Blockchain-Based Multi-Factor Access Control for Preserving Privacy in Cloud Storage of Medical Records

In recent days, increasing healthcare data stored in the cloud has raised serious concerns over securing sensitive medical images and records. Traditional approaches for preserving privacy in cloud environments had faced challenges like data breaches, unauthorized access, inefficient encryption and lack of transparent access control. Therefore, this research proposes Blockchain-Based Multi-Factor Access Control (BBMFAC) for privacy preservation for healthcare data in cloud environments. Initially, patient healthcare data like Computed Tomography (CT) images and medical records is collected and preprocessed. Then, CT images are encrypted and confidential textual data is securely embedded within these images. After that, encrypted data is uploaded to cloud by InterPlanetary File System (IPFS) which generates unique hashes that stored on private blockchain. Next, data access is controlled by utilizing the proposed BBMFAC where smart contracts impose role-based permissions and multi-factor authentication ensures secure user verification. Finally, authorized users retrieve and decrypt the data, with key correlation performed by the Gaussian Regression Algorithm (GRA) which ensures accurate matching of access credentials and secure data recovery. The proposed BBMFAC has achieved better results in terms of accuracy of 94% and Mean Square Error (MSE) of 0.0010 when compared with existing Customizable Unique Node Access (CUNA) respectively.