Research On Pre-Configured Cycle Protections In Automatic Switched Optical Networks

With the rapid development of high-speed network and the requirement of service dynamics, the network survivability and protection efficiency have gained more and more attentions in recent years.The preconfigured cycle (p-cycle) can improve the network performance due to their ability to provide mesh-like efficiency and ring-like speed, which can provide much more flexibility for survivability of optical network. At the same time, the Automatic Switched Optical Networks (ASON) is regarded as the primary candidate for the controlling techniques of next generation optical networks.The survivability is always an attainable issue in ASON as it is more important for the guarantee of network operator and can provide fast restorability. With the support of Hi-Tech Research and Development Program and National Natural Science Foundation of China, the author takes wide and deep investigations on the p-cycle protection technology and takes simulations and theoretical research on the key techniques for p-cycle.The main contribution and innovation of this dissertation are described as follows:1.The theory of p-cycle model and configuration is presented under different network scenario for application as different scenarios always require different criterions.New criterions algorithms are presented for several p-cycle applications under different kinds of faults.2. A p-cycle protection model is presented under the platform of OPNET modeler, and it has been successfully added to the ASON Simulator tools.Several studies such as the asymmetric network applications, multiple failure model,dynamic traffic computation, and distributed protocol for p-cycle deployment are extended to support the analysis of the proposed approach. 3.Optimized solution of the p-cycle configuration under asymmetric network has been proposed based on the knowledge of the working capacity on each link of both directions.The mathematics model is studied to reinforce the theory studies of configuration under asymmetric network, and a practical heuristical algorithm is proposed for p-cycle configuration.4.Different approaches for candidate p-cycle election are proposed for different failure types,i.e.,single-span failure,hybrid failure.Also a two-hop tranversing method is proposed to solve the efficiency problem of the node-encircling p-cycle.The concept of the adjacent supplement cycle, chord supplement cycle and interconnected cycle are given for future researches.5.Automatic configuration and reconfiguration protocol for p-cycle application in ASON network is studied based on the previous research DCPC.The distributed flooding operation is utilized to help p-cycle configuration, and also the overhead reduction approach is studied.Besides, centric configuration and distributed configurations are compared the p-cycle configurations.To verify the performance, the results are presented in ASON Simulator.