first communication device using the first cryptographic key;

transmitting the encrypted data to a second communication device; and

decrypting the encrypted data in the second communication device using a second cryptographic key substantially identical to the first cryptographic key.

22. The algorithm of claim 21, wherein the step of creating a first cryptographic key comprises the steps of:

determining a plurality of weight factors by comparing the plurality of segments with at least one sample;

providing the plurality of weight factors to a hash function;

combining the plurality of weight factors into a plurality of groups; and

assigning a number to each of the plurality of groups.

23. The algorithm of claim 21, wherein the step of creating a data profile further comprises creating a three-dimensional data profile.

24. An algorithm for encrypting and decrypting data communications, the algorithm executed within a transceiver and comprising the steps of:

creating, by a sensor integrated with the transceiver, a data profile from a physical input;

segmenting the data profile into a plurality of segments;

determining a plurality of weight factors, one for each of the plurality of segments, by comparing the plurality of segments with at least one sample;

providing the plurality of weight factors to a hash function executed within the transceiver;

combining the plurality of weight factors into a plurality of groups;

assigning a number to each of the plurality of groups;

creating a cryptographic key from the number assigned to each of the plurality of groups; and

encrypting data by the transceiver using the cryptographic key.

25. The algorithm of claim 24, further comprising the step of decrypting data by the transceiver using the cryptographic key, wherein the data decrypted has been encrypted and transmitted by a second transceiver having an identical cryptographic key created according to the algorithm.