在虚拟网络功能服务链(VNF-SC)中, 当用户申请服务请求, 网络运营商为请求分配频谱和互联网技术(IT)资源后, 由于业务请求、释放资源时间均不相同, 经常出现频谱资源利用率低、产生频谱碎片和阻塞后续VNF-SC请求的情况。提出了一种用于数据中心间的弹性光网络(IDC-EON)优化VNF-SC部署的联合多段路径算法, 该算法以数据中心为边界, 将每个端到端路径划分为多个路径段, 考虑频谱资源开销和利用率对每个路径段的影响, 选择目标函数值最小的端到端路径部署VNF-SC。仿真结果表明, 所提出的算法比现有算法阻塞率更低。

In the virtual network functions service chain(VNF-SC), When a user applies for a service request and the network operator allocates spectrum and Internet technology(IT) resources for the request, due to the different service requests and resource release times, the spectrum resource utilization is often low, spectrum fragments are generated, and subsequent VNF-SC requests are blocked. A joint multi segment path algorithm for optimizing VNF-SC deployment in elastic optical network (IDC EON) between data centers is proposed. The algorithm divides each end-to-end path into multiple path segments with the data center as the boundary, and considers the impact of spectrum resource overhead and utilization on each path segment, selects the end-to-end path with the smallest objective function value to deploy the VNF-SC. The simulation results show that the proposed algorithm has a lower blocking probability than existing algorithms.