Research On Algorithms For Routing And Wavelength Assignment (RWA) 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.Wavelength routing optical network (WRON) is a practicable technology for next-generation high-speed backbone networks. Due to the limitation of wavelength resource, it is an important problem in WRON that how to utilize limited wavelength resources and improve the blocking probability of the networks by improving the capacity of the networks. There are two methods to solve the above problem. One is by using optimal routing and wavelength assignment (RWA), the other is by using optimal configuration of wavelength conversion. A key issue in networks design is to optimize Routing and Wavelength Assignment (RWA) for light paths. RWA solves how to find out an appropriate light path 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, a good many aspects of the WDM optical networks are introduced, such as the arisen background, the survey of research, the framework, the characteristic, and so on. Then set forth the prospect of development of the WDM technology. In addition, the basic conceptions and existing algorithms for RWA problem are presented. And the RWA problem in static and dynamic network situation of all-optical networks has been deeply studied. At last, a research is made on service priorities and a priority-based wavelength assignment algorithm is proposed, the network integrated performance is improved. The simulation results have proved the validity of this algorithm.