An exhaustive survey on security and privacy issues in Healthcare 4.0 Abstract   The healthcare industry has revolutionized from 1.0 to 4.0 where Healthcare 1.0 was more doctor centric and Healthcare 2.0 replaced manual records with electronic healthcare records (EHRs). Healthcare 3.0 was patientcentric and Healthcare 4.0 uses cloud computing (CC), fog computing (FC), Internet of things (IoT), and telehealthcare technologies to share data between various stakeholders. However, framing a secure technique for Healthcare 4.0 has always been a challenging task. An insecure technique for Healthcare 4.0 may lead to the healthcare data breach where hackers can gain full access to patientsxe2x80x99 email accounts, messages, and reports. On the contrary, a secured technique for Healthcare 4.0 can provide satisfaction to all stakeholders, including patients and caregivers. Motivated from these facts, this paper presents an extensive literature review and analysis of stateoftheart proposals to maintain security and privacy in Healthcare 4.0. We also explored the blockchainbased solution to give insights to both researchers and practitioners communities. Different taxonomies used for exploring various security and privacy issues in Healthcare 4.0 are also presented in a structured manner. Then, the advantages and limitations of various security and privacy techniques are explored and discussed in the paper. Finally, existing challenges and future research directions of security and privacy in Healthcare 4.0 are presented.

Toward Secure, PrivacyPreserving, and Interoperable Medical Data Sharing via Blockchain In the era of cloud computing and big data analysis, how to efficiently share and utilize medical information scattered across various care providers has become a critical problem. This paper proposes a new framework for sharing medical data in a secure and privacypreserving way. This framework holistically integrates multiauthority attribute based encryption, blockchain and smart contract, as well as software defined networking to define and enforce sharing policies. Specifically in our framework, patientsu0027 medical records are encrypted and stored in hospital databases, where strict access controls are enforced with attribute based encryption coupled with privacy level classification. Our framework leverages blockchain technology to connect scattered private databases from participating hospitals for efficient and secure data provision, smart contracts to enable the business logic of clinical data usage, and software defined networking to revoke sharing privileges. The performance evaluation of our prototype demonstrates that the associated computation costs are reasonable in practice.