Decentralized Access Control and Continuous Monitoring in Healthcare Facilities: A Privacy-Preserving Framework Integrating Zero-Knowledge Proofs, Biometric Authentication, and Blockchain Technology

Abstract

Securing sensitive physical and digital areas, such as equipment rooms, medical records storage, and intensive care units (ICUs), is crucial in modern health care environments. Traditional ways of access control that depend on static authorization and centrally maintained databases are becoming more vulnerable to insider threats, identity spoofing, and data breaches. To enhance privacy, transparency and realtime threat detection in healthcare infrastructure, paper suggests a conceptual architecture for a secure, decentralized access control system that integrates blockchain technology, biometric authentication, and Zero-Knowledge Proofs (ZKPs). Recognition of fingerprints serves as the system's main authentication technique, and feature vectors are safely stored on a decentralized blockchain and cryptographically committed using Pedersen commitments. A zk-SNARK is generated during access requests to verify the accuracy of the user's biometric input without disclosing the real biometric data. Smart contracts validate access decisions, allowing for unaltered event logging and automated policy enforcement. The system combines entry-point security with Edge AI-based continuous monitoring, which tracks people's movements within the secure area using motion sensors and CCTV. The individual's continued authorization during their presence is guaranteed by periodic behavioral verification conducted by ZKPs. Anomalies that are discovered are immediately reported and stored on the blockchain for forensic examination. The approach suggested combines behavioral confirmation with physical identity verification to provide a strong multifactor authentication (MFA) framework. Although conceptual in nature, the architecture provides a scalable and privacypreserving model for next-generation healthcare access control systems because it is based on blockchain and cryptography technologies that have been proven to work.