Reshaping the mobile core network via function decomposition and network slicing for the 5G Era

Industrial and academic focus in recent years has been shifting towards the Fifth Generation Mobile Networks (5G). In the horizon 2020, the key improvements will rely on technical breakthroughs in the radio access networks, mainly to bring increased bandwidth to the user devices. However, there is still much discussion ongoing about the evolution required in the core network to accommodate increased demands from existing services (e.g. in the number of devices) and services which are not feasible or efficiently implemented with today's architecture. Disruptive approaches can even be considered if the horizon for such changes is extended to 2025. Due to the advance of virtualization and SDN technologies, it is very promising that the current mobile core network could gain more flexibility, support multiple radio access network generations in parallel, and meanwhile enrich its ecosystem to generate new revenue opportunities. In this paper, we would like to discuss the feasibility to design a flexible and adaptive mobile core network based on functional decomposition and network slicing concepts. This paper will provide a guideline and enlighten strategic directions for future mobile core network research.