Dynamic Wavelength Assignment in Cognitive Optical Network

This paper investigates the problem of wavelength assignment in dynamic wavelength reusable multicarrier distributed (WRMD) wavelength-divisionmultiplexing (WDM) networks. In WRMD network lightpath between source and destination edge nodes (ENs) are established by using multi-carrier light source (MCLS). An MCLS is a communication light source device that can generate multiple optical carriers at the same time with accuracy. Optical carrier regeneration reduces the number of wavelengths used for lightpath establishment, the allowable number of carrier regeneration per wavelength must be limited because the quality of the regenerated after carrier regeneration. This paper formulates the wavelength assignment problem, minimizing the number of wavelengths needed to establish all request lightpaths, as the graph coloring problem numerical results indicate that our developed algorithm performs well in our test cases. It is observed that one and two carrier regeneration per wavelengths for lightpath establishment by approximately 30% to 40% respectively, compared to that without carrier regeneration.