Towards a 6G Ready Service-Based Access to Core Network Interface

The Service-Based Architecture introduced with the 5G core network has significantly improved the modularity, scalability, and service agility of mobile communication systems. Extending this architecture to the RAN is a promising development that could enhance connectivity service procedures, improve resource utilization, enable dynamic service deployment, and support a modular architecture. This paper provides a first analysis of a service-based interface between RAN and core compared to 5G's SCTP- and NGAP-based N2 interface. The paper includes a review of the SBA framework, highlighting recent research and advancements, as well as the potential advantages of a service-based RAN-core interface. Furthermore, a high level feature analysis demonstrates the potential for increased network efficiency and enhanced support, including an implementation and migration feasibility study. We propose a realistic servicebased RAN interface design and argue that applying SBA to the RAN interfaces can be a significant enhancement introduced with 6G.