Cost-Aware and Delay-Constrained Service Function Orchestration in Multi-Data-Center Networks
Xiang Wang, Shunliang Zhang, Yongming Wang · 2019
A virtualized network service is generally implemented via a service function chain(SFC) composed of a set of VNFs in an ordered sequence. The SFC orchestration aims to deploy SFCs on limited and distributed cloud infrastructures with various optimization targets while guaranteeing QoS requirement of the network service. In this paper, we address the problem of SFC orchestration in the multiple data centers aiming at minimizing deploying cost with delay constraint. Especially, we take into account the impact of VNFs on the link cost and multiple ingresses/egresses of SFCs. We formulate the problem as a Mixed Integer Linear Programming (MILP) model and propose a heuristic algorithm called Cost-Aware and Delay-Constrained SFC Orchestration (CADCSO) to the problem. Extensive simulation results show that CADCSO can achieve near-optimal results with much less time in small-scale network environments. Compared with the existing solution CASO, CADCSO can reduce the average cost by at least 30% and increase the acceptance ratio by around 23% in large-scale network environments. Furthermore, CADSCO outperforms CASO significantly in the case of multiple ingresses/egresses.