A transport apparatus comprising: a client signal transceiving unit which transceives a client signal; a mapping unit which maps the received client signal to a first transport frame; a transmission-side rate conversion unit which performs rate conversion on the first transport frame to generate a second transport frame; a line signal transceiving unit which converts the second transport frame obtained by the rate conversion into an optical signal, transmits the converted optical signal as a line signal, converts a received line signal into an electrical signal, and outputs an electrical line signal; a reception-side rate conversion unit which performs rate conversion on a third transport frame included in the electrical line signal to generate a fourth transport frame; and a demapping unit which extracts a client signal from the fourth transport frame and outputs the extracted client signal to the client signal transceiving unit, wherein the transport apparatus is characterized in that the client signal transceiving unit transceives the client signal with a first transfer rate, and the line signal transceiving unit transceives the line signal with a second transfer rate, the mapping unit sets the client signal received with the first transfer rate in the first transport frame that is compliant with a third transfer rate, the transport apparatus comprises a transmission-side framing processing unit which inserts a dummy signal having a deficient data amount for transfer with the third transfer rate into the first transport frame and transmits the first transport frame with the third transfer rate, the transmission-side rate conversion unit sets the client signal set in the first transport frame received from the transmission-side framing processing unit in the second transport frame that is compliant with the second transfer rate and transmits the second transport frame with the second transfer rate, the reception-side rate conversion unit sets a client signal in the third transport frame received with the second transfer rate as the electrical line signal in the fourth transport frame that is compliant with the third transfer rate, inserts a dummy signal having a deficient data amount for transfer with the third transfer rate into the fourth transport frame, and transmits the fourth transport frame with the third transfer rate, and the demapping unit extracts the client signal set in the fourth transport frame received from the reception-side rate conversion unit and transmits the extracted client signal to the client signal transceiving unit with the first transfer rate. a client signal transceiving unit which transceives a client signal; a mapping unit which maps the received client signal to a first transport frame; a transmission-side rate conversion unit which performs rate conversion on the first transport frame to generate a second transport frame; a line signal transceiving unit which converts the second transport frame obtained by the rate conversion into an optical signal, transmits the converted optical signal as a line signal, converts a received line signal into an electrical signal, and outputs an electrical line signal; a reception-side rate conversion unit which performs rate conversion on a third transport frame included in the electrical line signal to generate a fourth transport frame; and a demapping unit which extracts a client signal from the fourth transport frame and outputs the extracted client signal to the client signal transceiving unit, wherein the transport apparatus is characterized in that the client signal transceiving unit transceives the client signal with a first transfer rate, and the line signal transceiving unit transceives the line signal with a second transfer rate, the mapping unit sets the client signal received with the first transfer rate in the first transport frame that is compliant with a third transfer rate, the transport apparatus comprises a transmission-side framing processing unit which inserts a dummy signal having a deficient data amount for transfer with the third transfer rate into the first transport frame and transmits the first transport frame with the third transfer rate, the transmission-side rate conversion unit sets the client signal set in the first transport frame received from the transmission-side framing processing unit in the second transport frame that is compliant with the second transfer rate and transmits the second transport frame with the second transfer rate, the reception-side rate conversion unit sets a client signal in the third transport frame received with the second transfer rate as the electrical line signal in the fourth transport frame that is compliant with the third transfer rate, inserts a dummy signal having a deficient data amount for transfer with the third transfer rate into the fourth transport frame, and transmits the fourth transport frame with the third transfer rate, and the demapping unit extracts the client signal set in the fourth transport frame received from the reception-side rate conversion unit and transmits the extracted client signal to the client signal transceiving unit with the first transfer rate.