Research On Optimization And Modeling Of Routing Planning In Transport Networks

With the explosive growth of network traffic, transport network develops rapidly as the foundation of the whole telecommunication network. The network scale and business types of transport network is increasingly expanding, more complex network model appear. These put forward higher requirements for the transport network network planning and network management, the existing routing algorithms have been difficult to meet the requirements of efficient centralized management of the future transport network.Concerning Network planning and optimization in transport network, it is necessary to consider many features about optical network, which affect route planning are transmission losses of optical signal, wavelength consistency, OEO(Optical-Electrical-Optical) resource allocation, wavelengths resource allocation and so on, while these features present a great challenge for optical network algorithms design. Under the existing network resources, how to optimize the use of network resources, not only related to more users are able to get high-quality services, but also related to the development of the network stability. Existing network optimization models pay less attention to OEO distribution, or optical signal transmission loss constraint expression is unreasonable, and the lack of research on the regeneration reservation, re-routing and other issues.In this thesis, starting from several important issues of the optical transport network, research the route planning in the transport network and create ILP(Integer Linear Programming) models for different scenarios. First, compare different network optimization modeling methods, namely Node-Link Model and Link-Path Model, to analyze the strategy of modeling methods selection under different scenarios. Then, analyze the impact of different network topologies for network transport network performance under different routing scenarios, which contain OEO distribution, OEO aside, re-routing calculation and so on. Based on the above analysis, summarize the transmission loss of the transport network, regenerative repeater placement, the number of key factors on the transport network and other resources how to affect network performance. Meanwhile, in the above scenario the impact of different algorithms strategies are compared through study the results of the optimization, such as the OEO reservation problem. Finally, with regard to the re-routing model, which is complex, propose a Lagrangian Relaxation algorithm to reduce model complexity while at the algorithmic level to solve the problem. In addition, the results of ILP models can provide a basis for algorithm verification.Through the above work, this thesis use optimization models analyze transport network to summarize the impact of network topology on transport network performance, and provide a theoretical basis for network planning. Meanwhile, this thesis can provide new ideas for algorithm designed from the perspective of network optimization.