The Bandwidth Scheduling Technology Research Of The Optical Network Virtualization

With the rapid development of Internet technology, as well as the number of the emerging network applications grows unceasingly, the current network architecture can’t meet the rapid expansion of network size, network fossilization has become increasingly prominent. In addition, with the end users’ demand for high-capacity bandwidth keeps the continuous growth, the Internet is facing unprecedented challenges now. In order to solve the current network fossilization and high-capacity bandwidth requirements, optical network virtualization method is proposed and effectively alleviates the fossilization and bandwidth problem. On the basis of optical network virtualization technology, the concept of "IaaS" is put forward, the limited physical resource of optical network will be virtualized to a virtualization resource pool, through the resources’ s paid leasing, and release in time, which can provide the resources for more upper application services.In this paper, the key problem of optical network virtualization is resource allocation problem, especially the link bandwidth resource allocation, we have finished these research, on the basis of the analysis of existing research results, the below two kinds of virtual network link resource allocation problem are studied.First, the static virtual network mapping problem is studied, an improved two-stage joint optimization algorithm based on “the minimum hop” principle is put forward. In this algorithm, “the minimum hop” principle has been taken into consideration in the stage of link mapping, which greatly improves the physical link bandwidth utilization. In the node mapping stage, combined with the repeated use of node algorithm, while in the link map phase combined with the link segmentation technology, which makes the virtual network mapping rate increase, the physical resource utilization also improves a lot.Then the dynamic virtual network mapping problem is studied. How to allocate link bandwidth resources for the dynamic arrival virtual network request reasonably and efficiently is studied. On the basis of classic link bandwidth allocation algorithms, a dynamic link bandwidth allocation algorithm based on topology segmentation’s optimization is proposed. In this algorithm, in order to meet the demand of real-time virtual network link bandwidth resources, how to realize dynamic link bandwidth resource’s migration at minimum cost is studied. This paper described this problem as the ILP problem, and the network benefits was evaluated before and after re-mapping, according to the evaluation results, then we will decide whether to do the link dynamic migration, as well as the size of the migration.Paper uses simulation tools to do a large number of experiments and simulation of the improved algorithms, from the results of simulation, we can see that the improved algorithms make the requests of the virtual network acceptance rate, the benefits of the physical network and link bandwidth utilization ratio have a certain optimization.