Fast Resource Allocation for Virtual Network Functions Chain Placement

Network slicing enables the creation and management of a network that meets and surpasses the evolving requirements of a diverse set of new services. Within 5G network slicing, we can describe a network service as a Service Function Chain (SFC), i.e., a graph of interconnected Virtual Network Functions (VNFs) residing in a particular network slice. Thus, the optimal resource allocation for these SFCs is critical for the network operator. Nevertheless, this problem stays partially unresolved because it needs managing resources spread across various Edge and Cloud sites in distinct geographical areas. Moreover, the complexity of the problem dramatically grows when considering practical constraints like end-to-end delay, VNF affinity, processing delay, and traffic requirements between VNFs. This paper addresses this problem and proposes practical solutions for the Virtual Network Functions Chain Placement Problem (VNF-CPP) established on Integer Linear Programming (ILP) and heuristic algorithms. Furthermore, we provide theoretical analysis and experiments to demonstrate the efficiency of the proposed placement algorithms.