Resumen
In recent years, several hospitals have begun using health information systems to maintain electronic health records (EHRs) for each patient. Traditionally, when a patient visits a new hospital for the first time, the hospital?s help desk asks them to fill in relevant personal information on a piece of paper and verifies their identity on the spot. This patient will find that many of her personal electronic records are in many hospital?s health information systems that she visited in the past, and each EHR in these hospital?s information systems cannot be accessed or shared between these hospitals. This is inconvenient because this patient will again have to provide their personal information. This is time-consuming and not practical. Therefore, in this paper, we propose a practical and provable patient EHR fair exchange scheme for each patient. In this scheme, each patient can securely delegate the information system of a current hospital to a hospital certification authority (HCA) to apply migration evidence that can be used to transfer their EHR to another hospital. The delegated system can also establish a session key with other hospital systems for later data transmission, and each patient can protect their anonymity with the help of the HCA. Additionally, we also provide formal security proofs for forward secrecy and functional comparisons with other schemes.