  To accommodate various use cases with differing characteristics, the Fifth
Generation (5G) mobile communications system intends to utilize network
slicing. Network slicing enables the creation of multiple logical networks over
a shared physical network infrastructure. While the problems such as resource
allocation for multiple slices in mobile networks have been explored in
considerable detail in the existing literature, the suitability of the existing
mobile network architecture to support network slicing has not been analysed
adequately. We think the existing 5G System (5GS) architecture suffers from
certain limitations, such as a lack of slice isolation in its control plane.
This work focuses on the future evolution of the existing 5GS architecture from
a slicing perspective, especially that of its control plane, addressing some of
the limitations of the existing 5GS architecture. We propose a new network
architecture which enables efficient slicing in beyond 5G networks. The
proposed architecture results in enhanced modularity and scalability of the
control plane in sliced mobile networks. In addition, it also brings slice
isolation to the control plane, which is not feasible in the existing 5G
system. We also present a performance evaluation that confirms the improved
performance and scalability of the proposed system viz a viz the existing 5G
system.
