CLOSED AREA GROUP COMMUNICATION SYSTEM, MANAGEMENT SERVER SYSTEM, COMMUNICATION TERMINAL AND THEIR PROGRAM STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To build up a virtual private network VPN independently of a physical condition of a network such as a terminal utilizing IP address and a work place for the user in the case of building up the virtual private network VPN on the network using the TCP/IP. SOLUTION: User Ids and passwords of all users using a network are registered by a management server 5 and an IC card 7 (A-D) is distributed to all the users. Furthermore, an authentication/encryption software and an IC card reader are provided to all terminals 1-4 on the network. The management server 5 configures a VPN in the unit of the user Ids and each user when using the network uses the IC card of the terminal and the user ID/password to receive the authentication by the management server 5. In this case, the management server 5 registers the IP address of the user terminal made to correspond to the VPN to which the user belongs so as to allow terminals used by users belonging to the same VPN to configure the VPN.