A control device that controls a transfer device, includes a memory and a processor coupled to the memory and configured to evaluate, for each of a plurality of processing rules to be used to process a packet in the transfer device, a processing load caused upon identification of a packet matching the processing rule, based on the type of an application requirement identifying the packet to which the processing rule is applied, generate, as a table to be used by the transfer device, a rule table storing the plurality of processing rules in order from the lowest processing load to the highest processing load, and transmit, to the transfer device, a control packet to request the transfer device to set the rule table.