5G Core Networks

Powering Digitalization

Stefan Rommer,Peter Hedman,Magnus Olsson,Lars Frid,Shabnam Sultana,Catherine Mulligan

• Publisher: Academic Press
• Year: 2019
• ISBN:
  9780081030103
• Topic: Computer Science
• Subtopic: Computer Networking
• Index: Computer Science

5G Core Networks: Powering Digitalization provides an overview of the 5G Core network architecture, as well as giving descriptions of cloud technologies and the key concepts in the 3GPP rel-15/16 specifications. Written by the authors who are heavily involved in development of the 5G standards and who wrote the successful book on EPC and 4G Packet Networks, this book provides an authoritative reference on the technologies and standards of the 3GPP 5G Core network.

Content includes:

• An overview of the 5G Core Architecture
• The Stand-Alone and Non-Stand-Alone Architectures
• Detailed presentation of 5G Core key concepts
• An overview of 5G Radio and Cloud technologies

Learn

• The differences between the 5G Core network and previous core network generations
• How the interworking with previous network standards is defined
• Why certain functionality has been included and what is beyond the scope of 5G Core
• How the specifications relate to state-of-the-art web-scale concepts and virtualization technologies
• Details of the protocol and service descriptions
• Examples of network deployment options

• Provides a clear, concise and comprehensive view of 5GS/5GC
• Written by established experts in the 5GS/5GC standardization process, all of whom have extensive experience and understanding of its goals, history and vision
• Covers potential service and operator scenarios for each architecture
• Explains the Service Based Architecture, Network Slicing and support of Edge Computing, describing the benefits they will bring
• Explains what options and parts of the standards will initially be deployed in real networks, along with their migration paths

Chapter 1

Introduction

Abstract

This chapter provides an overview of how the 5G standards started and some of the key background areas that readers need to understand the specifications. The final section of the chapter outlines the structure of the book.

Keywords

5G; 5G core; 5G networks; Introduction; Chapter summaries

1.1 5G—A new era of connectivity

The telecommunications industry has embarked on a dramatic transition and one that—if successful—will see it redefine its role in industry and society. 5G, while often portrayed as a tool for higher speeds or critical to the development of the so called Industry 4.0, represents a foundational shift for wireless communications—one that places it directly at the center of a truly digital economy. This overhaul of communications is therefore unlike any that have gone before it—it is not the same as the move from 2G to 3G or 3G to 4G—it is a step change that the industry may not see again for quite some time.

The 5G architecture itself consists of two parts—the new Radio Network (NG-RAN) supporting the New Radio (NR), and the 5G Core Network (5GC). Both have changed considerably compared to previous generations of technology. This book focuses on 5GC, providing short forays into NR where it aids understanding of the interactions towards the core network. A detailed description of NR is, however, beyond the scope of this book and interested readers are directed to Dahlman et al. (2018).

1.2 A step change

The first broad scale adoption of mobile technologies started with GSM (2G)—released in 1991, which focused on calls and text messaging. WCDMA (3G), released in 1999 gave consumers the ability to browse the internet and use feature phones. It was not until the introduction of LTE (4G)—in 2008, however, that we saw the broad adoption of Mobile Broad Band (MBB) and the uptake of video and data traffic on the all-IP network including the development of ‘apps’ on smartphones. Each generation saw a large increase in bandwidth and speeds provided with end-user consumers as the core focus. 5G is unlike the previous generation of networks; it represents a shift from operators having end-users as customers to over time having industries as their main customers. This represents not just a technology shift, but a business model shift unlike any previously as well. New players may very well enter the market because of the disruptive capabilities of 5G.

5G is a more ambitious approach to network architectures—not only incorporating requirements from the telecommunications industry but other industries and at the same time including cloud-native and web scale technologies such as HTTP. It is quite simply a new approach to developing architecture and delivering services on a global scale.

1.3 A new context for operators

Broken up into building blocks covering access, transport, cloud, network applications and management (including orchestration and automation), 5G systems aim to provide a higher level of abstraction designed to simplify network management and operations. In addition, new services will need to be rapidly implemented on the network as new business models emerge that demand operators move to programmable, software-based networks that deliver services on-demand and in an ‘as a Service’ manner. Throughout this book, we illustrate where the technology itself overlaps with some of these new business models providing a unique insight into how some of those decisions have been made. In addition, where previously human customers were making requests of the networks, with 5G there is an increased level of non-human, i.e., machine and software, requests that means the entire way services are developed and delivered needs to change.

1.4 The road to 5G network deployments

The initial work on defining the requirements and vision on 5G networks was carried out in ITU-R in 2012. ITU formally refers to this as IMT-2020. A good reference is Dahlman et al. (2018). This was followed by multiple more detailed studies in ITU-R itself, as well as in industry fora and research projects around the world.

The initial work to develop the 5G specifications to meet the ITU-R IMT-2020 requirements was done in 2014, picking up speed in 2015 and 2016. Trials of 5G systems have been in place in several countries, with commercial rollouts planned for most markets around 2020. Outlining the core network evolution in an easy to use and accessible manner so that engineers and other interested parties can understand the changes brought about by 5G is therefore the core reason for us writing this book.

Several early commercial 5G systems became available already from late 2018 and early 2019. Some initial 5G network deployments include:

• • Verizon and AT&T have both launched USA's first 5G services during 2018 and 2019
• • Telstra has rolled out multiple 5G areas across Australia during 2018 and 2019
• • Services targeting enterprise use cases launched by all three Korean operators by the end of 2018
• • Early eMBB services were launched in Korea, the U.S., Switzerland and the U.K. in the first half of 2019

1.5 3GPP release 15 and 16

5G Core is described in a set of specifications developed by the 3rd Generation Partnership Project (3GPP) and captured in Release 15 (Rel-15) and subsequent releases. Rel-15 was the first full set of 5G standards and was released in several steps between June 2018 and early 2019. Rel-16 is planned to be released early 2020 and planning of work has commenced on Release-17 with an aim to have specifications ready in 2021 or 2022.

Rel-15 contained e.g.:

• • Architecture for Non-Stand Alone (NSA), i.e., New Radio (NR) used with the LTE and EPC infrastructure Core Network
• • Architecture for Stand-Alone (SA), i.e., NR is connected to the 5G Core Network (5GC)
• • 5GC using a Service-Based Architecture (SBA)
• • Support of virtualized deployment
• • Network functionalities to provide registration, deregistration, authorization, mobility and security
• • Data communication with IP, Ethernet and Unstructured data
• • Support of concurrent local and central ac...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Forewords
• Acknowledgments
• Chapter 1: Introduction
• Chapter 2: Drivers for 5G
• Chapter 3: Architecture overview
• Chapter 4: EPC for 5G
• Chapter 5: Key concepts
• Chapter 6: Session management
• Chapter 7: Mobility Management
• Chapter 8: Security
• Chapter 9: Quality-of-Service
• Chapter 10: Policy control and charging
• Chapter 11: Network slicing
• Chapter 12: Dual connectivity
• Chapter 13: Network functions and services
• Chapter 14: Protocols
• Chapter 15: Selected call flows
• Chapter 16: Architecture extensions and vertical industries
• Chapter 17: Future outlook
• References
• Abbreviations
• Index