The wireless base station determines whether or not each wireless terminal station accessing to the wireless base station is authenticated for the access to the LAN. Thereafter, the wireless base station stores the result of the determination to the packet distributing table. When the wireless base station receives a packet from any wireless terminal station, the wireless base station determines whether or not the wireless terminal station transmitted the packet is authenticated. If the wireless terminal station is authenticated, the packet is transmitted to the LAN. On the other hand, if the wireless terminal station is not authenticated, the packet is transmitted to the server or the gateway.