To notify various information to users using an information display phone which usually notifies information only on the caller when a call arrives.

A VoIPGW device 2 acquires various information from an information server 3 on the IP network 4 and converts the information into data for modem signals. In an arbitrary timing, the VoIPGW device 2 executes a pseudo-incoming operation by a caller information display function with respect to an information display phone 4 being used by the user, and displays the various information in a display portion of the phone. After executing the incoming operation for displaying information, if the VoIPGW device 2 continues the incoming operation, the phone itself rings, so the VoIPGW device 2 abandons the incoming operation.