A communication system includes: a plurality of nodes each of which requests a processing rule for processing a received packet; and a control apparatus that determines in response the request a processing rule corresponding to the received packet and notifies the determined processing rule to at least one of the plurality of nodes. One of the plurality of nodes forwards to the control apparatus a first packet for acquiring a destination address for a predetermined communication. The control apparatus in response to determination of the destination address determines a processing rule for processing a second packet to be transmitted to the destination address and notifies the determined processing rule to at least one of the plurality of nodes.