Uncertainty-Aware Resource Provisioning for Network Slicing

Network slicing allows Mobile Network Operators to split the physical infrastructure into isolated virtual networks (slices), managed by Service Providers to accommodate customized services. The Service Function Chains (SFCs) belonging to a slice are usually deployed on a best-effort premise: nothing guarantees that network infrastructure resources will be sufficient to support a varying number of users, each with uncertain requirements. Taking the perspective of a network Infrastructure Provider (InP), this article proposes a resource provisioning approach for slices, robust to a partly unknown number of users with random usage of the slice resources. The provisioning scheme aims to maximize the total earnings of the InP, while providing a probabilistic guarantee that the amount of provisioned network resources will meet the slice requirements. Moreover, the proposed provisioning approach is performed so as to limit its impact on low-priority background services, which may co-exist with slices in the infrastructure network. Taking all these constraints into account leads to an integer programming problem with many nonlinear constraints. These constraints are first relaxed to get an integer linear programming formulation of the slice resource provisioning problem. This problem is then solved considering the slice resource provisioning demands jointly. A suboptimal approach is finally proposed where slice resource provisioning demands are considered sequentially. Both solutions are compared to provisioning schemes that do not account for best-effort services sharing the common infrastructure network, as well as uncertainties in the slice resource demands.

I. Introduction

Network slicing will play an essential role in 5G communication systems [1]–[3]. Leveraging network function virtualization, network slicing reduces overall equipment and management costs [4] by increasing flexibility in the way the network is operated [5]. Multiple dedicated end-to-end virtual networks or slices can be managed in parallel over a given infrastructure network owned by one or several Infrastructure Providers (InPs). With network slicing, vertical markets can be addressed: Customers can manage their own applications by exploiting built-in network slices tailored to their needs [6].