As shown in the figure, the conversion table holds in a correlated manner the area ID which is used as location information in the cellulartelephone network 22 and information such as latitude and longitude (X, Y) or administrative district (1-1-1, Toranomon, Minato-ku) and the like, which can be handled as location information by computers such as the IP servers 80A and 80B and the like.FIG. 6 is