A device, a method and a server for performing device identification of electric appliances connected to a network are provided. An information processing device, to which electric appliances are communicably connected via a network, receives a packet (a response packet and/or a passive packet) for determining a type of an electric appliance, from the electric appliances. The information processing device stores definition files defined for each electric appliance in advance, compares the received packet with the definition files for the each electric appliance, scores the packet, extracts a definition file with a high score, and determines electric appliance information of the extracted definition file as electric appliance information of the electric appliance.