Abstract
This paper describes the development of a medical information exchange system based on PKI. Using the developed secure relay system, medical institutions can transmit and receive encrypted medical information with secure MIME format, and only destination institution can decrypt the target information. This encrypted message exchanging is based on a developed public key directory service of medical institutions. In addition, we developed a function of storing medical information for emergency medical care on the system. For both exchanging and storing medical information, operations must be performed in the patient's agreement, so we also developed a status monitoring and controlling capability by patients of their own medical information on the system. The developed public key directory service is necessary for wide-area PKI based applications among medical institutions.
