One-Time Password System with Time-Based Variable Value Expiration

Solution Overview

Problem

Conventional one-time password generation methods, such as HOTP and TOTP, face issues with inconsistent effective periods due to lack of timely updates in variable values, leading to potential continuous password generation failures and increased storage needs for counter values for all users.

Innovation Solution

A user authentication system that generates a one-time password based on a seed and a variable value, records this combination with an expiration date, and updates the variable value after each use, ensuring a fixed effective period and reducing storage requirements by deleting expired values.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional one-time password generation methods (HOTP/TOTP) are used, then authentication functionality is provided, but the effective period becomes inconsistent and storage needs increase

Engineering Contradiction:

Improveauthentication reliabilityVSAvoidstorage needs for counter values

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The patent changes the parameter of variable value from a continuously incrementing counter to a time-based value with expiration. Instead of storing unlimited counter values, the system stores variable values that automatically expire after a fixed period, transforming the storage requirement from indefinite to limited.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system performs preliminary action by setting an expiration date for each variable value before it is used. This pre-established time limit ensures that the variable value will become unusable after a specific period, preventing continuous password generation failures and managing storage resources proactively.

Inventive Principle:

Principle #10Preliminary action

2Ease of operation

If variable values are not updated timely, then authentication can continue, but password generation failures occur continuously

Engineering Contradiction:

Improveauthentication continuityVSAvoidpassword generation success

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The system performs preliminary action by setting an expiration date for each variable value before it is used. This pre-established time limit ensures that the variable value will become unusable after a specific period, preventing continuous password generation failures and managing storage resources proactively.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system implements feedback by checking whether the current time exceeds the expiration date of the variable value before generating a password. This feedback mechanism ensures that only valid, non-expired variable values are used for authentication, preventing generation failures.

Inventive Principle:

Principle #23Feedback

3Adaptability or versatility

If all variable values are stored for all users, then authentication flexibility is maintained, but storage requirements increase significantly

Engineering Contradiction:

Improveauthentication flexibilityVSAvoidstorage capacity required

Core Design Contradiction:

Adaptability or versatilityVSQuantity of substance

Solution Approach 1:

The patent changes the parameter of variable value from a continuously incrementing counter to a time-based value with expiration. Instead of storing unlimited counter values, the system stores variable values that automatically expire after a fixed period, transforming the storage requirement from indefinite to limited.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system discards expired variable values automatically after their effective period ends, freeing up storage space. This discard mechanism ensures that only active, valid variable values are stored, significantly reducing the storage capacity required while maintaining authentication flexibility for current users.

Inventive Principle:

Principle #34Discarding and recovering

Data Source

PatentUS20250106029A1User authentication system capable of generating one-time password having fixed effective period, and storage medium

Publication Date: 2025.03.27 KYOCERA DOCUMENT SOLUTIONS INC

AI summary

A user authentication system includes: generating a one-time password of a user based on a seed and a variable value of the user; notifying the generated one-time password; recording the variable value in a specific area such that the variable value becomes unusable after an elapse of a specific period; and executing, when the one-time password is input, confirmation of validity of the input one-time password based on the input one-time password, the seed of the user, and the variable value of the user recorded in the specific area.