Virtual Network Function Placement in Cloud Computing Environments

Abstract

Network Function Virtualization (NFV) stands out quickly as a promising innovation in telecommunication networks. It leverages the concept of cloud technology and virtualization techniques. The widespread adoption of NFV leads to providing network services through a chain of Virtual Network Functions (VNFs). This architecture is called Service Function Chain (SFC) or Virtual Network Function Forwarding Graph (VNF-FG), which can be hosted on top of commodity servers and switches located at the cloud. Meanwhile, Software-Defined Networking (SDN) can be utilized to manage VNFs to handle traffic flows through SFC/VNF-FG. One of the most critical issues that needs to be addressed in NFV is VNF placement that optimizes physical link bandwidth consumption. VNF chaining and placement can be considered as the VNF-FG mapped to a cloud provider infrastructure also called NFV Infrastructure (NFVI). Moreover, deploying SFCs enables service providers to consider different goals such as minimizing overall cost, energy consumption, and service response time. Furthermore, the continuity of cloud network services has become an essential availability requirement for NFV. Failure of VNFs may cause critical quality assurance problems for such network services. However, this mapping is addressed while neglecting the massive link utilization and bandwidth consumption that can be encountered during VNF recovery phase.