Optical splitters are passive devices that split a single optical signal into multiple signals or combine multiple signals into a single one. As passive devices, they do not require an external power source to operate, relying solely on the properties of light transmission through. A splitter is not a filter like a wavelength division multiplexer (WDM). Rarely, there can be two inputs to provide potential redundancy of route. Whether in FTTH deployments, 5G fronthaul, data centers, or long-haul transmission, the use of appropriate passive.