In a data delivery system utilizing a network 400, a data delivery server
100 receives a recording medium specifying information stored in a
recording medium 300 from a video game device 200, generates and
administers an authentication information and a password used to permit
the delivery of an event information to the video game device 200 while
relating them to the video game device 200, transmits the generated
authentication information and password to the video game device 200, and
delivers the event information to the video game device 200 upon
receiving the password as a response from the video game device 200. The
video game device 200 includes a password storage means for receiving the
authentication information and the password from the data delivery server
100 and saving the password.