Study Of Routing And Wavelength Assignment Problem In WDM All Optical Networks

How to assign fiber and wavelength efficiently is not only important but also difficult in WDM networks. This thesis proposes a RWA model that aims at game theory after we have a comprehensive acquaintance about past RWA algorithm. In this RWA model, each connection request is assigned a value, which denotes the price the user of this request will pay to WDM network when it is successfully responded. It is a gaming process for responding connection requests. The goal of this thesis is to maximize the summation value of all of the successfully responded connections after all of the connection requests have given their value.This thesis proposes a RWA algorithm for the proposed model called LPC-RVL algprithm. LPC-RVL algorithm divides RWA problem into routing subproblem and wavelength assignment subproblem. Conception of link cost is introduced to routing algorithm. The cost of a link is the reciprocal of the number of available wavelengths on the link. Dijkstra algorithm is used to find a shortest path for all of the requests. Conceptions of related connection requests and value loss are introduced to wavelength assignment algorithm. According to a computational method, the wavelength that has minimal summation of value loss for all of the connection requests in set of related connection requests will be chosed.In order to estimate to performance of LPC-RVL algorithm proposed in this thesis, a common RWA algorithm is realized called LHC-FF algorithm. LHC-FF algorithm also uses Dijkstra algorithm to find a route. However, the cost of each link doesn't change with the number of available wavelengths on this link. The cost keeps one until the number of available wavelengths becomes to zero when the cost of this link becomes infinite. Wavelength assignment algorithm uses classical First-Fit algorithm. According to experiment data, it can be seen that LPC-RVL algorithm has better performance for the RWA problem model proposed in this thesis.