COMMUNICATION SYSTEM FOR PROTECTED INFORMATION

摘要

PROBLEM TO BE SOLVED: To protect private information communicated through the Internet, etc. SOLUTION: In this communication system including a server and a client performing information exchange through a communication line, the server and client are made to have common operation history information. The operation history information is changed every time some operation is performed between the server and the client. The opposite communication parties are confirmed between the server and the client by such 'operation history information changed in every operation'.