A bridging apparatus includes an address-table managing unit configured to manage an address table in which devices connected to networks are registered, a presence-check-frame transmission control unit configured to transmit a presence check frame for checking whether a device is connected to a network, and a network transmission-reception control unit configured to call, upon receipt of a response request frame transmitted from a first device connected to a first network toward a second device connected to a second network, the address-table managing unit to register the first device in the address table and check whether the second device is registered in the address table, and when the second device is registered, transmit an acknowledgement to the first device and transfer the response request frame to the second network, whereas when the second device is not registered, instruct the presence-check-frame transmission control unit to transfer the response request frame to the second network.