Blockchain-Enabled EHR Sharing Framework with Dual-Protection: Integrating Attribute-Based Encryption and Hierarchical Role Access Control

The global healthcare landscape has witnessed accelerated adoption of digital transformation initiatives, with electronic health records (EHRs) emerging as the cornerstone technology for modern medical data management. While EHR systems effectively consolidate patient information and improve clinical continuity, their predominant centralised architectures create data silos that impede cross-institutional interoperability and patient sovereignty over personal health data. In this paper, we propose a blockchain-enabled EHR sharing framework that integrates attribute-based encryption with hierarchical role-based access control (RBAC) mechanisms. Our dual-protection architecture combines 1) an attribute-oriented privacy preservation scheme that ensures data immutability and fine-grained access through cryptographic proofs, with 2) a multi-level role hierarchy system that enables efficient permission management among healthcare stakeholders. By establishing dynamic mappings between user attributes and institutional roles, we achieve secure yet flexible authorization processes without compromising system performance. Experimental evaluations demonstrate superior performance metrics in cryptographic operations and access verification latency, validating the practicality of the framework for real-world EHR exchange scenarios.