A passive multiplexer in most networks consists of a mux and demux optical component. The mux combines, or multiplexes, wavelengths onto a fiber. The demux on the other end of the connection splits, or de-multiplexes, the connections.
In DWDM system, DWDM mux demux is two indispensable modules. Mux (Multiplexer) is a module at the transmitter end that brings several data signals together for transporting over a single fiber, while Demux (Demultiplexer) is a module at the receiver end that separates the signals that come together and passes each channel to an optical receiver.
CWDM mux demux (Coarse Wavelength Division Multiplexer/Demultiplexer) is a flexible, low-cost solution that enables the expansion of existing fiber capacity. CWDM multiplexer is for combining signals together, while demultiplexer is for splitting signals apart.
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