基于SDN特征的虚拟网络映射问题研究

Network virtualization is one of the key research directions of future network field. The concept of software-defined networking (SDN) brings new energy for network virtualization. This study will focus on the SDN-character-based virtual network embedding technology. Firstly this study will build a new system model for virtual network embedding problem based on the new characters of SDN, which are bandwidth, storage, and computing. The new model will become the base of the following studies. Secondly, the tracking problem of varieties dynamic virtual requests will be addressed by building a standard processing framework. Thirdly, a one-step virtual network embedding algorithm will be proposed based on model coupling for better performance to enhance performance. Fourthly, a multi-steps virtual network embedding algorithm will be proposed based on objective coupling for better balance of complexity and performance. Fifthly, a distributed virtual network embedding algorithm will be proposed based on synchronization protocol in order to deal with the scalable problem for the embedding problem. Last but not the least, the software/hardware simulation platforms based on the C programming language and OpenFlow technology are developed to evaluate the model and algorithms proposed in this study. And the simulation results will be referenced in the designing. The study may contribute in the solution system of SDN-based virtual network embedding problem.

网络虚拟化技术是未来网络领域的重要研究方向之一，软件定义网络（SDN）思想的提出则为该方向带来了新的活力。本课题将研究基于SDN特征的虚拟网络映射问题。首先,本课题将围绕带宽、存储、计算三个SDN的新特征，为虚网映射问题重新建模，作为后续研究的基础；其次，通过设计统一的处理框架，规范解决虚网请求的各种动态性跟踪问题；接下来，为了提升虚网映射性能,设计基于模型耦合的一步式虚网映射算法；为了实现算法复杂度与性能的有效权衡，设计基于优化目标直接耦合的分步式虚网映射算法；为了解决可扩展性问题，设计基于同步协议的分布式并行映射算法；最后，建立基于C语言的软件仿真平台和基于OpenFlow的硬件仿真平台，分别对本课题提出的模型和映射算法进行仿真与验证，并反馈指导模型和算法的设计。研究结果有望形成适用于SDN的虚网映射体技术整体解决方案。

未来网络领域中，网络虚拟化技术是重要的研究方向，软件定义网络（SDN）思想的提出更是为该方向带来了新的发展机会。本项目主要研究网络虚拟化中的虚拟网络映射问题和SDN控制平面优化技术，同时构建原型系统。首先,本课题为虚网映射问题进行了重新建模，将之主要分为了基于节点连接关系和基于实时拓扑信息的虚拟网络映射问题；这一模型为之后的研究打下了基础。其次，之后，为了提升虚网映射性能, 设计出基于模型耦合的一步式虚网映射算法；为了实现算法复杂度与性能的有效权衡，设计出基于优化目标直接耦合的分步式虚网映射算法；最后，建立了基于C 语言的软件仿真平台CNVP和基于OpenFlow 的硬件仿真平台，分别对本课题提出的模型和映射算法进行仿真与验证，并反馈指导模型和算法的设计。研究结果形成了从理论到实践上均适用于SDN 的虚网映射体技术整体技术方案。