Research Of Key Technologies In Multi-Layer And Multi-Region Intelligent Optical Networks

With the rapid development of Internet and Internet of things, the scale of optical transport networks is getting larger and larger, and the service types are also getting more and more.Large scale and dynamic are the requirement of future optical networks, and multi-layer and multi-region are the inevitable evolution trends. Although the scalability and flexibility of optical transport networks can be solved by multi-layer and multi-region, there is still quality requirement. Under the driven of large scale, dynamic and quality requirement, there are still a series of problems in multi-layer and multi-region optical networks, such as architecture scalability, service complexity, routing cooperation and network efficiency. To solve these problems, this paper mainly researches on the key technologies in multi-layer and multi-region intelligent optical networks, especially the problem of routing and resource optimization, with the support of the object-oriented project of the national high-tech research and development program "Key technologies and experiment system in large scalable multi-layer and multi-region intelligent optical networks".A number of innovative research achievements have been gained.The main work and innovative contributions of this paper can be summarized as:a novel routing engine architecture of multi-layer and multi-region is proposed. Based on this architecture, mathematical models optimized routing algorithms and resource utilization strategies are studied and simulated on the simulation platform of multi-layer and multi-region optical networks.The details are listed as follows. Firstly, to resolve the problems of architecture scalability, service complexity, routing cooperation and network efficiency in multi-layer and multi-region optical networks, a novel routing engine architecture of multi-layer and multi-region multi-constraints optical networks (DREAMSCAPE) is proposed, which includes group engine and unit engine, and the protocols and mechanisms of DREAMSCAPE are designed. The performance of dual routing schemes based on DREAMSCAPE has been simulated and compared with hierarchical routing and backward recursive PCE-based computation.Numeric results show that DRE can reduce average time of path computation and setup without increasing blocking probability compared with BRPC.Secondly, in the respect of mathematical model, the switching architecture in the local node and the complexity of the entire network are studied.The blocking probability analytical models for MG-OXC based optical networks are built and both scenarios without and with sparse wavelength conversion capabilities are considered for the first time. Some complexity laws in optical networks are discovered and summarized, based on which, a novel traffic model for optical networks considering the time-space complexity is designed which satisfactorily solves the problems that when to create connections and whom to be connected.Thirdly, in the respect of optimized routing algorithms, a dual-end recursive PCE-based computation (DRPC) procedure is proposed to compute shortest constrained inter-domain traffic engineering label switched paths which can reduce the connection establishing time and improve the network reliability. For the complexity requirement of routing and wavelength assignment algorithms in WSON, a PCE-based solution is proposed, which consists of three sub problems which are routing, resource reservation, and wavelength assignment. The solution includes a PCE-based routing framework, two PCE-based routing models, two PCE-based resource reservation schemes, and eight PCE-based wavelength assignment schemes, the performances of which have been validated using discrete event simulation tool OMNeT++.Fourthly, in the respect of resource utilization strategies, the concept of resource pre-configuration is proposed for the first time.A planning scheme of resource pre-configuration that forms a pre-configured topology different from physical topology and virtual topology has been introduced for dynamic optical networks. Simulation results show the connection establishing time could be significantly reduced.In addition, for the energy-orient problems in multi-layer optical networks, a power consumption model is built based on different service LSPs. Several PCE-based and survivable traffic grooming algorithms are designed based on the model,then simulated and analyzed using discrete event simulation tool OMNeT++.