Energy-efficient virtual network function placement in telecom networks

Network Function Virtualization (NFV) is an emerging network architecture, which decouples the software implementation of network functions from the underlying hardware. Telecom operators widely place diverse types of Virtual Network Functions (VNFs) on specified software middlebox. Traffic needs to go through a set of ordered VNFs which forms a Service Function Chain (SFC). However, how to efficiently place VNFs at various network locations while minimizing energy consumption is still an open problem. To this end, we study joint optimization of VNF placement and traffic routing for energy efficiency in telecom networks. We first present the energy model in NFV-enabled telecom networks, and then formulate the studied problem as an Integer Linear Programming (ILP) model. Since the problem is NP-hard, we design a polynomial algorithm using the Markov approximation technique to find the near-optimal result. Extensive simulation results show that our algorithm saves up to 14.84% energy consumption in telecom networks compared with previous VNF placement algorithms.