WDM is the common abbreviation for Wavelength division multiplexing. WDM uses multiple lasers and transmits multiple wavelengths of Light over a single optical fiber.

WDM has increased the carrying capacity of fiber optic Cables and also made it possible for Data to flow both ways in a single strand of fiber. By adjusting the data streams into a different part of the light Spectrum several types of data are able to travel on its own unique color band.

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