Division multiplexing based on separation, wavelength (WDM) is a form of technology in optical communication is several signal modulated on the carrier frequency of the optical on a fiber optical division multiplexing. This works by using different wavelengths (different colors) of laser light. this means that any signal on a wavelength (color) are placed and then all the wavelengths (colors) over a fiber, and for a time are sent. The work capacity of an optical fiber to send information a few times. Also, it is possible to send (two-sided) information from the two ends of a fiber, the NIR provides. Such a method in a telecommunication radio called re-multiplexing, based on the breakdown frequency (FDM) is known, but in optical communication, to name a WDM be known.