A communication system comprising a plurality of transceiver devices each having a transmission device that transmits unit data obtained by dividing data by a predetermined unit in order to transmit and receive the data and a reception device that receives the unit data transmitted by the transmission device, the communication system configured that: the plurality of transmission devices (110,120, 130, 140) are connected in series; and each of the transmission devices includes: a transmission device identification information storing means configured to store transmission device identification information for identifying the device itself; a unit data accepting means configured to accept the unit data from a device connected to a front stage side with respect to the device itself; a transmission device identification information generating means configured to generate transmission device identification information for identifying any one of the plurality of transmission devices (110, 120, 130, 140) from in-unit-data information included in the accepted unit data, in accordance with a predetermined generation process; a unit data transmitting means configured to, in a case that the generated transmission device identification information corresponds to the stored transmission device identification information, transmit the accepted unit data to the reception device configuring the transceiver device together with the transmission device; and a unit data sending means configured to, in a case that the generated transmission device identification information does not correspond to the stored transmission device identification information, send the accepted unit data to a transmission device connected to a back stage side with respect to the device itself. the plurality of transmission devices (110,120, 130, 140) are connected in series; and each of the transmission devices includes: a transmission device identification information storing means configured to store transmission device identification information for identifying the device itself; a unit data accepting means configured to accept the unit data from a device connected to a front stage side with respect to the device itself; a transmission device identification information generating means configured to generate transmission device identification information for identifying any one of the plurality of transmission devices (110, 120, 130, 140) from in-unit-data information included in the accepted unit data, in accordance with a predetermined generation process; a unit data transmitting means configured to, in a case that the generated transmission device identification information corresponds to the stored transmission device identification information, transmit the accepted unit data to the reception device configuring the transceiver device together with the transmission device; and a unit data sending means configured to, in a case that the generated transmission device identification information does not correspond to the stored transmission device identification information, send the accepted unit data to a transmission device connected to a back stage side with respect to the device itself. a transmission device identification information storing means configured to store transmission device identification information for identifying the device itself; a unit data accepting means configured to accept the unit data from a device connected to a front stage side with respect to the device itself; a transmission device identification information generating means configured to generate transmission device identification information for identifying any one of the plurality of transmission devices (110, 120, 130, 140) from in-unit-data information included in the accepted unit data, in accordance with a predetermined generation process; a unit data transmitting means configured to, in a case that the generated transmission device identification information corresponds to the stored transmission device identification information, transmit the accepted unit data to the reception device configuring the transceiver device together with the transmission device; and a unit data sending means configured to, in a case that the generated transmission device identification information does not correspond to the stored transmission device identification information, send the accepted unit data to a transmission device connected to a back stage side with respect to the device itself.