a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths (i.e., colors) of laser light. This technique enables bidirectional communications over one strand of fiber, as well as multiplication of capacity.

Dr. David Huber and Kevin Kimberlin co-founded Ciena Corp., the venture that led to the global adoption of the high-capacity light amplification technology, based on the work of American physicist Gordon Gould. Their venture patented the dual-stage, all-optical amplifier and commercialized the first dense Wave Division Multiplexing (WDM) system, the massive capacity technology powered the internet explosion of the 1990s. 

Today WDM is the common basis of all metro, regional, national, intercontinental and transoceanic communications networks and the foundation of the internet.