19. The apparatus of claim 18 , wherein the device monitoring unit receives changed home electronic device state information from the home electronic devices connected to the home network and updates a device state library which stores the state information of home electronic devices connected to the home network based on the received home electronic device state information.
18. The apparatus of claim 13 , further comprising: a device monitoring unit which monitors states of home electronic devices which change according to control of the home electronic devices connected to the home network.