## 4 Related Work
### Security and Privacy-Related Solutions of HIS  
Although no two healthcare organizations are the same, many face comparable difficulties regarding data security that result from conflicting desires faced by every modern company: innovation and expansion versus compliance and legal risk mitigation; according to the research, the following five health information system challenges must be resolved [95]:  
* The conflict between data expansion and analytics, and data minimization. * Dealing with mobile applications and related devices. * Creating adequate cross-functional privacy and security teams. * The effects of acquisitions on data. * Effective and tier-based vendor management. EHRs are replacing paper-based medical records in many hospitals. Higher patient care is now possible due to specialized software and electronic diagnostic equipment. The shift to electronic-based systems allows clinicians to use streamlined, automated processes and customized applications to aid in patient diagnosis and treatment. However, introducing these technologies increases the privacy hazards associated with patient data. When numerous patient records are available electronically, a hostile person attempting to compromise them will be able to readily acquire enormous volumes of data. Some of the most prevalent technological security flaws faced by most healthcare-related firms are as follows [95]:  
* Security and privacy policies and plans that are either inadequate or non-existent. * Continuous security, privacy, and compliance reviews are lacking. * No backup encryption method is in place. * The passwords for the operating system, applications, and databases are weak. * Filtering of material and audit tracking are both lacking. * Inadequate malware protection exists for viruses, Trojans, spyware, and rootkits. * Personal health information is disclosed. * Accountability and duty are lacking. Some of the current health records management systems are costly, complex, and prone to human error [96]. The researchers proposed the Medicalchain project, which uses the blockchain to manage the health records of registered patients, noting the inability to implement the solution on the SSN system, the Italian National Health Service. A solution envisioned by researchers for healthcare provision in Europe enables sharing of health records, secure integration using blockchain and scalable data lakes, and ensures secure access to data [97]. They have proposed the Serums Smart Health Center System (SHCS) using Hyperledger Fabric and individual data lakes and built a model of access-control model to support collective and individual rules. [PERSON] and others [18] proposed a permissioned blockchain-based system for EHR data sharing and integration and developed the ACTION-EHR system for patient-centric reasons. They presented a framework for the specific data sharing for radiation oncology and granular access control. [PERSON] and others [98] proposed patient-centric healthcare data management (PCHDM) using blockchain. However, they used static access control, so it cannot monitor the healthcare record continuously, which is different from our proposed solution of using a usage control module. Concerns about patient data privacy and security have led to a low adoption rate of EHRs by several healthcare facilities. Furthermore, EHR research faces difficulties in securing a large amount of sensitive health data in multiple places, and formats [94]. The literature review showed that technical and legal factors, individuals' right to privacy, and policy making are the main challenges facing the development of EHR systems in low- and middle-income countries [99]. However, most of the previous literature only elucidated these problems without reviewing the practical solutions that can be adopted to address them. Despite the importance of BT in improving security and privacy in network systems, including healthcare systems, this field requires more research and development.