Dynamic signature generation from keystroke dynamics

Patent metadata

Field	Value
Publication number	US-10693661-B1
Application number	US-201715801646-A
Country	US
Kind code	B1
Filing date	Nov 2, 2017
Priority date	Jan 11, 2017
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

Described herein are various technologies pertaining to extracting cryptographic keys from user behavioral biometrics, specifically keystroke dynamics. Such cryptographic keys can be used for, among other things, user authentication throughout computer sessions. Keystroke dynamics are timing data indicating when keys were pressed and when they were released.

First claim

What is claimed is:

1. A system that is configured to authenticate a user of a computing device as the user is typing on a keyboard, the system comprising:
a processor; and
memory that stores instructions that, when executed by the processor, cause the processor to perform acts comprising:
constructing an observed signature for the user based upon a first amount of time taken by the user to complete a keystroke pattern, the first amount of time measured as at least one keystroke associated with the keystroke pattern is set forth by the user as the user is typing on the keyboard, wherein constructing the observed signature comprises:
constructing a bitstream that comprises a bit value that is assigned to the keystroke pattern, wherein the bit value indicates whether the first amount of time taken by the user to complete the keystroke pattern is greater than an average amount of time taken by multiple users to complete the keystroke pattern;
generating a cryptographic key based upon the bitstream; and
generating the observed signature based upon the cryptographic key;

comparing the observed signature for the user with an authentication signature for the user, the authentication signature previously constructed based upon a second amount of time previously taken by the user to complete the keystroke pattern, the second amount of time measured when the user previously typed on the keyboard; and
authenticating the user of the computing device based upon the comparing of the observed signature of the user with the authentication signature for the user such that the computing device continues to permit the user to control at least one operation of the computing device.

2. The system of claim 1 , the acts further comprising:
receiving a username and password for the user;
authenticating the user for a computing session based upon the username and password, wherein the observed signature is constructed during the computing session subsequent to the user being authenticated based upon the username and password.

3. The system of claim 1 , wherein the keystroke pattern includes a press of a first key followed by a press of a second key, and the first amount of time is a time between the press of the first key and the press of the second key, wherein no other keys were pressed between when the first key and the second key were pressed.

4. The system of claim 1 , wherein the keystroke pattern includes a release of a first key followed by a release of a second key, and the first amount of time is a time between the release of the first key and the release of the second key, wherein no other keys were pressed between when the first key and the second key were pressed.

5. The system of claim 1 , wherein the keystroke pattern includes a press of a first key followed by a release of a second key, and the first amount of time is a time between the press of the first key and the release of the second key, wherein no other keys were pressed between when the first key and the second key were pressed.

6. The system of claim 1 , wherein the keystroke pattern includes a release of a first key followed by a press of a second key, and the first amount of time is a time between the release of the first key and the press of the second key, wherein no other keys were pressed between when the first key and the second key were pressed.

7. The system of claim 1 , wherein the bitstream comprises multiple bits that are respectively assigned to different keystroke patterns.

8. The system of claim 1 , wherein constructing the observed signature comprises using fuzzy extraction on the bitstream to construct the observed signature.

9. A method, comprising:
during a first computing session of a user with a computing device, constructing an observed signature for the user based upon a first amount of time taken by the user to complete a predefined keystroke pattern as the user is typing on a keyboard, wherein constructing the observed signature for the user comprises:
constructing a bitstream that includes a bit value that is assigned to the predefined keyboard pattern, wherein the bit value indicates whether the first amount of time taken by the user to complete the predefined keystroke pattern is greater than an average amount of time taken by a set of users in a population to complete the predefined keystroke pattern;
generating a cryptographic key based upon the bitstream; and
generating the observed signature based upon the cryptographic key;

comparing the observed signature for the user with an authentication signature for the user, the authentication signature previously constructed based upon a second amount of time taken by the user to complete the predefined keystroke pattern, the second amount of time captured when the user previously typed on the keyboard during a second computing session that is different from the first computing session; and
authenticating the user of the computing device based upon the comparing of the observed signature of the user with the authentication signature for the user, wherein the computing device continues to permit the user to control at least one operation of the computing device based upon the authenticating of the user of the computing device.

10. The method of claim 9 , further comprising:
receiving a username and password for the user;
authenticating the user for a computing session based upon the username and password, wherein the observed signature is constructed during the first computing session subsequent to the user being authenticated based upon the username and password.

11. The method of claim 9 , wherein the keystroke pattern is a press of a first key followed by a press of a second key, and the first amount of time is a time between the press of the first key and the press of the second key, wherein no other keys were pressed between when the first key and the second key were pressed.

12. The method of claim 9 , wherein the keystroke pattern is a release of a first key followed by a release of a second key, and the first amount of time is a time between the release of the first key and the release of the second key, wherein no other keys were pressed between when the first key and the second key were pressed.

13. The method of claim 9 , wherein the keystroke pattern is a press of a first key followed by a release of a second key, and the first amount of time is a time between the press of the first key and the release of the second key, wherein no other keys were pressed between when the first key and the second key were pressed.

14. The method of claim 9 , wherein the keystroke pattern is a press of a key followed by a release of the key, and the first amount of time is a time between the press of the key and the release of the key, wherein no other keys were pressed between when the key was pressed and released.

15. The method of claim 9 , wherein the bitstream comprises multiple bits that are respectively assigned to different keystroke patterns.

16. The method of claim 15 , wherein constructing the observed signature comprises using fuzzy extraction on the bitstream to construct the observed signature.

17. A computer-readable storage medium comprising instructions that, when executed by a processor, cause the processor to perform acts comprising:
during a first computing session of a user with a computing device, constructing an observed signature for the user based upon a first amount of time taken by the user to complete a predefined keystroke pattern as the user is pressing keys on a keyboard, wherein constructing the observed signature c

Assignees

• Nat Tech & Eng Solutions Sandia Llc

Inventors

• Hamlet Jason

Classifications

• H04L2209/34

  Encoding or coding, e.g. Huffman coding or error correction · CPC title

• H04L9/3226

  using a predetermined code, e.g. password, passphrase or PIN (network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L63/083) · CPC title

• H04L9/0866

  involving user or device identifiers, e.g. serial number, physical or biometrical information, DNA, hand-signature or measurable physical characteristics · CPC title

• G06F21/316 Primary

  by observing the pattern of computer usage, e.g. typical user behaviour · CPC title

• H04L9/3247 Primary

  involving digital signatures · CPC title