WDM optical switching networks using sparse crossbars

We consider cost-effective designs of wavelength division multiplexing (WDM) optical switching networks for current and future generation communication systems. Based on different target applications: we categorize WDM optical switching networks into two connection models: the wavelength-based model and the fiber-link-based model. Most of existing WDM optical switching networks belong to the first category. We present new designs for WDM optical switching networks under both models by using sparse crossbar switches instead of full crossbar switches in combination with wavelength converters. The newly designed sparse WDM optical switching networks have minimum hardware cost in terms of both the number of crosspoints and the number of wavelength converters. The single stage and multistage implementations of the sparse WDM optical switching networks are considered. An optimal routing algorithm for the proposed sparse WDM optical switching networks is also presented.