Recently, the Japanese government has decided to introduce an electronic medical record system in hospitals and medical establishments throughout Japan. However, these will not be stand-alone systems alone, since one of the main purposes behind the government?s decision is the ability to share patient information among different medical facilities. Essentially, a medical record contains the personal data of patients. Thus, secure data transmission is required in order to share such records through the public network like the Internet. In our previous work, we defined a three layered medical information network model and a medical security gateway (MSG) which connects several hospitals by using some security enhancement technologies for public networks. Moreover, the medical open policy service (M-OPS) is considered as a security policy delivery system to MSG. In this paper, we shall describe an experimental network for realizing secure communication and an implementation of MSG and M-OPS. Unfortunately, only Secure Socket Layer technology is treated as an example of possible security enhancement technologies. However, we are convinced that the same method may be used for other security technologies.