Routing And Wavelength Assignment Algorithms 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 service priorities and a priority-based wavelength assignment algorithm is proposed, then by further mending the algorithm, the network integrated performance is improved; At last, the Quality of Service (QoS) problem in WDM networks is studied, and based on different service models, a QoS routing and wavelength assignment algorithm and a proportional QoS wavelength assignment algorithm are presented respectively.