Abstract: The present invention allows assuring security of processing by the application itself without depending on the operating system. When a plurality of clients perform joint operation via a common server, the processing permitted for each server to perform to the server is predetermined, and when a user requests a processing which is not permitted, the client rejects this request. By this, the security among a plurality of clients can be assured without depending on the server.
Abstract: The present invention provides a client server system whereby a message exchange can be easily executed between a client, such as a personal computer, and an Internet portable telephone. The client server system comprises a server, a plurality of clients connected to the server via communication lines, and a gateway which converts the information of the server to an interface suitable for an Internet portable telephone.