The basic process is straightforward: turn the meter on, set it to the correct wavelength, clean your connectors, plug in, and read the display. Typically both transmitters and receivers have receptacles for fiber optic connectors, so measuring the. To test transmitted power in sfp optical modules, you use an optical power meter to get exact results. Many sfp modules also have DOM/DDM, which lets you see digital diagnostic monitoring data on network equipment. An optical power meter measures the strength of light traveling through a fiber optic cable, giving you a reading in dBm (decibels relative to one milliwatt). Consistent procedures ensure accuracy. During the measurement of power, the meter must be set to the proper. Accurately testing an optical Transceiver means proving two things: that the module is emitting the right power at the right wavelength, and that the link it's attached to delivers that signal without unexpected loss or reflections. In practice you'll use two complementary tools — an optical power.