To enable a user to obtain server access permission without receiving any work load.
A client 2 is provided with a reader 25 which reads the storing contents of a storing medium 4 and an access permission requesting means 26 which is connected to a server 1 by using a server address read by means of the reader 25 and requests access permission to the server 1 by transmitting the identification information of the medium 4 read by the reader 25 and the server 1 is provided with a storing means 16 which stores the identification information of the storing medium 4 to which server access is to be permitted and an access authentication control means 17 which compares the identification information of the storing medium 4 sent from the client 2 side with the identification information stored in the storing means 16 and gives the authentication of server access permission/nonpermission to the client 2 in accordance with the compared results.