Terminals are connected via cables in a star-shaped fashion with respect to a HUB in a LAN. Each of the cables includes therein signal lines and power feed lines. The HUB includes therein a power feed section. The power feed section and the power feed lines of each cable are connected to measure a value of current which flows in the power feed lines. If it is judged based on the measured current value that the terminal connected to the corresponding cable is a telephone terminal, the power feeding to the corresponding power feed lines is continued. On the other hand, if the terminal is judged to be a terminal other than the telephone terminal, the power feeding is stopped.