Implementation of Blockchain Technology Using Hash Method in Java for Medical Record Application Development

Health problems are not only related to the availability of medical facilities and medical personnel but also include the security of health data. In this regard, the development of blockchain technology provides a bright spot for data protection. This group’s research is intended to discuss the application of blockchain technology in the health sector, to protect patient medical record data. Therefore, in this study, an analysis of several kinds of literature has been collected to find out how the blockchain works. The analysis results found that one of the blockchain elements is the hash. The hash function takes input using a variable length and then produces a fixed-length output. Using a hash algorithm, transactions that are taken as input, are output with a fixed size. The hash function as a blockchain element is then implemented using the Java language to protect medical record data when it is stored and shared among hospitals using medical record applications.