The present invention is intended to quickly download contents while preventing unauthorized contents usage. PD authentication program authenticates telephone-integrated terminal device. Server authentication program authenticate key server. Server LCM controls the reception of a request for data for identifying key server and a key from telephone-integrated terminal device. On the basis of the data for identifying key server, server LCM sends a request for the key to key server and receives the requested key from key server. Key distribution program sends the key to telephone-integrated terminal device.