Mobile Communications Systems Development

Rajib Taid is currently Deputy General Manager (Information Technology) for BCPL, India. He has over 20 years of experience working with and in government agencies and private corporations. His competencies range from mobile communications software research and development to managing multiple technology domains and platforms.

• About the Author xivPreface xvAcknowledgments xviiiList of Abbreviations xix1 Introduction 1Part I Network Architectures, Standardization, Protocols, and Functions 32 Network Architectures, Standardizations Process 52.1 Network Elements and Basic Networks Architectures 52.1.1 GSM (2G) Network Architecture 62.1.2 General Packet Radio Service (GPRS-2.5G) Network Architecture 72.1.3 Universal Mobile Telecommunications System (3G) Network Architecture 72.1.4 LTE (4G) Network Architecture 82.1.5 GSM, UMTS, LTE, and 5G Network Elements: A Comparison 92.1.6 Circuit Switched (CS) vs Packet Switched (PS) 92.2 Mobile Communication Network Domains 102.2.1 AN Domain 102.2.2 Core Network (CN) Domain 112.2.3 Network Domains and Its Elements 112.2.4 Example: End-to-End Mobile Network Information Flow 122.2.5 Example: GSM MO Call 132.3 Mobile Communications Systems Evolutions 142.3.1 Evolutions of Air Interface 142.3.2 Evolutions of 3GPP Networks Architectures 162.4 Mobile Communications Network System Engineering 192.4.1 Mobility Management 192.4.2 Air Interface Management 202.4.3 Subscribers and Services Management 202.4.4 Security Management 202.4.5 Network Maintenance 202.5 Standardizations of Mobile Communications Networks 212.5.1 3rd Generation Partnership Project (3GPP) 212.5.2 3GPP Working Groups 212.5.3 3GPP Technical Specification and Technical Report 222.5.4 Stages of a 3GPP Technical Specification 222.5.5 Release Number of 3GPP Technical Specification 222.5.6 3GPP Technical Specification Numbering Nomenclature 232.5.7 Vocabulary of 3GPP Specifications 242.5.8 Examples in a 3GPP Technical Specification 242.5.9 Standardization of Technical Specifications by 3GPP 242.5.10 Scope of 3GPP Technical Specification (TS) 242.5.11 3GPP TS for General Description of a Protocol Layer 252.5.12 3GPP TS Drafting Rules: Deriving Requirements 252.5.13 Download 3GPP Technical Specifications 252.5.14 3GPP Change Requests 262.5.15 Learnings from 3GPP Meetings TDocs 262.6 3GPP Releases and Its Features 26Chapter Summary 273 Protocols, Interfaces, and Architectures 293.1 Protocol Interface and Its Stack 293.1.1 Physical Interface 303.1.2 Logical Interface 303.1.3 Logical Interfaces’ Names and Their Protocol Stack 333.1.4 Examples of Logical Interface and Its Protocol Layers 353.2 Classifications of Protocol Layers 363.2.1 Control Plane or Signaling Protocols 363.2.2 User Plane Protocols 383.3 Grouping of UMTS, LTE, and 5G Air Interface Protocol Layers 393.3.1 Access Stratum (AS): UMTS UE – UTRAN; LTE UE – E-UTRAN;5G UE - NG-RAN 393.3.2 Non-Access Stratum: UMTS UE – CN, LTE UE – EPC; 5G UE-Core 413.4 Initialization of a Logical Interface 423.5 Protocol Layer Termination 433.6 Protocol Sublayers 433.7 Protocol Conversion 443.8 Working Model of a 3GPP Protocol Layer: Services and Functions 453.9 General Protocol Model Between RAN and CN (UMTS, LTE, 5G) 463.10 Multiple Transport Networks, Protocols, and Physical Layer Interfaces 473.11 How to Identify and Understand Protocol Architectures 493.11.1 Identifying a Logical Interface, Protocol Stack, and Its Layers 493.11.2 Identification of Technical Requirements Using Interface Name 513.12 Protocol Layer Procedures over CN Interfaces 513.12.1 Similar Functions and Procedures over the CN Interfaces 523.12.2 Specific Functions and Procedures over the CN Interfaces 53Chapter Summary 544 Encoding and Decoding of Messages 554.1 Description and Encoding/Decoding of Air Interface Messages 554.1.1 Encoding/Decoding: Air Interface Layer 3 Messages 564.1.2 Encoding/Decoding: LTE and 5G NR Layer 2: RLC Protocol 604.1.3 Encoding/Decoding: LTE and 5G NR Layer 2: MAC Protocol 604.1.4 CSN.1 Encoding/Decoding: GPRS Layer 2 Protocol (RLC/MAC) 604.1.5 ASN.1 Encoding/Decoding: UMTS, LTE, and 5G NR Layer 3 Protocol 614.1.6 Direct/Indirect Encoding Method 624.1.7 Segmented Messages over the Air Interface 634.1.8 Piggybacking a Signaling Message 634.2 Encoding/Decoding of Signaling Messages: RAN and CN 64Chapter Summary 655 Network Elements: Identities and Its Addressing 675.1 Network Elements and Their Identities 675.2 Permanent Identities 685.3 Temporary Identities Assigned by CN 695.3.1 GSM System Temporary Identities 695.3.2 GPRS System Temporary Identities 695.3.3 LTE/EPS System Temporary Identities 705.4 Temporary Identities Assigned by RAN: RNTI 725.5 Usages of Network Identities 735.6 Native and Mapped Network Identities 735.7 LTE UE Application Protocol Identity 75Chapter Summary 766 Interworking and Interoperations of Mobile Communications Networks 776.1 Requirements and Types of Interworking 776.2 Interworking Through Enhanced Network Elements 786.2.1 Interworking for Voice Call Through IMS: VoLTE 796.2.1.1 IP Multimedia Subsystem (IMS) 806.2.1.2 UE Registration and Authentication 816.2.2 Interworking for VoLTE Call Through LTE/EPS: SRVCC 836.2.3 Interworking for Voice Call Through LTE/EPS: CSFB 856.3 Interworking Through Legacy Network Elements 886.4 Interworking Between LTE/EPS and 5G Systems 896.5 Interoperations of Networks: LTE/EPS Roaming 906.5.1 Roaming Through Interoperations of Enhanced Networks Elements 906.5.2 Roaming Through Interoperations of Legacy Networks Elements 926.6 UE Mode of Operation 926.7 Function of E-UTRAN in a VoLTE Call 95Chapter Summary 957 Load Balancing and Network Sharing 977.1 Core Network Elements Load Balancing 977.1.1 Identification of NAS Node: NRI and Its Source 997.1.2 NAS Node Selection Function 997.2 Network Sharing 1027.2.1 GSM/GPRS/LTE RAN Sharing Through MOCN Feature 1037.2.2 5G NG‐RAN Sharing Through MOCN Feature (Release 16) 109Chapter Summary 1108 Packets Encapsulations and Their Routing 1118.1 User Data Packets Encapsulations 1118.1.1 Packets Encapsulations at the CN and RAN 1128.1.1.1 GPRS Tunneling Protocol ( GTP) 1128.1.1.2 GTP Functions 1128.1.1.3 GTP User Plane PDU: G-PDU 1138.1.1.4 GTP Control Plane PDU 1148.1.1.5 Example: GTP and Packet Encapsulations at LTE EPC 1158.1.2 Packet Encapsulations over Air Interface 1158.2 IP Packet Routing in Mobile Communications Networks 1168.3 IP Header Compression and Decompression 117Chapter Summary 1199 Security Features in Mobile Communications Networks 1219.1 A Brief on the Security Architecture: Features and Mechanisms 1219.2 Security Features and Its Mechanisms 1239.3 GSM Security Procedures 1269.4 UMTS, LTE, and 5G: AS and NAS Layer Security Procedures 1279.5 Security Contexts 1309.6 Security Interworking 130Chapter Summary 132Part II Operations and Maintenances 13310 Alarms and Faults Managements 13510.1 Network Elements Alarm and Its Classifications 13510.2 Sources of Abnormal Events and Alarms 13610.3 Identifying Sources of Alarms from 3GPP TSs 13610.3.1 Abnormal Conditions 13610.3.2 Protocol Layer Error Handling 13710.3.3 Abnormal Conditions Due to Local Errors 13810.4 Design and Implementation of an Alarm Management System 13810.4.1 Design and Components of an Alarm 13910.4.2 Alarm Application Programming Interfaces (APIs) 13910.4.3 Alarm Database 13910.5 Alarm Due to Protocol Error 14010.5.1 Sample Protocol Error Alarm Description 14210.6 Alarm Due to Abnormal Conditions 14210.6.1 Normal Scenario 14310.6.2 Abnormal Scenario 14310.6.3 Sample Alarm Description 14410.6.4 Sample Alarm Generation 14510.6.5 Sample Protocol Error Alarm Generation 14510.7 How to Troubleshoot Protocol Error Using the Alarm Data 146Chapter Summary 14611 Performance Measurements and Optimizations of Mobile Communications Networks 14711.1 Counters for Performance Measurements and Optimizations 14711.2 Performance and Optimizations Management System 14911.3 Key Performance Indicator (KPI) 15011.3.1 What Is a KPI? 15011.3.2 KPI Domains 15011.3.3 KPI for Signaling or Control Plane 15211.3.4 KPI for User or Data Plane 15311.3.5 KPI Categories 15411.3.6 KPI Evaluation Steps 15511.3.7 Troubleshooting and Improving KPI 15611.3.8 Components of a KPI Definition 157Chapter Summary 15712 Troubleshooting of Mobile Communications Networks Issues 15912.1 Air Interface-Related Issues 15912.1.1 Drive Test, Data Collection, and Its Analysis 16012.2 Debugging Issues with IP-Based Logical Interface 16012.2.1 IP Protocol Analyzer 16112.2.2 Network/Application Throughput Issue 16112.2.3 Switch Port Mirroring 16112.3 Conformance Testing Issues 16212.3.1 Example: Mobile Device (MS)/User Equipment (UE) Conformance Test 16312.3.2 Example: Location Area Update Request 16312.4 Interoperability Testing (IOT) Issues 16412.5 Interworking Issues 16512.6 Importance of Log/Traces and Its Collections 16612.7 Steps for Troubleshooting 167Chapter Summary 170Part III Mobile Communications Systems Development 17113 Core Software Development Fundamentals 17313.1 A Brief on Software Development Fundamentals 17313.1.1 Requirements Phase 17413.1.2 Design 17413.1.3 Implementation 17513.1.4 Integration and Testing 17513.1.5 Operation and Maintenance 17513.2 Hardware Platforms: Embedded System, Linux Versus PC 17613.2.1 System Development Using Embedded System Board 17613.2.2 System Development Using Multicore Hardware Platform 17713.2.2.1 What Is a Core? 17813.2.2.2 Network Element Development Using Multicore Platform 17813.2.2.3 Runtime Choices of Multicore Processor 17813.2.2.4 Software Programming Model for Multicore Processor 17913.3 Selecting Software Platforms and Features 17913.3.1 Selecting Available Data/Logical Structures 18013.3.1.1 Advanced Data Structures 18013.3.1.2 How Data Structure Affects the Application’s Performance 18013.3.2 Selecting an Operating System Services/Facilities 18113.3.2.1 Advance Features of Operating System: IPC 18113.4 Software Simulators for a Mobile Communications Network 18413.5 Software Root Causes and Their Debugging 18513.5.1 Incorrect Usages of Software Library System Calls/APIs 18513.5.2 Incorrect Usages of System Resources 18513.5.3 Bad Software Programming Practices 18513.6 Static Code Analysis of Software 18613.7 Software Architecture and Software Organization 18613.8 System and Software Requirements Analysis 18813.9 Software Quality: Reliability, Scalability, and Availability 18813.9.1 Reliability 18813.9.2 Scalability 18813.9.3 Availability 188Chapter Summary 18914 Protocols, Protocol Stack Developments, and Testing 19114.1 Components of a 3GPP Protocol TS 19114.2 3GPP Protocol Layer Structured Procedure Description 19314.3 Protocol Layer Communications 19414.3.1 Layer-to-Layer Communication Using Service Primitives 19514.3.2 Layer-to-Layer Communication: SAP 19614.3.3 Peer-to-Peer Layer Communication: PDU and Service Data Unit (SDU) 19714.3.4 Types of PDU 19814.3.5 Formats of PDU 19814.4 Air Interface Message Format: Signaling Layer 3 19814.4.1 A Brief on the Air Interface Layer 3 Protocol Stack 19814.4.2 Classification of Layer 3 Messages 19914.4.3 Layer 3 Protocol Header: Signaling Message Format 20014.4.4 Layer 3 Protocol Header: Protocol Discriminator 20214.4.5 Layer 3 Protocol Header: GSM, GPRS Skip Indicator 20214.4.6 Layer 3 Protocol Header: GSM, GPRS Transaction Identifier 20414.4.7 Layer 3 Protocol Header: LTE/EPS Bearer Identity 20414.4.8 Layer 3 Protocol Header: 5GSM PDU Session Identity 20414.4.9 Constructing a Layer 3 Message 20414.4.10 Security Protected LTE/EPS and 5G NAS Layer MM Messages 20514.4.11 Layer 3 Protocol Layer’s Message Dump 20714.5 Air Interface Message Format: Layer 2 20714.6 RAN – CN Signaling Messages 20814.6.1 Protocol Layer Elementary Procedure 20814.6.2 Types and Classes of EPs 21014.6.3 EPs Code 21014.6.4 Criticality of IE 21114.6.5 Types of Protocol Errors and Its Handling 21114.6.6 Choices of Triggering Message 21214.6.7 Message Type 21214.6.8 Message Description 21214.6.9 Example: LTE/EPS S1 Interface: S1 Setup Procedure 21314.7 Modes Operation of a Protocol Layer 21314.8 Example of a Protocol Primitive and PDU Definition 21514.9 Example of a Protocol Layer Frame Header Definition 21614.10 Examples of System Parameters 21614.11 Examples of Protocol Information Elements and Its Identifier 21714.12 3GPP Release Specific Changes Implementation 21814.13 Examples of Protocol Messages Types 21914.14 Protocol Layer Timer Handling 21914.15 Protocol Layer Development Using State Machine 22214.16 Protocol Layer Development Using Message Passing 22414.17 Protocol Layer Data and its Types 22514.18 Protocol Layer Control and Configuration 22614.19 Protocol Context Information 22714.20 Protocol Layer Message Padding 22814.21 Device Driver Development 22914.22 Guidelines for Protocol Stack/Layer Development 23014.23 Software Profiling, Tools and Performance Improvement 23114.24 Protocol Stack Testing and Validation 231Chapter Summary 23315 Deriving Requirements Specifications from a TS 23515.1 3GPP Protocol Layer Procedures 23515.1.1 LTE UE Mode of Operation Requirements 23615.1.2 LTE UE ATTACH Procedure Requirements 23615.1.3 LTE UE DETACH Procedure Requirements 23715.1.4 LTE UE Tracking Area Update Procedure Requirements 23715.2 3GPP System Feature Development Requirements 23815.2.1 Identification of System/Network Elements Interfaces Changes 23815.2.2 Identifications of Impacts on Performance 23815.2.3 Identifications of Impacts on Feature Management 23915.2.4 Identification of Interworking Requirements with Existing Features 23915.2.5 Charging and Accounting Aspects 23915.3 Example Feature: Radio Access Network Sharing 23915.3.1 Effects on Network Elements 23915.3.2 Effects on Logical Interfaces 24015.3.3 Selection of Core Network Operator: PLMN Id 24115.4 Example: Interworking/Interoperations 24215.4.1 Circuit-Switched Fall Back (CSFB) 24215.4.2 Single Radio Voice Call Continuity (SRVCC) 24315.5 3GPP System Feature and High-Level Design 244Chapter Summary 245Part IV 5G System and Network 24716 5G Network: Use Cases and Architecture 24916.1 5G System (5GS) Use Cases 24916.1.1 Enablers and Key Principles of 5GS Use Cases 25016.1.2 Other Enablers in 5G System 25316.2 Support of Legacy Services by 5G System 25316.3 5G System Network Architecture 25416.3.1 3GPP Access Architecture 25416.3.2 Non-3GPP Access Architecture 25616.4 5G System NG–RAN/gNB Logical Architecture 25616.5 5GC System Architecture Elements 25916.6 5G System Deployment Solutions 26016.6.1 E–UTRA–NR Dual Connectivity (EN–DC) for NSA Deployment 26116.7 5G System and LTE/EPS Interworking 26516.7.1 RAN-Level Interworking 26516.7.2 Core Network (CN) Level Interworking: N26 Interface 26516.7.2.1 Single Registration Mode with N26 Interface 26616.7.2.2 Dual Registration Mode: Without N26 Interface 26616.8 5G System Native and Mapped Network Identities 26816.8.1 Mobility Area Identifiers 26816.8.2 UE/Subscriber Permanent Identifiers 26916.8.3 Core Network Identifiers 26916.8.4 RAN Identifiers 26916.8.5 Core Network Temporary Identities 27016.9 5G System Network Slicing 27016.9.1 Identities for a Network Slice 27116.9.2 Impacts of Network Slicing Feature 27316.10 Management and Orchestration (MANO) of 5G Network 27816.11 5G System Security 28016.11.1 UE Authentication Frameworks and Methods 28016.11.2 Primary Authentication and Secondary Authentication 28216.11.3 Key Hierarchy and Authentication Vector 28216.11.4 New Security Requirements in 5G System 28316.11.5 Subscriber Identities/Privacy Protection 286Chapter Summary 28717 Introduction to GSM, UMTS, and LTE Systems Air Interface 28917.1 Air Interfaces Protocol Architectures 28917.2 Protocol Sublayers 29017.3 Control Plane and User Plane Protocols 29117.4 Protocols Domains Classifications 29117.5 Access Stratum and Non-access Stratum 29117.6 Message Formats 29217.7 Security Over the Air Interface 29317.8 Piggybacking for Reduction of Signaling Overhead 29317.8.1 Examples Piggybacking of Signaling Messages 293Chapter Summary 29418 5G NR Air Interface: Control Plane Protocols 29518.1 NR Control Plane Protocol Layers 29518.2 Session Management (5G SM) Layer 29618.2.1 Procedures of 5G SM Layer 29718.2.2 PDU Session Types 29818.2.3 PDU Session Service Continuity (SSC) 29918.2.4 PDU Sessions for Network Slices 30018.2.5 Session Management (SM) Layer States 30118.3 Quality of Service (5G QoS) 30118.3.1 LTE/EPS QoS Model: EPS Bearer 30118.3.2 5GS QoS Model: QoS Flow 30118.3.3 GTP-U Plane Tunnel for PDU Session 30218.3.4 Service Data Flow and PCC Rule 30218.3.5 Binding of Service Data Flow 30318.3.6 QoS Profile and QFI 30318.3.7 QoS Rule and QRI 30518.3.8 Mapping QoS Flow to Data Radio Bearer 30518.3.9 Downlink Data Flow Through GTP-U Plane Tunnels 30718.4 Mobility Management (5G MM) Layer 30818.4.1 Mobility Area Concepts and Identifiers 30818.4.2 Requirements of Mobility Management Functions 31318.4.3 Functions and Procedures of 5G MM Layer 31418.4.4 Mobility Management Layer States 31518.4.5 Connection Management (CM) and Service Request 31618.4.6 Mobility Pattern of UE 31718.5 RRC Layer 31718.5.1 Functions and Procedures of RRC Layer 31718.5.2 System Information (SI) Broadcast 31818.5.3 RRC Layer States 31918.5.4 RRC INACTIVE State 32018.5.5 Mobility of UE 32618.5.5.1 UE Mobility in RRC IDLE State 32618.5.5.2 UE Mobility in RRC INACTIVE State 32618.5.5.3 UE Mobility in RRC CONNECTED State 32718.5.6 Admission Control 332Chapter Summary 33419 5G NR Air Interface 33519.1 NR User Plane Protocol Layers 33519.2 SDAP Layer 33619.3 PDCP Layer 33619.4 RLC Layer 34019.5 MAC Layer 34219.5.1 Functions and Procedures 34219.5.2 Scheduling Procedure 34419.5.3 Random Access Procedure 34619.5.4 Error Correction Through HARQ Procedure 35119.5.5 Buffer Status Reporting (BSR) Procedure 35219.5.6 Scheduling Request (SR) Procedure 35319.5.7 Low Latency in the NR Due to Configured Scheduling 35319.5.8 MAC Layer PDU and Header Structures 35419.5.9 How MAC Layer Ensures Low‐Latency Requirements 35619.5.10 Channel Structures in NR 35719.6 Physical Layer 35919.6.1 Principles of Transmissions and Its Directions 36019.6.2 Physical Layer Functions, Procedures, and Services 36019.6.3 OFDM Symbol 36319.6.4 NR Frame and Slot Format 36419.6.4.1 Subcarrier Spacing (SCS)/Numerologies (μ) 36419.6.4.2 Slots per NR Frame and Subframe 36419.6.4.3 Slot Formats in TDD Mode 36619.6.4.4 Dynamic TDD 36719.6.5 Resource Grid and Resource Block 36819.6.5.1 Control Resource Set (CORESET) 36919.6.5.2 Common Resource Blocks (CRB) 37019.6.5.3 Physical Resource Block (PRB) 37019.6.5.4 Virtual Resource Block (VRB) 37019.6.5.5 Interleaved and Non‐interleaved PRB Allocation 37019.6.5.6 PRB Bundling and VRB to PRB Mapping 37119.6.5.7 Reference Point “A” 37119.6.6 Channel and Transmission Bandwidths 37119.6.7 Bandwidth Part (BWP) 37319.6.7.1 Types of BWP 37419.6.7.2 BWP Configuration 37519.6.7.3 BWP Switching and Associated Delay 37619.6.8 NR Resource Allocations 37719.6.8.1 Frequency Domain Resource Allocation for FDD Transmission 37719.6.8.2 Time‐Domain Resources Allocation for FDD Transmission 38019.6.8.3 Time‐Domain Resources Allocation for TDD 38319.6.9 Transport Channels and Their Processing Chain 38419.6.9.1 CRC Calculation and its Attachment to a Transport Block 38519.6.9.2 Code Block Segmentation 38519.6.9.3 Channel Encoding with LDPC 38619.6.9.4 Rate Matching and Concatenation 38719.6.9.5 Multiplexing of UL‐SCH Data and Uplink Control Information 38819.6.9.6 LDPC Encoding Examples 38819.6.10 Physical Channels and Their Processing Chain 39019.6.10.1 Physical Channels 39019.6.10.2 Channel Mappings 39119.6.10.3 Multiple Physical Antenna Transmissions 39219.6.10.4 Physical Channel Processing Chain 39519.6.10.5 Physical Downlink Control Channel (PDCCH) 39719.6.10.6 Physical Uplink Control Channel (PUCCH) and Information (UCI) 40419.6.11 Code Block Group‐Based Transmission and Reception 40519.6.12 Physical Signals 40919.6.12.1 Reference Signals Transmitted as Part of Physical Channels 41019.6.12.2 Sounding Reference Signals 41219.6.13 Downlink Synchronization 41419.6.14 Millimeter Wave Transmission, Beamforming, and Its Management 41919.6.15 Cell‐Level Radio Link Monitoring (RLM) 42419.6.16 RRM Measurements for UE Mobility 42619.6.16.1 RRM Measurement Signals and Their Quantities 42619.6.16.2 RRM Measurements Framework 42719.6.16.3 Overall RRM Process 42919.6.17 Channel State Information (CSI) 43019.6.18 Modulation and Coding Schemes (MCSs) 43319.6.19 Link Adaptation Procedure 43419.6.20 Random Access (RACH) Procedure 43519.6.21 NR Radio Resources Management (RRM) Procedure 43919.6.22 UE Transmit Power Control 44419.6.22.1 Types of Power Control Procedure in NR 44419.6.22.2 UE Transmit Power Determination Procedure in NR 44519.6.23 Effect of Physical Layer on Data Throughputs 445Chapter Summary 44620 5G Core Network Architecture 44720.1 Control Plane and User Plane Separation – CUPS 44720.1.1 Impacts of CUPS Feature 44820.1.2 CUPS in the LTE/EPC Network 44920.1.3 CUPS Feature in 5G Core Network 45020.2 Service-Based Architecture (SBA) 45220.2.1 Network Functions and Its Instances 45320.2.2 Network Functions (NFs) and Their Services Interfaces 45420.2.3 5G System Architecture with NF 45620.2.4 Network Functions and Their Services and Operations 45720.2.5 Network Functions Services Framework 45820.2.6 Services API for Network Functions 46220.2.7 Network Function Selection 46820.3 Network Function Virtualization (NFV) 469Chapter Summary 47221 5G System: Low-level Design 47321.1 Design of 5GC Service Interface and Its Operations 47321.2 Design of 5GC NF Service Interface Using UML and C++ Class Diagram 47421.3 Usages of C++ Standard Template Library (STL) 47521.4 Software Architecture for 5G System 47621.4.1 NG-RAN Logical Nodes Software Architecture 47621.4.2 5GC Software Architecture 47921.5 Data Types Used in 5GC SBI Communications 479Chapter Summary 49122 3GPP Release 16 and Beyond 49322.1 5GS Enhancements as Part of Release 16 49322.2 5GS New Features as Part of Release 16 49422.3 3GPP Release 17 496Chapter Summary 496Appendix 497References 503Index 507

"The author provides a comprehensive summary on the mobile communications systems covering 2G, 3G, 4G and 5G. The great addition to the theoretical foundations are practical elements including system operation and development aspects, with multitude practical examples and self-assessment. This handbook shall be useful for telecom practitioners including radio and core network engineers. It’s also a good source for software engineers from a different domain who would like to enter the telco domain. It shall be of interest to those, especially in present times where IT, software development and mobile communications are closer to each other than ever before."- Marcin Dryjański, Ph.D., PRINCIPAL CONSULTANT / CEO