Page 39 - AIH-1-2
P. 39

Artificial Intelligence in Health                                        Blockchain for health-care security



            the blockchain supply. This protects patient data integrity   4.4. PBFT
            and increases the resilience of PoS-based health-care   PBFT can solve the byzantine problem, as presented
            blockchains  against  threats.  For  health-care  applications   in a published paper.  A byzantine fault is a defective
                                                                                 30
            based on blockchain, switching from complicated    algorithm. Byzantine fault tolerance can ensure the safety
            computational problems to POS results in lower energy   and efficiency of the system so that hardly [(n-1)/  duplicate
                                                                                                     3
            consumption and enables randomized validator selection,   data are defective over the system in a lifetime. In medical
            node participation incentives, performance-based rewards,   science, PBFT algorithms create an efficient impact
            and continuous work to resolve distribution issues.    because several nodes are being shared and maintained by
                                                         36
            The security, effectiveness, and dependability of health-  several nodes. 36,40  The fact that they hinder medical data
            care blockchain applications are all improved by these   from being disclosed or accessed by attackers significantly
            contributions taken together.                      enhances the trustworthiness of PBFT.
              Moreover, using  the  POS  consensus mechanism in   4.5. RAFT
            the context of an EHR system indicates that health-care
            applications built on blockchain technology are more secure   RAFT has five server nodes with three states, namely
            and efficient in terms of making smart decisions. Real-time   leader, follower, and candidate. Modified RAFT nodes
            modifications to patient records can be made easier with   work in a category accepting the same transitions. For
            POS, which has advantages including faster transactions and   instance, if a person is selected from a category assigned
            less energy usage. In addition, the tasks of verifying patient   as a leader, he must accept clients’ requests. 37,41  The
            records are carried out by trusted health care providers who   leader must replicate the log to other servers and the
            use health care networks to ensure reliability and efficiency.    data flow from the leader to the server. The leader’s task
                                                         37
            POS is a good option for applications where timely access   is divided into three subtasks: leader election, leader
            to patient data is crucial and environmental concerns are   log replication, and safety. A new leader is elected when
            present since it combines the benefits of decentralization   the assigned leader fails to monitor the works. In log
            with a fast and streamlined consensus process, which   replication, the leader can guide and command the
            enhances the system’s overall security.            followers to execute changes made by the leader. 34,41
                                                               Finally, RAFT uses different commands for the same log
            4.3. DPOS                                          index when the server changes the state of machine for
                                                               safety concerns.  Figure  1  shows the process of cluster
            DPOS  is a  decentralized model with high efficiency  but   algorithm of RAFT.
            low consumption. There is an option to vote for creating a
            panel with restricted trusted parties known as witnesses. 33,38    By comparing these five consensus algorithms, as
            Some users act in the reputation system. It can create blocks   shown in  Figure  2, the  POW algorithm stands outs  as
            and add them to the blockchain. The DPOS census is cost-  the most efficient for the health-care sector because it
            efficient  and  time-saving.  Since  few  nodes  are  eligible   has a robust security system, which is the primary goal of
            for DPOS to be centralized, the central node can easily   initiating blockchain algorithms in health-care sectors. The
            monitor the election process. DPOS cannot maintain all   summary of compared algorithms is shown in Table 2.
            the nodes effectively, undercutting the trustworthiness in   A previous study  provides a framework for
                                                                                  29
            security. Nowadays, the health-care domain is undergoing   implementing the algorithms discussed previously, where
            advancements through the incorporation of blockchain. 34,39    a number of computers with the same specifications were
            The implementation of the DPOS algorithm ensures the   used to act as nodes for the blockchain.  By considering
                                                                                               38
            privacy of EHRs through secure transactions. With this   the typical framework with a computers of core I7, with
            technology, the patients maintain control of their EHRs.   the specifications of 16 GB memory size, and Window 10
            The patients may share their medical records with different   operating system, the experimented POW, POS, DPOS, and
            institutions.                                      PBFT algorithms with data size of 100 M/times can deliver
              Blockchain technology can ensure the privacy and   performance depicted in Figure 3. An extended period of
            security of shared data. Once a doctor updates the EHR, it   time is required to implement the proposed model in the
            is encrypted by the SHA256 hashing algorithm, and then,   system, as per empirical experiences, to compensate for the
            it is stored in a different block. 35,40  The doctor receives a   random delay between nodes.
            unique key from the patients through mail for accessing the   The  analysis  also  showed  that  the  POW  algorithm
            medical data. The DPOS algorithm secures the patient data   takes longer time compared to DPOS and POS algorithms.
            with a trustworthy guarantee and lowers the computational   Furthermore, the PBFT consensus algorithm requires
            time and minimizes the entire cost of processing EHRs.  shorter time compared to other algorithms. The performance


            Volume 1 Issue 2 (2024)                         33                               doi: 10.36922/aih.2580
   34   35   36   37   38   39   40   41   42   43   44