Optical signals are transmitted in wavelengths or channels from the headend to the home, business, MDU (multi-dwelling unit) or RF tap.
These wavelengths need to be combined from transceivers, called multiplexers (muxes), onto one fiber to travel the distance. These wavelengths are then separated in a demultiplexer (demux) near the destination. The types of muxes are WDM, CWDM, DWDM, BWDM and OADM and are used for different purposes along the optical transmission.
Optical splitters are necessary in the transition of optical signals to more subscribers. The most common types of splitters are PLC (splits that are etched on a wafer) and fused (spliced fibers). Optical splitters divide a signal symmetrically and is often used in FTTx and PON networks.