运营商网络中面向资源碎片优化的网络服务链构建策略

网络功能虚拟化(NFV)的引入使得运营商网络的网络功能不再依赖于专用硬件设备且服务能力更具弹性。为更有效地使用基于NFV的运营商网络中的资源，该文提出一种网络服务链(NSC)的优化构建策略。和已有研究工作不同，该文从减少因计算资源和网络资源这两类资源的不合理使用产生的资源碎片角度出发，以最大化运营商网络能容纳的业务流数量为目标，建立NSC构建的数学模型，且提出一种新的贪心NSC构建策略，该策略融合了路径选择和NSC的多个VNF部署。数值仿真实验表明，在相同资源总量的情况下与典型策略相比，所提策略能够容纳更多的业务流，实现更低的端到端的数据延迟，有效提高了运营商网络中通用服务器和交换机的资源利用率。

Construction Policy of Network Service Chain Oriented to Resource Fragmentation Optimization in Operator Network

With the introduction of Network Function Virtualization (NFV), the network functions of operator networks are no longer dependent on dedicated hardware devices, and service capabilities of carrier network are more resilient than ever. For more efficient use of resources in NFV-based operator networks, this paper proposes a construction policy of Network Service Chain (NSC). This paper aims to maximize the number of flows that the carrier network can accommodate, a mathematical model is established for NSC construction from the point of view of reducing resource fragmentation due to the unreasonable use of computing resources and network resources. A new greedy NSC construction strategy is designed, which combines the path selection and multiple VNFs deployment of NSC. Numerical simulation result shows that the proposed policy can accommodate more flows and achieve lower end-to-end data latency than the typical policies in the case of the same amount of resources, which improves effectively resource utilization of the general server and switch in operator network.