A blockchain-based verifiable CP-ABE scheme for medical data privacy protection

Area of Science:

• Computer Science
• Information Security
• Healthcare Informatics

Background:

• Cloud-based Electronic Health Record (EHR) sharing faces significant security challenges, including single points of failure and privilege abuse.
• Existing methods struggle with validating data and access policy integrity during transit and storage.

Purpose of the Study:

• To propose a novel scheme for secure EHR sharing in the cloud by integrating blockchain with verifiable ciphertext policy attribute-based encryption (CP-ABE).
• To address the limitations of centralized privilege management and enhance data integrity and access policy validation.

Main Methods:

• Decentralizing policy verification across multiple blockchain nodes to eliminate single points of failure and improve robustness.
• Utilizing Vector Commitment technology to bind access policies to ciphertext, enabling rapid tamper detection and policy authenticity.
• Integrating Attribute-Based Proxy Re-Encryption (AB-PRE) for dynamic and efficient access right adjustments.

Main Results:

• The proposed scheme effectively decentralizes policy verification, enhancing system robustness.
• Vector Commitment ensures rapid detection of policy tampering and guarantees policy authenticity.
• AB-PRE facilitates dynamic access control based on patient needs and status.

Conclusions:

• The integrated blockchain and CP-ABE scheme offers an efficient and effective solution for secure cloud-based EHR sharing.
• The approach enhances data integrity, access control, and system resilience against failures and attacks.