Routing And Wavelength Assignment Algorithm In WDM Optical Networks

With the development of networking technologies and new services of Internet, there is an explosive growth trend of Internet traffic, which is promoting the construction of broadband backbone network. Wavelength Division Multiplexing (WDM) is a promising approach that can use the enormous bandwidth of the optical fiber. A single fiber can be employed for multiple data streams simultaneously. All-optical networks employing the concept of WDM are considered as the transport networks for the future.A key issue in networks design is to optimize Routing and Wavelength Assignment (RWA) for lightpaths. RWA solves how to find out an appropriate lightpath and assign a wavelength reasonably in order to make full use of the limited resource and provide communication capability as large as possible. In this thesis, firstly, the basic conceptions and existing algorithms for RWA problem are introduced; Secondly, a research is made on a dynamic routing and wavelength assignment algorithm in WRON considering wavelength relation in order to reduce the resources in networks, the blocking probability and the cost of wavelength assignment. Last we propose a dynamic routing and wavelength assignment algorithm utilizing the model of free wavelength based wavelength conversion degree. We adopt K shortest paths into routing and choose the best route in them considering link costs, links hops and the number of no-utilized wavelength in a link.