On Provisioning Slices and Overbooking Resources in Service Tailored Networks of the Future

Abstract

There is a trade-off in network slicing between the twin goals of providing tailored performance and increasing resource utilisation through increased opportunities for sharing. To balance this trade-off, we propose a system consisting of assured resources, which are available if needed over the lifetime of a slice, and auxiliary resources, which are offered on a probabilistic basis in the short-term based on forecasted resource demand. We employ the practice of overbooking, which is widely used in many industries such as airlines and hotels, to increase resource utilisation when offering auxiliary resources. After deriving probabilistic results relating to the availability of auxiliary resources, we then design an algorithm to determine how much to overbook by. We also propose several ways of distributing auxiliary resource offers among slices, as well as providing an approach for dealing with overbookings. Finally, we highlight the conditions that are conducive to effective overbooking by examining the effects of varying several key system parameters, providing both analytical and numerical results.