Abstract: An apparatus and a method capable of efficiently and accurately constructing an access control configuration having high security are realized. Only the MAC address of a controller (client) 351 authorized by a user is authenticated and registered in a MAC address table of a device 352, and the device 352 performs MAC address filtering for permitting access by the controller 351 (client) which is authenticated and registered in the MAC address table. Furthermore, by making a registration completion notification and by performing version adjustment, a reliable access control configuration is constructed. The device authentication apparatus 350 avoids access from an unauthorized party which is not authenticated and registered, and makes the presence of a server not known to the controller which attempts to illegally perform device authentication. Therefore, access control with high security is realized.