# US 2021/0240809 A1 · Electronic signature authentication system

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2021/0240809 A1
- Document ID: US20210240809A1
- Status: Published application
- Kind: A1
- Application number: 17/236,102
- Filed: 2021-04-21
- Published: 2021-08-05
- Earliest claimed: 2019-03-05
- Assignees: King Abdulaziz University
- Applicants: King Abdulaziz University
- Inventors: Fahad ALSOLAMI
- Web page: https://patentgrep.com/patent/US20210240809A1

## CPC

- G06F 21/32: using biometric data, e.g. fingerprints, iris scans or voiceprints
- G06F 21/40: by quorum, i.e. whereby two or more security principals are required
- G06F 21/602: {Providing cryptographic facilities or services}
- G06V 40/1353: {Extracting features related to minutiae or pores}
- G06V 40/1371: {Matching features related to minutiae or pores}
- H04L 9/085: {Secret sharing or secret splitting, e.g. threshold schemes}
- H04L 9/0861: {Generation of secret information including derivation or calculation of cryptographic keys or passwords}
- H04L 9/3226: {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)}
- H04L 9/3231: {Biological data, e.g. fingerprint, voice or retina (network architectures or network communication protocols for supporting authentication of entities using biometrical features in a packet data network H04L63/0861)}
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)
- G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)

## Abstract

A system and methods for authenticating an electronic signature using a biometric fingerprint includes registering a subscriber to the service. The subscriber asks document signers enter their fingerprint(s) by a fingerprint reader. The fingerprint data is applied to a fingerprint matcher which generates a gallery pair table of fingerprint minutiae for each signer. A secret user ID or operation number is generated. A sharing module splits the fingerprint information into N shares and generates a threshold number S. The secret is applied to the sharing module and N shares of the secret are generated. The N shares of fingerprint data are each combined with one share the secret to form N combined shares. The N combined shares are each stored in different cloud storage locations. Retrieval of the secret to authenticate the signers requires S signers to enter their fingerprints and S combined shares to be downloaded from the clouds.

## Claims

### Claim 1

An electronic signature authentication system, comprising:
a fingerprint reader configured to read a fingerprint on a touchscreen and/or measure depth characteristics of the fingerprint by multispectral imaging;
a controller;
a processor connected to the controller;
a transceiver;
a memory storing program instructions;
a database;
a fingerprint matcher connected to the processor, wherein the fingerprint matcher has program instructions for extracting fingerprint minutiae and constructing a gallery pair table and a probe pair table of the fingerprint minutia minutiae;
a secret module for generating a secret;
a sharing module connected to the processor,
wherein the sharing module has program instructions for splitting data into N shares and assigning a threshold number S of shares needed to retrieve the data, where N≥2S−1, where N and S are integers greater than 1, and where N is the number of minutiae pairs,
wherein the sharing module has program instructions configured to run a secret sharing scheme algorithm, and
wherein the secret sharing algorithm generates N shares by choosing a polynomial f(x) such that f(x)=a0+a1x+ . . . ak−1xs−1; setting a0 equal to the secret;
evaluating N1=f(1), . . . , Ni=f(i), . . . , Nn=f(n), for i=1, . . . , n is an integer, wherein the set of {N1, N2, . . . , Nn} are the N generated shares and s represents the number of shares needed to retrieve the secret and a1-ak−1 are randomly selected coefficients;
wherein the controller has circuitry configured to
receive a subscriber request to record a fingerprint,
cause the fingerprint reader to record fingerprint data,
cause the secret module to generate the secret,
instruct the processor to
apply the fingerprint data to the fingerprint matcher,
apply the fingerprint minutiae to the sharing module to generate N
fingerprint minutiae shares and the threshold number S,
apply the secret to the sharing module to generate N shares of the secret,
combine the N shares of the fingerprint minutiae shares and the N shares of the secret to generate N combined shares; and
wherein the controller further has circuitry configured to cause the transceiver to transmit each share of the N combined shares to a unique cloud storage location of a plurality of cloud storage locations.

### Claim 2 (depends on 1)

The system of claim 1, wherein the controller further has circuitry configured to
receive registration information from a user requesting access to the system;
record the registration information in the database;
request a password from the user;
store the password of the user with the registration information in the database; and
register the user as a subscriber of the system.

### Claim 3

(canceled)

### Claim 4

(canceled)

### Claim 5 (depends on 2)

The system of claim 2, wherein the subscriber enters the password to access the system.

### Claim 6 (depends on 2)

The system of claim 2, further comprising
a second factor authentication module connected to the controller, wherein the second factor authentication module has circuitry configured to generate a verification number;
wherein the controller has circuitry configured to cause the transceiver to transmit the verification number to a personal computing device of the subscriber with a request for the subscriber to enter the verification number on the personal computing device;
wherein the controller has circuitry configured to receive the entered verification number as a second authentication of the electronic signature.

### Claim at position 7

7-20. (canceled)