An Efficient Blockchain Based Data Access with Modified Hierarchical Attribute Access Structure with CP-ABE Using ECC Scheme for Patient Health Record

Secure patient health record (PHR) information exchange via cloud computing is a considerable security risk to user privacy. The fundamental reason of this issue is cloud computing’s reliance on trustworthy third parties to share data across it. To exchange data securely, many conventional cryptographic algorithms employ various keying approaches. However, relying on a trusted third party compromises the privacy of consumers’ data. To offer secure communication without the involvement of a third party, a distributed blockchain based (DBC) ciphertext–policy attribute-based encryption (CP-ABE) approach is employed in this study. Because of bilinear paring and simple scalar multiplication factors, the proposed CP-ABE system is entirely dependent on elliptic curve cryptography to reduce complexity. Furthermore, the data requester provides dynamic attributes, and a user-centric access policy is created, allowing multiple authorities to manage the attributes and provide data access. Data confidentiality, data authentication, user authentication, and tamper-proof data are all guaranteed by the suggested method. The DBC-CP-ABE method is used to provide user-centric access policies and effective key management.