Adaptive Continuous Authentication System Based on the User's Emotional and Contextual State

2025;
: pp. 15 - 29
1
Lviv Polytechnic National University Department of Information Systems and Networks, Ukraine
2
Lviv Polytechnic National University Department of Information Systems and Networks, Ukraine

This article addresses the problem of low accuracy in continuous authentication systems caused by the natural variability of user behavior. An analysis of existing biometric approaches is conducted, justifying the selection of an adaptive two-stage model as an effective method for accounting for the user's psycho-emotional state. The authors designed the AURA (Automatic User Recognition Agent) system using a component-based approach, which allowed for a clear separation of the state identification and authentication tasks. A system architecture based on an ensemble of machine learning models was developed, which includes a State Probability Estimator (SPE) and a Core Authenticator (CA) that provide context-dependent verification. The proposed system demonstrated high training efficiency (91 %) and a low average Equal Error Rate (EER) across all users and states (5.7 %). These research results demonstrate the significant potential of the adaptive system to adapt to changes in user behavior and state depending on external and internal factors.

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