A study about application to medical information system of electronic authentication technique and encryption technique of medical information

信息系统的使命是由独立的过程转变为通过互联网实现信息共享。然而，由于医疗信息是患者的私人信息，我们不能轻易地通过网络传输医疗信息。通过本研究，我们开发了网络系统，使医院之间利用互联网安全共享医疗信息成为可能。此外，我们检查了我们可以顺利共享医疗信息。该实验系统的特点是双工ATM交换机上的VLAN（虚拟局域网）、两级防火墙和VPN（虚拟专用网）。在ATM网络上建立了医院信息系统VLAN、远程诊断VLAN，医院信息系统VLAN与远程诊断VLAN之间通过内部防火墙连接，Internet与远程诊断VLAN之间通过外部防火墙连接。外部防火墙有一个名为“SOCKSVPN”的VPN系统。安装了E-mail服务器、信息共享服务器、RADIUS服务器、认证服务器、密钥管理服务器、VLAN远程诊断接入路由器等。该系统的评估是按照以下程序进行的。作为医疗信息测试数据，我们将患者信息和教育用的运动图像（MPEG）注册到信息共享服务器上，并在假设为医院外部的两种终端上对电子邮件、图像共享系统的文件传输、发送和接收进行了测试。其中一台终端通过INS64线连接到接入路由器，另一台终端通过VPN系统从Internet连接到防火墙。通过接入路由器的连接实验，首先输入安全ID卡显示的密码，就可以连接到接入路由器。一分钟后，安全ID卡显示的密码被更改，我们无法使用旧密码连接接入路由器。我们确定它的安全级别与物理密码相同。FTP传输性能为62±2kbps。通过SOCKSVPN的连接实验，当我们确认邮件到达时，第一次认证需要12±2s。第二次验证缓存后3±1s有效。在邮件中附加图形文件（95kb）时，传输时间为27±2s。使用FTP转发同一图像文件时的传输速率为51±4kbps。通过本文的研究，证明了该系统可以在不产生大延迟的情况下实现信息的安全共享。少

A mission of information system is turning from stand-alone process into information sharing by Internet. However, we cannot transmit medical information by network easily, because it is private information of a patient.By this study, we developed the network system to make safe sharing of medical information possible between hospitals using Internet. In addition, we inspected that we could share medical information smoothly.The special features of this experimental system are VLAN (Virtual LAN) on duplex ATM switches, two-stage firewall, and VPN (Virtual Private Network). We built VLAN for hospital information system, VLAN for distance diagnosis on the ATM network, and we connected with internal firewall between VLAN for hospital information system and VLAN for distance diagnosis, and connected between Internet and VLAN for distance diagnosis with external firewall. The external firewall has VPN system called "SOCKSVPN". We installed E-mail server, information sharing server, RADIUS a … More uthentication server, key management server, access router on VLAN for distance diagnosis.The assessment of this system went with the following procedure. As medical information testing data, we registered patient information and moving image (MPEG) for education to information sharing server, and we examined file transfer, transmit and receive of E-mail, pictorial image shared system with two kinds of terminal that we assumed to be hospital exterior. One of terminal was connected to the access router using INS64 line, and the another terminal was connected to fire wall from Internet with VPN system.With connection experiment by access router, At first we input the password that Secure ID card displayed, and we could connect to access router. After one minute passed, a password that Secure ID card displayed was changed, we could not connect to access router by using old password. We identified that it was security level the same as physical cipher. The transmission performance by FTP was 62±2kbps.With connection experiment by SOCKSVPN, when we confirmed mail arrival, we needed 12±2s in the first time authentication. It was 3±1s after the second time effective for authentication cache. When it attached graphic file (95 Kbytes) to mail, the transfer time was 27±2s. The transmission rate at having forwarded the same image file with using FTP was 51±4kbps.By this study, this system proved that safe information sharing was possible without big delay. Less