Virtual network embedding for power savings of servers and switches in elastic data center networks

Currently, the elastic interconnection has realized the high-rate data transmission among data centers (DCs). Thus, the elastic data center network (EDCN) emerged. In EDCNs, it is essential to achieve the virtual network (VN) embedding, which includes two main components: VM (virtual machine) mapping and VL (virtual link) mapping. In VM mapping, we allocate appropriate servers to hold VMs. While for VL mapping, an optimal substrate path is determined for each virtual lightpath. For the VN embedding in EDCNs, the power efficiency is a significant concern, and some solutions were proposed through sleeping light-duty servers. However, the increasing communication traffic between VMs leads to a serious energy dissipation problem, since it also consumes a great amount of energy on switches even utilizing the energy-efficient optical transmission technique. In this paper, considering load balancing and power-efficient VN embedding, we formulate the problem and design a novel heuristic for EDCNs, with the objective to achieve the power savings of servers and switches. In our solution, VMs are mapped into a single DC or multiple DCs with the short distance between each other, and the servers in the same cluster or adjacent clusters are preferred to hold VMs. Such that, a large amount of servers and switches will become vacant and can go into sleep mode. Simulation results demonstrate that our method performs well in terms of power savings and load balancing. Compared with benchmarks, the improvement ratio of power efficiency is 5%-13%.