To enhance convenience of delivering via the Internet by portable terminal equipment by enhancing flexibility of selecting using conditions between the respective portable terminal equipment, and enhancing dealing capability at the equipment during emergency times.

A portable terminal system comprises a plurality of portable terminal equipment, having prescribed mutual relations and a managing center for managing communication between communication networks, including communication networks connected with the equipment and storing the mutual relations between the equipment. Thus, the system can set and change, using conditions between the equipment, based on the mutual relations.