支持网络切片和绿色通信的软件定义虚拟化接入网

接入网络中存在大量不同的接入技术和海量的接入设备，导致运营复杂度和成本急剧增加，这迫使运营商亟待寻找一种有效的解决方案来提升收支比，以此实现可持续的商业模式.为了应对这些挑战，提出了一种基于软件定义网络(software defined networking, SDN)的新型接入网体系架构SDVAN，其可以提供具有高成本效益的网络管控机制，同时具备高扩展性并支持定制化.SDVAN将所有物理设备的控制平面抽象化集中化，并通过软件定义的方式实现对接入网的灵活定制.SDVAN节点的可编程性为不同的接入技术提供了弹性支持.此外，SDVAN还提供了一种高效的资源建模机制和网络抽象方法，实现了网络服务的自动化编排，并可基于信任级别来体现网络的可视性和可控性.最后，SDVAN实现了支持多租户和多版本网络设备的网络切片功能.实验结果证明了SDVAN方案在网络节能、资源利用率、成本等方面的有效性和实用性.

Software Defined Virtualized Access Network Supporting Network Slicing and Green Communication

Software defined networking (SDN) is disrupting the traditional networking industry by shifting network control from the physical network devices to the centralized software, thus facilitating scalability, flexibility and efficiency of the network. In the access networks, varied access technologies and massive number of access devices lead to dramatically increased OPEX, which forces operators to find feasible solutions to increase the revenue-expenditure ratio and achieve a sustainable business model. To deal with these challenges, this paper presents a new SDN-based architecture SDVAN for the access network, which provides cost-efficient network control and management with high scalability and customization support. The new architecture SDVAN abstracts control plane of all physical devices to one centralized controller which enables flexible customization of access network through software-defined fashion. The innovative node design implements a simple programmable node which naturally provides elastic support to various access technologies and efficiently improves the resource utilization. In order to automate orchestration of network services, resource modeling and network abstraction methodologies are introduced, which exposes different levels of visibility and controllability based on the trust level. Lastly, SDVAN well implements network slicing function supporting multi-tenancy and multi-version of network appliance. The theoretical analysis and experimental results prove the effectiveness and practicality of the proposed new architecture SDVAN.