End-to-end delay guaranteed Service Function Chain deployment: A multi-level mapping approach

Network Function Virtualization (NFV) enables service providers to maximize the business profit via resource -efficient QoS provisioning for customer requested Service Function Chains (SFCs). In recent applications, end-to-end delay is one of the crucial QoS requirements that need to be guaranteed in SFC deployment. Whereas it has been considered in the literature, accurate and comprehensive modeling of the delay in the problem of maximizing the service provider's profit has not yet been addressed. In this paper, at first, the problem is formulated as a mixed-integer convex programming model. Then, by decomposing the model, a two-level mapping algorithm is developed, that at the first level, maps the functions of the SFCs to virtual network function instances; and in the second level, deploys the instances in the physical network. Simulation results show that the proposed approach achieves a near-optimal solution in comparison to the performance bound obtained by the optimization model, and also superiors the existing solutions.