A communication apparatus includes a physical layer to perform signal transmission/reception with another communication end, and a protocol conversion section (PCL) to connect an upper level user application and the physical layer. The protocol conversion section includes a parameter extraction section to extract a prescribed parameter from communication start request data (CBW) transmitted from the user application, and a header addition section to add a header containing the extracted parameter to transmission data transmitted from the user application, and the physical layer transmits the transmission data with the header.