In wavelength routing, a fixed wavelength is used for the optical connection between two communicating optical network nodes in an optical network
. In wavelength routing, a wide variety of optical components can be used for routing. Important components for wavelength routing are wavelength division multiplexers (WDM) in their various forms such as CWDM, WWDM or DWDM, wavelength switches, wavelength converters and optical switching components such as optical add/drop multiplexers (OADM) and ROADMs
. In wavelength routing, the transmission path is defined by the optical network.
This may be an all-optical path over multiple fiber links. In such a configuration, the entire bandwidth is available to the transmission path. By using wavelength multiplexers, up to one hundred different color wavelengths can be available for transmission on one optical fiber of an optical transmission path, depending on the wavelength multiplex.