Road to 5G: Introduction and Migration April 2018 ROAD TO 5G: INTRODUCTION AND MIGRATION About the GSMA Future Networks Programme The GSMA represents the interests of mobile operators The GSMA’s Future Networks is designed to help operators worldwide, uniting nearly 800 operators with almost 300 and the wider mobile industry to deliver All-IP networks so companies in the broader mobile ecosystem, including that everyone benefits regardless of where their starting handset and device makers, software companies, point might be on the journey. equipment providers and internet companies, as well as The programme has three key work-streams focused on: organisations in adjacent industry sectors. The GSMA also The development and deployment of IP services, The produces industry-leading events such as Mobile World evolution of the 4G networks in widespread use today, The Congress, Mobile World Congress Shanghai, Mobile World 5G Journey developing the next generation of mobile Congress Americas and the Mobile 360 Series of technologies and service. conferences. For more information, please visit the Future Networks For more information, please visit the GSMA corporate website at: www.gsma.com/futurenetworks website at www.gsma.com. Follow the GSMA on Twitter: @GSMA. Document Editor Dongwook Kim, 5G Project Manager Michele Zarri, Technical Director – Networks Acknowledgement (5G Introduction Project Members) Applied Communication Sciences MediaTek Inc. ARM Ltd. Nokia AT&T Mobility NTT DOCOMO, Inc. Axiata Group Berhad OranGe China Mobile Limited Qualcomm Incorporated China Telecommunications Corporation SinGTel Mobile SinGapore Pte. Ltd. China Unicom SK Telecom Co., Ltd. Deutsche Telekom AG SoftBank Corp. DISH Network Corporation Sprint Corporation Ericsson Syniverse TechnoloGies, Inc GuanGdonG OPPO Mobile Telecommunications Corp.,Ltd. Telecom Italia SpA Huawei Technologies Co Ltd Telefónica S.A. iBasis, Inc Telenor Group Intel Corporation Telia Finland Oyj KDDI Corporation T-Mobile USA, Inc KPN B.V. Turkcell Iletisim Hizmetleri A.S. KT Corporation United States Cellular Corporation Kuwait Telecom Company (K.S.C.) Videotron Ltd LG Electronics Inc Vodafone RoaminG Services S.à r.l LG Uplus, Corp. ZTE Corporation ROAD TO 5G: INTRODUCTION AND MIGRATION Contents Executive Summary 5 4.3.4 Impact on device and 22 1 Introduction 8 network 1.1 Scope 9 4.3.5 Impact on voice including 22 service continuity 1.2 Abbreviations 9 4.4 NSA Option #3 to NSA 23 1.3 References 11 Option #7 and SA Option #5 2 Why 5G? 12 4.4.1 Description 23 2.1 The advent of the 5G era 13 4.4.2 Feasibility of the path in 23 2.2 Drivers of 5G 13 meeting 5G use cases 2.3 Expectations on 5G 13 4.4.3 Deployment considerations 23 2.4 Use cases and spectrum 14 4.4.4 Impact on device and 23 bands for 5G network 4.4.5 Impact on voice including 24 Part I 15 service continuity 3 5G Network Deployment 15 4.5 NSA Option #3 to NSA 24 Options Option #3 and SA Option #2 3.1 Standalone (SA) and Non- 16 standalone (NSA) 4.5.1 Description 24 3.2 Evolved Packet Core (EPC) 16 4.5.2 Feasibility of the path in 24 and 5G Core Network (5GC) meeting 5G use cases 4.5.3 Deployment considerations 24 4 5G Network Introduction & 18 4.5.4 Impact on device and 24 Migration Paths network 4.1 General observations and 19 4.5.5 Impact on voice including 25 assumptions service continuity 4.2 EPS to SA Option #2 19 4.6 NSA Option #3 to NSA 26 Option #4 and SA Option 4.2.1 Description 19 #2 4.2.2 Feasibility of the path in 19 4.6.1 Description 26 meeting 5G use cases 4.6.2 Feasibility of the path in 28 4.2.3 Deployment considerations 19 meeting 5G use cases 4.2.4 Impact on device and 20 4.6.3 Deployment considerations 26 network 4.6.4 Impact on device and 27 4.2.5 Impact on voice including 20 network service continuity 4.6.5 Impact on voice including 27 4.3 EPS to NSA Option #3 21 service continuity 4.3.1 Description 21 4.7 Other migration steps 27 4.3.2 Feasibility of the path in 21 meeting 5G use cases 5 Recommendations for 28 4.3.3 Deployment considerations 21 collaborative actions ROAD TO 5G: INTRODUCTION AND MIGRATION 7.1.2 5GC (5G Core) 42 Part II 30 7.2 Comparison of EPC and 44 6 Study of 5G Network 30 5GC Introduction Case 6.1 Why 5G? 31 8 Detailed considerations on 45 6.1.1 5G technology and service 31 5G deployment options trial activities 8.1 Standalone considerations 46 6.1.2 Other business/social 32 8.2 Non-standalone 46 drivers in the nation considerations 6.1.3 Deployment purpose and 33 spectrum at disposal 9 Impact on voice including 49 6.2 Analysis of 5G migration 34 service continuity options 9.1 Options for operator 50 6.3 Rationale behind migration 35 voice/video option communications service in 6.4 Challenges in actual 36 5G migration 9.2 Recommendations for 51 6.5 Lessons learned from 38 voice/video migration case study communications service in 5G Part III 40 Annex A 52 7 Core network 40 considerations Other considerations for operators 7.1 Core network solutions 41 A.1 Status Icon related to 5G 53 7.1.1 EPC (Evolved Packet Core) 41 ROAD TO 5G: INTRODUCTION AND MIGRATION Executive Summary Unlike previous generations of mobile networks, cases effectively while supporting global the fifth generation (5G) technology is expected interoperability. to fundamentally transform the role that telecommunications technology plays in the This document therefore analyses the alternatives society. 5G is also expected to enable further available for operators intending to introduce a economic growth and pervasive digitalisation of a 3GPP compliant 5G system migrating from their hyper-connected society, where not only are all 3GPP 4G network. The structure of the document people connected to the network whenever is as follows: Part I provides an high level needed, but also many other devices/things description of the 5G introduction and subsequent virtually creating the society with everything migration along recommendations for connected (i.e. Internet of Everything). 5G will collaborative actions while Part II delves into real therefore enable new use cases such as smart operator case study and Part III provides cities, smart agriculture, logistics and public safety advanced technology considerations requiring a agencies. Furthermore, there are a variety of reasonably advanced level of understanding of the spectrum bands available for deployment of 5G, 3GPP system. which can be sub-divided in three macro While 3GPP is defining both a new 5G core categories: sub-1GHz, 1-6GHz and above 6GHz. network (5GC) as well as a new radio access In addition, 3GPP (3rd Generation Partnership technology called 5G “New Radio” (NR), it is Project) has specified new 5G radio access possible to integrate elements of different technology, 5G enhancements of 4G (fourth generations in different configuration with 5G: SA generation) network, and new 5G core network. (standalone) and NSA (non-standalone). SA The variety of requirements and spectrum needs scenario uses only one radio access technology show that there are many options of 5G (5G NR or the evolved LTE (Long Term Evolution) introduction and different spectrum bands will be radio cells) and the core networks are operated needed to support all use cases. Operators must alone. NSA scenario combines NR radio cells and therefore consider the feasibility of different LTE radio cells using dual-connectivity to provide options in meeting their intended initial use cases radio access and the core network may be either and interoperability of their choice with other EPC (Evolved Packet Core) or 5GC (see Table 1 options to ensure their networks deliver the use for details). Table 1: Comparison of 5G radio access and core networks Advantages Disadvantages • Simple to manaGe • Not able to leveraGe existinG SA • Inter-generation handover LTE deployments if NR is used Radio between 4G-5G in SA access • TiGht interworking between LTE network • LeveraGe existinG LTE NSA and NR required deployments • May impact end user experience • LeveraGe existinG EPC EPC • Cloud support is optional deployment Core network • Cloud native 5GC • Easier to support multiple • New deployment required access 5 ROAD TO 5G: INTRODUCTION AND MIGRATION Figure 1: 4G and 5G Deployment Options Consequently, five deployment options are • NSA Option #3 to NSA Option #3 and SA available for 5G as depicted in Figure 11. Red Option #2 colour denotes NR and 5GC. • NSA Option #3 to NSA Option #4 and SA Option #2 NOTE: for simplicity, the figure does not depict control and user plane connection The analysis of the paths (see Table 2) take four perspectives. First, feasibility of use case refers to As there can be multiple paths to reach the final the ability of the path in addressing 5G use cases. target configuration that an operator intends to Second, deployment considerations consider the deploy, it is essential to consider migration steps support for early 5G devices and core network & that would comprise different paths. This radio access network deployment considerations document analyses the following migration steps of the migration step (i.e. the core network that the 5G Introduction project group members solution adopted as a result of the path and the believe to be more likely. extent of leveraging existing LTE deployment). Third, impact on device and network considers • EPS (Evolved Packet System) to SA Option the impact of the migration step on device and #2 • EPS to NSA Option #3 network.