Patent ID: 7440444

Claim:
An IP telephone system comprising: an IP (Internet Protocol) telephone apparatus that is connected to an IP network; a Web server that stores ring tone information corresponding to a telephone number assigned to said IP telephone apparatus, and transmits, to said IP telephone_apparatus, the ring tone information in response to a request from said IP telephone apparatus; and an ENUM (Telephone Number Mapping) server that stores a NAPTR (Naming Authority Pointer) resource record in which a URI (Uniform Resource Identifier) specifies link data related to the ring tone information that is stored in said Web server, and transmits, to said IP telephone apparatus, the NAPTR resource record in response to a query from said IP telephone apparatus, the link data linking the NAPTR resource record stored in the ENUM server with the ring tone information stored in said Web server, wherein said IP telephone apparatus, when a call is received, transmits, to said ENUM server, a query for a NAPTR resource record associated with an intended recipient telephone number, transmits, to said Web server, a request for the ring tone information corresponding to the intended recipient telephone number, associated with the obtained NAPTR resource record, and sounds a ring tone based upon the obtained ring tone information.