The upcoming Sixth Generation (6G) mobile communications system envisions supporting a variety of use cases with differing characteristics, e.g., very low to extremely high data rates, diverse latency needs, ultra massive connectivity, sustainable communications, ultra-wide coverage etc. To accommodate these diverse use cases, the 6G system architecture needs to be scalable, modular, and flexible; both in its user plane and the control plane. In this paper, we identify some limitations of the existing Fifth Generation System (5GS) architecture, especially that of its control plane. Further, we propose a novel architecture for the 6G System (6GS) employing Software Defined Networking (SDN) technology to address these limitations of the control plane. The control plane in existing 5GS supports two different categories of functionalities handling end user signalling (e.g., user registration, authentication) and control of user plane functions. We propose to move the end-user signalling functionality out of the mobile network control plane and treat it as user service, i.e., as payload or data. This proposal results in an evolved service-driven architecture for mobile networks bringing increased simplicity, modularity, scalability, flexibility and security to its control plane. The proposed architecture can also support service specific signalling support, if needed, making it better suited for diverse 6GS use cases. To demonstrate the advantages of the proposed architecture, we also compare its performance with the 5GS using a process algebra-based simulation tool.

翻译：下一代第六代（6G）移动通信系统设想支持多种具有不同特性的用例，例如从极低到极高的数据速率、多样化的时延需求、超大规模连接、可持续通信、超广覆盖等。为适应这些多样化用例，6G系统架构需要在用户面和控制面均具备可扩展性、模块化和灵活性。本文识别出现有第五代系统（5GS）架构的一些局限性，尤其是其控制面的局限性。进一步，我们提出一种采用软件定义网络（SDN）技术的新型6G系统（6GS）架构，以解决控制面的这些局限。现有5GS的控制面支持两类不同功能：处理终端用户信令（例如用户注册、认证）和控制用户面功能。我们建议将终端用户信令功能移出移动网络控制面，并将其视为用户服务，即作为载荷或数据处理。这一提议催生了一种演进的面向服务的移动网络架构，为其控制面带来更高的简洁性、模块化、可扩展性、灵活性和安全性。该架构还能在需要时支持特定服务的信令支持，从而更好地适应多样化的6GS用例。为展示所提架构的优势，我们还采用基于进程代数的仿真工具，将其性能与5GS进行了比较。