RELAY DEVICE, RELAY METHOD, AND PROTOCOL

PROBLEM TO BE SOLVED: To efficiently perform transmission of response data in relaying communication between a master device which is compliant to a first protocol and transmits a request command and a slave device which is compliant to a second protocol and transmits response data.SOLUTION: A relay device comprises: a request command conversion unit 11 for receiving a request command, converting the request command according to a second protocol, and transmitting the converted request command to a slave device 3; a header creation unit 12 for creating a header; a header/data transmission time determination unit 15 for controlling header transmission timing so that transmission of converted response data starts immediately after completion of transmitting the header; a transmission timing control unit 16 for transmitting the header to a master device 2; and a data conversion unit 13 for receiving the response data from the slave device 3 and converting the response data according to a first protocol before the converted response data is transmitted to the master device 2 by the transmission timing control unit 16.