ASON Network Application And Simulation Of KSP Routing Algorithm

Wavelength division multiplexing (WDM) technology is a technology that plays an important role in communication network. A single fiber can be employed for multiple data streams simultaneously. As WDM optical network exist various constraints, such as cross-blocking questions, wavelength continuity constraints and wavelength conversion, RWA issue has become the most basic and most important research topics in WDM optical network. With enduing traditional optical transport network with unprecedented flexibility and expansibility, ASON (Automatically Switched Optical Network) represented the future direction of next generation optical networks. The introduction of ASON improves flexibility of RWA scheduling in WDM optical network, and brings even greater challenge to RWA issue.As the RWA problem is very complex, RWA problem is always divided into routing sub-problem and wavelength assignment sub-problem to solve. This thesis mainly considers the routing sub-problem's impact on WDM-based ASON networks, and then proposes a K Shortest Path (KSP) algorithm as a routing sub-problem of RWA algorithm to solve RWA issue in WSON network. KSP algorithm can calculate K shortest paths for RWA to choose according network constraints. RWA algorithm can choose the most suitable route for traffic by letting KSP algorithm be the route algorithm of ASON network, and thus the assignment of network resources more rational so as to reduce the route computing time and reduce the rate of network traffic congestion. The thesis focuses on the design, implementation and improvement of the KSP routing algorithm. The main achievements are as follows:1) A KSP algorithm is proposed to be the routing sub-algorithm of RWA algorithm by analyzing RWA algorithm and various constraints of WDM-based ASON network. The KSP algorithm can calculate K shortest path for RWA to choose. Compared with traditional dynamic RWA strategy based on Dijkstra algorithm, the algorithm can reduce the route computing time and reduce the rate of network traffic congestion.2) An algorithm simulation platform is developed to verify the performance of the KSP algorithm. The simulation platform can create and modify the network topology, and view the results of Dijkstra algorithm and KSP algorithm more easily, and modify algorithm parameters whenever necessary in this platform. With comparing of these two algorithms'performance in the simulation platform, this thesis summarizes the advantage of choosing KSP algorithm as the routing algorithm in ASON network.3) In the more complex ASON networks, if the KSP algorithm is based on the minimum-hop routing strategy, the routes that calculated by the KSP algorithm would appear to be duplication and missing. In this thesis, the KSP algorithm is improved for this reason. The efficiency of the improved algorithm are increased in complex ASON network and different routing strategy.