A firewall control device controls a plurality of firewall devices provided between a core network and a plurality of sub-networks respectively, the firewall control device is configured to receive, from the plurality of firewall devices, data amount information indicating an amount of the data discarded in the plurality of firewall devices respectively and node information indicating a transmission source node of the discarded data, identify, based on the data amount information and the node information, a data flow including the discarded data which is transmitted from an information processing device indicated by the node information and of which total amount of the discarded data exceeds a threshold value, and set, in a first firewall device which is included in the plurality of firewall devices and which is coupled to the information processing device, a first discarding flow entry defining discarding of data of the identified data flow.