To test transmitted power in sfp optical modules, you use an optical power meter to get exact results. The TX (transmit) and RX (receive) power levels significantly affect everything from signal strength to transmission distances and the overall optical power. In optical networking, one of the key aspects during commissioning is ensuring that the optical input power (Rx) falls within the recommended range specified by the transceiver vendor. The average transmission optical power refers to the optical power output by the light source at the. The optical module serves as a crucial component in optical fiber communication systems, operating at the physical layer, which is the lowest layer in the OSI model. Its primary function is to achieve optoelectronic conversion by converting electrical signals into optical signals and vice versa.