Blockchain Based Secret-Data Sharing Model for Personal Health Record System

The blockchain systems are analyzed under the context of the personal health record system (PHRs) requirements. The transparent property of blockchain may cause the privacy and confidentiality concerns for PHRs. The append-only storage of blockchain can be a barrier for implementing the revocability of consent in PHRs. Moreover, the health care data can be very large exceeding the practical storage capabilities of the current blockchain usages. The most important issues of blockchain include the limited storage, privacy, consent revocation, performance, energy consumption and scalability. A blockchain based secret-data sharing model is proposed by using a proxy re-encryption technique to support the PHRs in this work. Some potential attacks which can attempt on the proposed model and how the model can handle such attempts is also discussed.