Network Digital Twin for 6G and Beyond: An End-to-End View Across Multi-Domain Network Ecosystems

TL;DR

This paper provides a comprehensive survey of Network Digital Twin (NDT) technology for 6G and beyond, covering multiple network domains, foundational technologies, and future research challenges.

Contribution

It is the first to offer an in-depth guide on NDT applications in RAN and 5GCORE+ and reviews key technologies and challenges for 6G+ networks.

Findings

NDT enables virtual network modeling and simulation for 6G+.

Survey covers RAN, transport, cloud, applications, NTNs, and quantum networks.

Identifies key challenges and future directions for NDT in 6G+.

Abstract

With the rapid development of technology, the number of smart mobile users is increasing, accompanied by growing demands from applications such as virtual/augmented reality (VR/XR), remote surgery, autonomous vehicles, and real-time holographic communications, all of which require high transmission rates and ultra-low latency in 6G and beyond networks (6G+). This poses enormous challenges in efficiently deploying large-scale networks, including network design, planning, troubleshooting, optimization, and maintenance, without affecting the user experience. Network Digital Twin (NDT) has emerged as a potential solution, enabling the creation of a virtual model that reflects the actual network, supporting the simulation of various network designs, applying diverse operating policies, and reproducing complex fault scenarios under real-world conditions. This motivate us for this study, where we provide a comprehensive survey of NDT in the context of 6G+, covering areas such as radio access networks (RAN), transport networks, 5G core networks and beyond (5GCORE+), cloud/edge computing, applications (blockchain, health system, manufacturing, security, and vehicular networks), non-terrestrial networks (NTNs), and quantum networks, from both academic and industrial perspectives. In particular, we are the first to provide an in-depth guide and usage of RAN and 5GCORE+ for NDT. Then, we provide an extensive review of foundation technologies such as transport networks, cloud/edge computing, applications, NTNs, and quantum networks in NDT. Finally, we discuss the key challenges, open issues, and future research directions for NDT in the context of 6G+.