A blockchain-based multi-authority hierarchical attribute encrypted data sharing scheme in the Internet of Medical...

Area of Science:

• Cybersecurity
• Health Informatics
• Distributed Systems

Background:

• The Internet of Medical Things (IoMT) generates vast sensitive data, posing security challenges.
• Existing Ciphertext-Policy Attribute-Based Encryption (CP-ABE) schemes lack data source authentication and face single-point-of-failure risks.
• Hierarchical data management in IoMT requires robust and efficient encryption solutions.

Purpose of the Study:

• To propose a blockchain-based multi-authority hierarchical attribute-based encryption scheme for IoMT.
• To address limitations of existing CP-ABE schemes, including data source authentication and failure risks.
• To enhance secure and efficient sharing of sensitive medical data.

Main Methods:

• Integration of a Distributed Key Generation (DKG) protocol with threshold BLS signatures for collaborative authentication.
• Implementation of a dynamic update mechanism for secure collaborative key management.
• Optimization of encryption logic using hierarchical access trees, multi-authority collaboration, and proxy re-encryption (PRE) for efficient revocation.

Main Results:

• The scheme provides resistance to chosen-plaintext attacks (IND-CPA) and collusion attacks.
• The DKG protocol is proven valid, robust, confidential, and Sybil attack-resistant.
• Performance evaluation shows lower computational and storage overhead compared to existing solutions, with practical latency in large-scale tests.

Conclusions:

• The proposed blockchain-based CP-ABE scheme offers enhanced security and efficiency for IoMT data sharing.
• The system demonstrates feasibility for real-world IoMT applications with resource constraints and real-time needs.
• This approach effectively tackles data source authentication, hierarchical data management, and user revocation challenges.