Introduction to Access-Agnostic Core Networks
This whitepaper examines the design and implementation of an access-agnostic core network architecture that supports both 3GPP radio access technologies, such as E-UTRAN and 5G NR, as well as non-3GPP access methods, including Wi-Fi and wired connections. The motivation behind this approach is the increasing demand for high data rates across various environments, especially indoors, including high-density venues and residential areas, where operators aim to foster interworking between non 3GPP technologies and 3GPP technologies like 5G.
Non-3GPP Interworking: A Technical Overview
The concept of non-3GPP interworking is crucial for integrating diverse access technologies. This whitepaper provides a detailed explanation of how advanced traffic steering, switching, and splitting (ATSSS) mechanisms can be utilized to enhance data throughput and reliability. The 5G interworking scenarios extend beyond traditional LTE and WLAN offloading, incorporating a wide range of access technologies, categorized as trusted non-3GPP networks, untrusted non-3GPP networks, or wireline.
Dual-Access Capabilities and QoS Management
We explore the implications of dual-access capabilities for user equipment (UE) that can connect to both WLAN and 5G networks concurrently. This capability facilitates traffic offloading and enables more efficient QoS management. The paper discusses the technical requirements for ensuring secure and trusted access to the 5G core network (5GC) via WLAN, as well as the mechanisms for UEs that do not natively support 5G services.
Architectural Flexibility and Future-Proofing
The flexibility of the 5G system is a significant advantage, particularly in the context of service-based architecture (SBA), network slicing, and software-defined networking. We analyze how these paradigms contribute to the convergence of new and legacy technologies, providing a unified core network that can accommodate multiple access methods.
Future Directions
The paper also discusses the hierarchical structure of the 5G ecosystem, delineating the roles of the 5G core (5GC), radio access network (RAN), and user equipment (UE). We identify five primary access technologies to the 5GC, including WLAN, 5G NR, satellite technologies, wireline, and land mobile radio (LMR). Additionally, we address the complexities introduced by various UE categories and the implications for future technology evolution towards a unified 6G architecture.
Test and measurement aspects
Test and measurement techniques are essential for ensuring the proper implementation of interworking procedures and verifying compliance with standards. For non-3GPP interworking, these techniques include functional verification, protocol testing, and end-to-end quality assessments, primarily focusing on user equipment (UE) testing, which is also relevant for mobile networks. The whitepaper discusses the testing of UEs with interworking capabilities, covering signaling procedures, protocol scenarios, connection management, and application testing. Typically, a system simulator is used, supplemented by additional equipment for assessing spectral emissions, application quality, and security. We outline the test setup, requirements, basic connection configurations, and insights into end-to-end application testing, including mobility scenarios and audio or voice quality evaluations.
