5G and Beyond Network Architecture and Wireline Network Convergence

The Performance of 5G Is Directly Impacted by Transport

- Overview

5G and beyond network architecture achieves wireless-wireline convergence by unifying fixed (fiber, DSL) and mobile access under a single, cloud-native 5G Core (5GC), using new functions like the Access Gateway Function (AGF) to integrate legacy systems, enabling unified subscriber management, network slicing, and simplified operations for a consistent, high-speed experience across all devices and access types, paving the way for future technologies like 6G. 

1. Key Architectural Components:

• Unified 5G Core (5GC): Replaces separate core networks for wireline and wireless, providing common service and policy management.
• Access Gateway Function (AGF): A new core function that bridges wireline access (fiber, DSL) to the 5GC, acting as a wireline equivalent to the Packet Gateway (PGW) for mobile.
• 5G Routing Gateway (5G RG): A customer premise device (CPE) that connects to the 5GC via wireline or wireless (Fixed Wireless Access - FWA), using SIMs for authentication, behaving like a 5G user.
• Cloud-Native & Virtualized: Network functions run as software on cloud infrastructure, allowing for flexibility, scalability, and efficient resource use.

2. How Convergence Works:

• Unified Access: The AGF allows broadband (wireline) users to access 5G services through their existing fiber or DSL connections, using the same 5G core as mobile users.
• Simplified Management: Operators manage all subscribers (mobile, fixed, FWA) from one core, reducing complexity and costs (CAPEX/OPEX).
• Network Slicing: Enables creation of dedicated virtual networks for specific services (e.g., low-latency gaming, IoT) that span both wireline and wireless.
• Control & User Plane Separation (CUPS): The AGF's architecture separates control and user data, allowing for flexible scaling and optimization.

3. Benefits for Operators & Users:

• Seamless Experience: Consistent services and SLAs across all access types (mobile, fixed, FWA).
• Future-Proofing: Supports new technologies like non-terrestrial networks (NTN) and satellite-to-device connectivity.
• Efficiency: Consolidates diverse legacy networks into one platform, reducing operational overhead.
• New Services: Enables advanced use cases in AI, robotics, IoT, and immersive experiences (metaverse).

4. Beyond 5G (6G & Future): 

The trend continues with 6G, focusing on even deeper integration, intelligence, and support for multimodal communication (combining 5G, AI, etc.) for hyper-connectivity. 

Convergence extends to the transport network, using programmable, packet-switched infrastructure (like Segment Routing) to unify all traffic.

- 5G Network Architecture and Wireline Network Convergence

5G network architecture converges wireless and wireline networks by using a single, unified 5G Core (5GC) and introducing the Access Gateway Function (AGF). 

This approach replaces separate legacy cores for wireline and wireless services with a common infrastructure, enabling a consistent user experience across different access methods and simplifying network management for operators. 

1. 5G network architecture:

• Converged core: Instead of using separate cores for wireless and wireline access, 5G utilizes a single, unified 5G core that can handle both.
• Cloud-native functions: The 5G core is built on cloud-native functions, allowing for greater flexibility and easier deployment.
• Control and user plane separation (CUPS): This architecture allows the control and user planes of the network to be separated and managed independently for optimized performance.
• Key elements: The architecture includes user terminals, radio access networks (which can include 4G LTE, 5G New Radio, and Wi-Fi), and the core network.

2. 5G wireline network convergence:

• Access Gateway Function (AGF): This new network function acts as a gateway between the wireline access network and the 5G core, making wireline connections appear as a 5G user to the core. It replaces the traditional Broadband Network Gateway (BNG).
• 5G Residential Gateway (5GRG): This is the device at the customer's premise that connects to the wireline network (like fiber or DSL) and communicates with the AGF in the 5G core. It can also function as a hybrid device, connecting to both wireline and 5G wireless networks.
• Unified management: With a converged core, operators can manage subscriber authentication, policy control, and other functions in a single system for both wireline and wireless customers, reducing complexity and cost.
• Consistent experience: The goal is to provide a consistent and seamless 5G experience, regardless of whether the user is connected via a fixed line or a mobile device.

- Traditional Mobile Network Domains

The four traditional domains of a mobile network are the device (user equipment), the Radio Access Network (RAN), the core network (CN), and the transport network. 

The device is the user's endpoint, the RAN connects devices to the network wirelessly, the core network coordinates the RAN and manages connectivity, and the transport network connects the RAN to the core network.