This is because SFP+ ports are backward compatible with SFP modules, but not the other way around. It's advisable to consult your vendor for precise information. An optical transceiver module is a small, hot-pluggable device used in high-speed data communication to convert electrical signals to optical signals between devices like network switches and routers. QSFP+ and QSFP28 have identical form factors but operate at different lane speeds. • Use. The question we answer below is simple: “Which of these can I mix and match without killing the link? What “compatibility” really means? All reputable transceivers follow the Multi-Source Agreement (MSA).