A system comprising a plurality of control apparatuses, each control apparatus configured to control either a plurality of slave station apparatuses (20-1 to 20-6), a plurality of master station apparatuses (10-1 to 10-6), or a transfer apparatus (30-1 to 30-4), each of the plurality of master station apparatuses is connected to one or more slave station apparatuses(20-1 to 20-6), each of the plurality of master station apparatuses controlling the connected one or more slave station apparatuses, and the transfer apparatus (30-1 to 30-4), being a switch for transferring data transmitted and received between a master station apparatus and a slave station apparatus, each control apparatus comprising: an information acquisition unit (401b-1 to 401b-8) configured to acquire information regarding traffic of the data transmitted and received between the master station apparatus and the slave station apparatus; a switching control unit (402b-1 to 402b-8) configured to perform switching-control of an assignment relationship between the master station apparatus and the slave station apparatus and perform switching-control of a transfer path of data between the master station apparatus and the slave station apparatus, on the basis of the information regarding the traffic acquired by the information acquisition unit (401b-1 to 401b-8); wherein each control apparatus further comprises an information sharing unit (404b-1 to 404b-4) configured to transmit connection device information regarding processing resources of the master station apparatus and information of the slave station apparatus assigned to the master station device to which the control apparatus is connected to another control apparatuses and receive connection device information regarding a master station apparatus, or a slave station apparatus to which another control apparatus is connected, and the switching control unit (402b-1 to 402b-8, 404c) is configured to perform the switching-control of the assignment relationship and the switching-control of the transfer path of data only on any one apparatus of one or more master station apparatuses and one or more slave station apparatus and a transfer apparatus (30-1 to 30-4) that are connected to the control apparatus, using the connection device information received by the information sharing unit and the information regarding the traffic acquired by the information acquisition unit. an information acquisition unit (401b-1 to 401b-8) configured to acquire information regarding traffic of the data transmitted and received between the master station apparatus and the slave station apparatus; a switching control unit (402b-1 to 402b-8) configured to perform switching-control of an assignment relationship between the master station apparatus and the slave station apparatus and perform switching-control of a transfer path of data between the master station apparatus and the slave station apparatus, on the basis of the information regarding the traffic acquired by the information acquisition unit (401b-1 to 401b-8); wherein each control apparatus further comprises an information sharing unit (404b-1 to 404b-4) configured to transmit connection device information regarding processing resources of the master station apparatus and information of the slave station apparatus assigned to the master station device to which the control apparatus is connected to another control apparatuses and receive connection device information regarding a master station apparatus, or a slave station apparatus to which another control apparatus is connected, and the switching control unit (402b-1 to 402b-8, 404c) is configured to perform the switching-control of the assignment relationship and the switching-control of the transfer path of data only on any one apparatus of one or more master station apparatuses and one or more slave station apparatus and a transfer apparatus (30-1 to 30-4) that are connected to the control apparatus, using the connection device information received by the information sharing unit and the information regarding the traffic acquired by the information acquisition unit.