2016年-数据局_IMT：《5G网络架构设计》白皮书英文版_25页_4mb

5G Network Architecture Design Summary

Introduction

The 5G network architecture is designed to meet the extreme requirements of high data rate, high traffic density, and ultra-low latency, while also enabling the "everything connected" vision. It introduces a more flexible and intelligent network structure, with a focus on network service convergence and on-demand service provision. The architecture is built upon core principles such as the separation of control and forwarding functions, modular design, and openness. This white paper proposes a novel 5G network architecture design, using logical function and platform deployment perspectives, and expands it into four-dimensional diagrams. It also highlights key 5G capabilities like network slicing, mobile edge computing, on-demand mobile network reconstruction, user-centered RAN, and network capacities exposure, and offers suggestions for standardization.

Main Challenges and Opportunities

Challenges

1. High KPI Requirements:

   • 5G aims to provide data rates from 100 Mbps to 1 Gbps anytime and anywhere.
   • It must maintain service continuity even at high speeds (up to 500 km/h).
   • It must support high traffic density (tens of Tbps/km²) and massive connection density (millions/km²).
   • It must achieve end-to-end latency below 1 ms under high reliability conditions.

2. Traditional Network Limitations:

   • The legacy network's centralized control and single data forwarding model may not support the high throughput and massive connections of 5G.
   • Current networks cannot meet the reliability and security needs of specific services like automated driving and industrial control.

Opportunities

1. Network and Service Convergence:

   • 5G enables network functions to be more flexible and tailored to user and vertical business needs.
   • This convergence allows for better user experience, efficient resource utilization, and new service growth points.

2. Infrastructure Advantages:

   • The "Full coverage and End-to-End" infrastructure allows for flexible and secure service deployment.
   • It supports third-party service platforms with isolated user data and dynamic resource scaling.

3. Technical Synergy:

   • The integration of mobile networks and the Internet fosters mutual technical interaction and innovation.
   • Cloud computing, virtualization, and softwarization are key enablers for 5G architecture design.

5G Network Architecture Design

The design of 5G network architecture is divided into system design and networking design.

1. 5G System Design

• Logical Diagram: Composed of three function planes: access plane, control plane, and forwarding plane.

  • Access Plane: Supports flexible RAN topologies using multi-BS coordination, multi-connection, and multi-RAT interworking.
  • Control Plane: Enables on-demand network partitioning and control functions such as radio resource management, mobility management, and session management.
  • Forwarding Plane: Offers distributed data forwarding and dynamic IP anchor configuration, supporting rich service chain capabilities.

• Function Diagram:

  • Management and Orchestration Layer: Includes user data, management and orchestration, and capabilities exposure functions. It supports network slicing and provides APIs for third-party access.
  • Network Control Layer: Centralized control functions for mobility, session, and security management, with dynamic resource scheduling based on orchestration layer instructions.
  • Network Resources Layer: Divided into access side (RAN) and network side (data forwarding, traffic optimization). RAN functions are split into Central Units (CUs) and Distributed Units (DUs).

2. 5G Networking Design

• Platform Diagram: Based on SDN/NFV technologies, the platform supports dynamic resource allocation and high-efficiency scheduling.

  • WAN Level: NFV orchestrator enables cross-data center function deployment and resource scheduling; SDN controller manages interconnection between data centers.
  • MAN Level and Below: Single data center is used for limited geographic areas with unified NFVI infrastructure and intra-data center resource scheduling.

• Networking Diagram:

  • Central Level: Responsible for control, management, and scheduling, deployed at national nodes.
  • Convergence Level: Carries control plane functions like mobility and session management, deployed at provincial levels.
  • Regional Level: Focuses on data forwarding, MEC, and service chain functions, deployed at city levels.
  • Access Level: Involves deployment of CUs and DUs, with flexible transport networks for low latency and high performance.

• Flexibility and Integration:

  • Networking levels are not strictly bound to geographic locations.
  • Operators can integrate functions across levels based on service requirements, traffic optimization, and user experience.

Typical 5G Network Capabilities

1. Network Slicing:

   • Provides end-to-end logical networks for specific services.
   • Includes slice management and slice selection.
   • Slice management involves template-based configuration, instantiation via NFV MANO, and execution with dynamic resource scaling and security.

2. Mobile Edge Computing (MEC):

   • Enables local service computing and data caching.
   • Key functions include:
     • Application and content within the pipe: Co-deploy MEC and gateway functions.
     • Dynamic service chaining: Flexibly set data forwarding paths.
     • Network assistance function: Optimize service based on network context and user profiles.

3. On-demand Mobile Network Reconstruction:

   • Supports flexible session management, mobility management, and security.
   • Session Management: Allows configuration based on device properties and service features.
   • Mobility Management: Enables dynamic adjustment of mobility levels for energy efficiency and service continuity.
   • Security: Offers flexible and open authentication, and secure infrastructure management.
   • Control Plane Retraction: Reduces complexity and enables dynamic function discovery and orchestration.

4. User-Centered RAN:

   • Shifts from "Base Station-Centered" to "User-Centric" design.
   • Includes flexible RAN control, context-aware service delivery, and customized access network.
   • Enables intelligent resource allocation and service prioritization based on user context and service demands.

5. Network Capacities Exposure:

   • Allows third-party access to network capabilities for service platform construction.
   • Supports dynamic resource scaling and secure user data isolation.

Standardization Suggestions

• Refine the design of 5G network architecture to guide industrial development.
• Focus on key technology directions such as SDN/NFV, network slicing, MEC, and user-centric RAN.
• Promote open interfaces and standardized protocols to enable flexible function invocation and service interworking.
• Support the integration of network functions across different levels and geographic hierarchies.

Conclusion

5G network architecture is a critical enabler for the future of connected services, offering enhanced flexibility, performance, and openness. It addresses the challenges of high data rate, traffic density, and latency, while creating new opportunities through network and service convergence. The design of 5G architecture is based on modular and platform-based principles, and the introduction of SDN/NFV and network slicing technologies will be pivotal in realizing the full potential of 5G. The architecture supports a wide range of services, from consumer mobile internet to industrial IoT, and aims to transform the network into an integrated, flexible, and open information service platform.

Main Contributors

• The white paper is contributed by industry experts and researchers who have focused on 5G network design, standardization, and technological innovation. Their insights provide a comprehensive view of 5G architecture evolution and its impact on future communication systems.