Median-pump wavelength assignment scheme for optical networks with parametric wavelength conversion

This paper proposes a wavelength assignment scheme for optical networks with parametric wavelength conversion to minimize the number of wavelength converters when the number of wavelengths is given. Wavelength conversion is needed to reduce the number of wavelengths required in the network, since the number of wavelengths is limited. A parametric wavelength converter (PWC) can be used to reduce the number of wavelength converters because of its multiple wavelengths conversion function. PWC uses the pump wavelength to define original and converted wavelengths. The setting of the pump wavelength affects the converted wavelengths. Thus, the number of transmission wavelengths depends on the position of the pump wavelength. The proposed scheme is a heuristic scheme that considers the position of pump wavelength. An output wavelength that sets the pump wavelength near to the middle of the transmission wavelength band is selected. The proposed scheme designs each PWC to maximize the number of wavelength conversions supported. Numerical results with our examined networks indicate up to 37% reduction in the total number of converters required, compared to a scheme that the position of pump wavelength is not considered. Moreover, the reduction is 42% reduction compared to an optical network with single channel wavelength converters.