6G Frontiers

About the Authors xv Preface xvii Acknowledgments xxi Acronyms xxiii Part I Introduction 1 1 Evolution of Mobile Networks 3 1.1 Introduction 3 1.2 6G Mobile Communication Networks 5 1.2.1 6G as Envisioned Today 5 1.2.2 6G Development Timeline 6 2 Key Driving Trends Toward 6G 9 2.1 Introduction 9 2.2 Expansion of IoT toward IoE 11 2.3 Massive Availability of Small Data 12 2.4 Availability of Self-Sustaining Networks 13 2.5 Convergence of Communications, Computing, Control, Localization, and Sensing (3CLS) 14 2.6 Zero Energy IoT 15 2.7 Advancement of Communication Technologies 16 2.8 Gadget-Free Communication 17 2.9 Increasing Elderly Population 18 3 6G Requirements 21 3.1 6G Requirements/Vision 21 3.2 Further-Enhanced Mobile Broadband (FeMBB) 23 3.2.1 Enabling 6G Applications 23 3.2.2 Enabling 6G Technologies 23 3.3 Ultramassive, Machine-Type Communication 24 3.3.1 Enabling 6G Applications 24 3.3.2 Enabling 6G Technologies 24 3.4 Extremely Reliable Low Latency Communication 25 3.4.1 Enabling 6G Applications 25 3.4.2 Enabling 6G Technologies 26 3.5 Extremely Low Power Communication 26 3.5.1 Enabling 6G Applications 27 3.5.2 Enabling 6G Technologies 27 3.6 Long Distance and High Mobility Communication 27 3.6.1 Enabling 6G Applications 27 3.6.2 Enabling 6G Technologies 27 3.7 High Spectrum Efficiency 28 3.7.1 Enabling 6G Applications 28 3.7.2 Key Enabling 6G Technologies 29 3.8 High Area Traffic Capacity 29 3.8.1 Enabling 6G Applications 29 3.8.2 Enabling 6G Technologies 29 3.9 Mobile Broadband and Low Latency (MBBLL) 29 3.9.1 Enabling 6G Applications 30 3.9.2 Enabling 6G Technologies 30 3.10 Massive Broadband Machine-Type Communications 30 3.10.1 Enabling 6G Applications 31 3.10.2 Enabling 6G Technologies 31 3.11 Massive Low Latency Machine-type Communications (mLLMT) 31 3.11.1 Enabling 6G Applications 32 3.11.2 Enabling 6G Technologies 32 3.12 AI-Assistive Extreme Communications 32 3.12.1 Enabling 6G Applications 32 3.12.2 Enabling 6G Technologies 33 4 Key 6G Technologies 35 4.1 Radio Network Technologies 35 4.1.1 Beyond Sub-6 GHz toward THz Communication 35 4.1.2 Nonterrestrial Networks Toward 3D Networking 37 4.2 AI/ML/FL 39 4.3 DLT/Blockchain 42 4.4 Edge Computing 44 4.5 Quantum Communication 47 4.6 Other New Technologies 49 4.6.1 Visible Light Communications 49 4.6.2 Large Intelligent Surfaces 50 4.6.3 Compressive Sensing 50 4.6.4 Zero-touch Network and Service Management 51 4.6.5 Efficient Energy Transfer and Harvesting 52 Part II Architectural Directions 55 5 6G Architectural Visions 57 5.1 Evolution of Network Architecture 57 5.2 Intelligent Network of Subnetworks 58 5.3 A Greener Intelligent Network 60 5.4 Cybertwin-based Network Architecture 61 6 Zero-Touch Network and Service Management 63 6.1 Introduction 63 6.2 Need of Zero-Touch Network and Service Management 64 6.3 Overview of Zero Touch Network and Service Management 65 6.3.1 ZSM Architecture Principles 65 6.3.2 ZSM Architecture Requirements 66 6.3.2.1 Nonfunctional Requirements 66 6.3.2.2 Functional Requirements 66 6.3.2.3 Security Requirements 67 6.4 ZSM Reference Architecture 68 6.4.1 Components 68 6.4.1.1 Management Services 69 6.4.1.2 Management Functions 70 6.4.1.3 Management Domains 70 6.4.1.4 The E2E Service Management Domain 70 6.4.1.5 Integration Fabric 70 6.4.1.6 Data Services 70 6.4.2 ZSM Interfaces 70 6.4.2.1 Domain Data Collection 70 6.4.2.2 Domain Analytics 71 6.4.2.3 Domain Intelligence 71 6.4.2.4 Domain Orchestration 71 6.4.2.5 Domain Control 71 6.4.2.6 E2E Data Collection 71 6.4.2.7 E2E Analytics 71 6.4.2.8 E2E Intelligence 72 6.4.2.9 E2E Orchestration 72 6.5 Importance of ZSM for 5G and Beyond 72 7 Edge AI 73 7.1 Introduction 73 7.2 Benefits of Edge AI 75 7.3 Why Edge AI Is Important? 76 7.4 Building Blocks for Edge AI 77 7.4.1 Edge Computing 77 7.4.2 Support for Advanced Edge Analytics 78 7.4.3 Edge Inference and Edge Training 80 7.5 Architectures for Edge AI networks 81 7.5.1 End-to-End Architecture for Edge AI 81 7.5.2 Decentralized Edge Intelligence 81 7.6 Level of Edge AI 83 7.7 Future Cloud Computing Perspective 85 7.7.1 Resource Management 85 7.7.2 Energy and Operational Constraints 86 7.7.3 Security, Trust, and Privacy 86 7.7.4 Intermittent Connectivity 87 7.8 Role of Edge AI in 6G 88 7.8.1 Communication and Computation with Human-in-the-Loop 88 7.8.2 Critical but Conflicting Actors and Applications 89 7.8.3 Edge AI and Emerging Technologies 89 7.8.4 Technology Meets Business 90 Acknowledgment 91 8 Intelligent Network Softwarization 93 8.1 Network Softwarization 93 8.2 Intelligent Network Softwarization 95 8.2.1 Service Function Chaining 95 8.2.2 Programmable Data Planes 96 8.2.3 In-Network Computing 97 9 6G Radio Access Networks 99 9.1 Key Aspects and Requirements 99 9.1.1 Flexibility 100 9.1.2 Massive Interconnectivity 101 9.1.3 Energy Efficiency 102 9.2 Aerial Radio Access Networks 103 9.3 AI-enabled RAN 108 9.4 Open RAN 112 Part III Technical Aspects 115 10 Security and Privacy of 6G 117 10.1 Introduction 117 10.2 Evolution of Mobile Security 118 10.3 6G Security Requirements 119 10.3.1 6G Security Vision and KPIs 119 10.4 Security Threat Landscape for 6G Architecture 121 10.4.1 Intelligence Radio and RAN-Core Convergence 123 10.4.2 Edge Intelligence and Cloudification of 6G Era 124 10.4.3 Specialized 6G Networks 125 10.4.4 Intelligence Network Management and Orchestration 125 10.4.5 Consumer End (Terminals and Users) 128 10.5 Security Challenges with 6G Applications 129 10.5.1 UAV-based Mobility 130 10.5.2 Holographic Telepresence 130 10.5.3 Extended Reality 131 10.5.4 Connected Autonomous Vehicles (CAV) 131 10.5.5 Smart Grid 2.0 132 10.5.6 Industry 5.0 133 10.5.7 Digital Twin 133 10.6 Security Impact on New 6G Technologies 134 10.6.1 Distributed Ledger Technology (DLT) 134 10.6.1.1 Threat Landscape 135 10.6.1.2 Possible Solutions 137 10.6.2 Quantum Computing 138 10.6.2.1 Threat Landscape 138 10.6.2.2 Possible Solutions 139 10.6.3 Distributed and Scalable AI/ML 140 10.6.3.1 Threat Landscape 141 10.6.3.2 Possible Solutions 142 10.6.4 Physical-Layer Security 142 10.6.4.1 TeraHertz Technology 142 10.6.4.2 Threat Landscape 143 10.6.4.3 Possible Solutions 143 10.6.4.4 Visible Light Communication Technology 144 10.6.4.5 Threat Landscape 144 10.6.4.6 Possible Solutions 144 10.6.4.7 Reconfigurable Intelligent Surface 145 10.6.4.8 Threat Landscape 145 10.6.4.9 Possible Solutions 145 10.6.4.10 Molecular Communication (MC) 145 10.6.4.11 Threat Landscape 145 10.6.4.12 Possible Solutions 146 10.7 Privacy 146 11 Resource Efficient Networks 151 11.1 Energy-Efficient 6G Network Management 152 11.2 Energy-efficient Security 156 11.3 Efficient Resource Management 158 Acknowledgement 161 12 Harmonized Mobile Networks and Extreme Global Network Coverage 163 12.1 Harmonized Mobile Networks 163 12.2 Extreme Global Network Coverage 171 12.3 Limitations and Challenges 178 13 Legal Aspects and Standardization of 6G Networks 181 13.1 Legal Aspects 181 13.1.1 Recent Developments of Legal Frameworks 182 13.2 6G Standardization Efforts 183 13.2.1 European Telecommunications Standards Institute 183 13.2.2 Next Generation Mobile Networks (NGMN) Alliance 185 13.2.3 Alliance for Telecommunications Industry Solutions (ATIS) 185 13.2.4 Next G Alliance 185 13.2.5 5G Automotive Association 186 13.2.6 Association of Radio Industries and Businesses (ARIB) 186 13.2.7 5G Alliance for Connected Industries and Automation (5G-ACIA) 186 13.2.8 Third-Generation Partnership Project (3GPP) 186 13.2.9 International Telecommunication Union-Telecommunication (ITU-T) 187 13.2.10 Institute of Electrical and Electronics Engineers 187 13.2.11 Other SDOs 187 13.2.11.1 Inter-American Telecommunication Commission (CITEL) 187 13.2.11.2 Canadian Communication Systems Alliance (CCSA) 187 13.2.11.3 Telecommunications Standards Development Society, India (TSDSI) 188 13.2.11.4 Telecommunications Technology Association (TTA) 188 13.2.11.5 Telecommunication Technology Committee (TTC) 188 Part IV Applications 189 14 6G for Healthcare 191 14.1 Evolution of Telehealth 191 14.2 Toward Intelligent Healthcare with 6G 192 14.3 Personalized Body Area Networks 193 14.4 XR for Healthcare Applications 194 14.5 Role of Blockchain in Medical Applications 195 14.6 Security and Privacy Aspects of 6G Healthcare Applications 196 15 Smart Cities and Society 5.0 197 15.1 Preliminaries of Smart Cities 197 15.2 6G for Smart Citizen 199 15.3 6G for Smart Transportation 201 15.4 6G for Smart Grid 204 15.5 6G for Supply Chain Management 207 15.6 6G for Other Smart Scenarios 209 Acknowledgement 210 16 Industrial Automation 211 16.1 Introduction 211 16.1.1.1 Motivations Behind the Evolution of Industry 5.0 212 16.2 Background of Industry 5.0 214 16.2.1 Definitions 215 16.2.2 Additional Features of Industry 5.0 216 16.2.2.1 Smart Additive Manufacturing 216 16.2.2.2 Predictive Maintenance 216 16.2.2.3 Hyper-Customization 217 16.2.2.4 Cyber Physical Cognitive Systems 218 16.3 Applications in Industry 5.0 218 16.3.1 Cloud Manufacturing 218 16.3.2 Digital Twins 220 16.3.3 Cobots (Collaborative Robots) 220 16.3.4 Supply Chain Management 221 16.3.5 Manufacturing/Production 222 16.4 Role of 6G in Industry 5.0 223 16.4.1 Internet of Everything 224 16.4.1.1 Big Data Analytics 224 16.4.1.2 Blockchain 225 16.4.2 Edge Computing 225 16.4.2.1 Other Enabling Technologies 226 17 Wild Applications 229 17.1 Introduction 229 17.2 Metaverse 229 17.3 Deep-Sea Explorations 231 17.4 Space Tourism 232 Acknowledgement 235 Part V Conclusion 237 18 Conclusion 239 Bibliography 241 Index 293