To attain switching of communication routes without cutting the dial-up connection at the user side.

The user information stored in a PPP server 3 and the dial-up information necessary for the dial-up connection to the server 3 are supplied from the server 3 to which a user terminal 1 is connected with dial-up via a public telephone network 2 to a WWW server 8 constructing an on-line shopping dealer equipment 7 via an internet 5. The server 8 transfers the received information to a dial-up server 9. The server 9 is connected with dial-up to the server 3 based on the dial-up information. The server 3 connects the terminal 1 to the server 9 to set up a dial-up access route based on the user information supplied form the server 9 in a dial-up connection mode.