Design, deployment and SW validation to virtualize a mobile data core network to use 5G technology in Vodafone

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(1)Trabajo Fin de Máster. ESCUELA TÉCNICA SUPERIOR DE INGENIERÍA Y SISTEMAS DE TELECOMUNICACIÓN.

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(3) DESIGN, DEPLOYMENT AND SW VALIDATION TO VIRTUALIZE A MOBILE DATA CORE NETWORK TO USE 5G TECHNOLOGY IN VODAFONE. M ASTER T HESIS BY. A NDREA VALLEJO P UIGVERT J ULY 8, 2018. S UPERVISORS C ÉSAR B ENAVENTE F INI I RLES M ARTA DE PABLOS. U NIVERSIDAD P OLITECNICA DE M ADRID I NTERNET T ECHNOLOGY AND A RCHITECTURE EIT D IGITAL M ASTER S CHOOL.

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(5) A CKNOWLEDGEMENTS I would particularly like to single out my supervisor and mentor Marta de Pablos, who always was willing to help me not only with her patient, dedication, enthusiasm, and immense knowledge but also with her motivating speeches which have helped me overcome any difficulty. I could not have imagined having a better advisor and mentor for this master thesis. I would like to sincerely thank my internship supervisor Fini Irles of the Data Core department at Vodafone, for making this thesis possible and for her valuable support and guidance during my internship with her. I also like to thank all the Vodafone, Altran and Huawei experts who were involved in this project and who helped me with their advice and explanations: Mario Pérez, Sergio Carretero, María Jesús Jiménez, Raquel Perdiguero, Luisfer Bartolomé, César Antón, Fran Pariente, Juan Manuel Temprado, Jorge Salas, Patricia Sánchez, Jesús Rodríguez, and Ángel Báez. Without their passionate participation and input, this project would not have been successfully made. I would also like to acknowledge César Benavente of the Department of Signal Theory and Communications at the Polytechnic University of Madrid for having his office door always open whenever I had a question about how to focus my research. Furthermore, I am gratefully indebted to him for his very valuable comments on this thesis. And last but not least, I must express my very profound gratitude to my parents and to my sister for providing me with unfailing support and continuous encouragement throughout my years of study and through the process of researching and writing this thesis. This accomplishment would not have been possible without them.. Thank you.. I.

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(7) C ONTENTS Acknowledgements. I. Contents. II. Abstract. V. 1 Introduction 1.1 Thesis Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1 4. 2 Businesss Plan 2.1 Executive Summary . . . . . . . 2.2 Company Description . . . . . 2.3 Business Drivers . . . . . . . . . 2.4 Value Proposition . . . . . . . . 2.5 Market Analysis . . . . . . . . . 2.5.1 Competitors . . . . . . . 2.5.2 Customer Segmentation 2.6 Validation . . . . . . . . . . . . 2.7 Go to the Market Strategy . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. 5 5 6 7 9 10 10 14 15 15. 3 Project Planning 17 3.1 Time plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.2 Precedence diagram method (PDM) . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.3 Budget . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 4 Technical Background 4.1 Techniques for virtualization . . . . . . . . . . . . . . 4.1.1 Network Function Virtualization (NFV) . . . . 4.1.2 Software Defined Networking (SDN) . . . . . . 4.2 Virtualized Network Architecture and Services . . . . 4.2.1 Virtual Evolved Packet Core (vEPC) Elements 4.2.2 vEPC Services . . . . . . . . . . . . . . . . . . . 4.3 5G Networks . . . . . . . . . . . . . . . . . . . . . . . . 4.3.1 Mobile Edge Computing (MEC) . . . . . . . . 4.3.2 Control Plane - User Plane Separation (CUPS) III. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. . . . . . . . . .. 29 30 30 32 34 34 38 39 40 42.

(8) CONTENTS 4.3.3 Non Stand-Alone and Stand-Alone Networks . . . . . . . . . . . . . . . . 44 4.3.4 Network Slicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 5 Deployment 5.1 Network Funtion Virtualization Infrastructure . . . . . . . . . . . . . . . . . . . . 5.1.1 Network Function Virtualization Infrastructure (NFVI) Physical Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1.2 NFVI Virtual Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 NFVI Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 Connectivity Desing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3.1 Low Level Design (LLD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.4 Installation and Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 Software (SW) Validation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.1 Cases Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.2 Environment Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.3 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 47 47 48 50 51 54 59 63 65 65 67 71. 6 Conclusion and Future Work 105 6.1 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 6.2 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 A Abbreviations. 107. B Additional Information. 115. C Cases List. 119. List of Figures. 139. List of Tables. 140. List of Traces. 141. Bibliography. 147. Declaration. 149. IV.

(9) A BSTRACT The world of telecommunications is constantly changing. Customers expectations are constantly growing, pushing the market to adapt in order to meet new customers needs. In this environment, new business models are created mainly focused on boosting data transfer, turning into an aggressive growth of data in mobile networks. In fact, only during last year, data consumption increased by 70%. On the other hand, customers want to enjoy this data at any moment, in any place, and through a real-time experience. Due to this digital revolution, mobile communication is now one of the key essential services that society needs and demands. Within this framework, all mobile phone operators and in particular Vodafone Spain are facing a great challenge. Vodafone needs to cope with this new scenario, increasing its network capacity and its speed in data transfer. However, expanding the legacy network without increasing tariffs is no longer profitable. It is time to introduce new technologies suitable for this huge and constant data growth. Replacing the old bare metal network with a new virtualized one is something that becomes necessary for Vodafone in order to continue being a leading company in its sector. The advantages of virtualization will bring economic benefits for the company and will help Vodafone to be prepared for this new paradigm change. On top of this, Vodafone wants to be the leader in innovation and it is constantly developing new technologies that will help to create new products and services for this new digital society. The new virtualized network is the perfect scenario to take the first steps beyond the implementation of the new 5G mobile generation in Spain. The digital transformation is already changing the industry and society and Vodafone is already working to change our daily life.. The future is exciting, are you. V.

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(11) 1 I NTRODUCTION Since the market and the needs of people are constantly changing, mobile phone operators have many new challenges to face, as well as new opportunities to take advantage of. One of the main changes that the market is experiencing, is the growing penetration of smartphones. This growth is resulting in a higher demand for mobile data. Users are demanding better and faster quality services at any time and in any place. In this context, new Over the Top (OTT)s are trying to break into the market to offer new applications and services to customers. This situation has created more competitiveness among them and has brought new innovative ideas and business models. Nowadays, OTTs like Netflix or Amazon can generate revenues from their services faster than in the past. And this is thanks to the fact that they are growing and changing continuously, following the consumer demand. In addition, OTTs are also responsible for causing an exponential increase in data consumption, and more specifically the ones that offer high-definition video. Therefore, for the optimal functioning of all these applications and services, new and better data core network resources are required. What does this mean for mobile operators? if they want to support these services and applications, they should move fast to adapt all their infrastructures, according to the new requirements imposed by consumers and OTTs. This is why Vodafone decided to renovate its data core network by virtualizing it. However, these are not the only reasons that are pushing mobile operators to change. There are also other factors such as the new competitors that are emerging in the market through the Mobile Virtual Network Operator (MVNO). This new concept of operators is shaking the market by decreasing the prices of their services. This fact is impacting all the consolidated operators in the Spanish market. In fact, the most impacted one in the past few months is Vodafone, losing a large customer base due to the high customer churn rate. Virtualization is not only the enabler for this quick adaptation but also a new source of revenues because the user is allowed to consume more. So, the higher the consumption, the greater the benefit. Furthermore, virtualization allows the implementation of new network architectures, such as MEC or network slicing, that are the main enablers for new subscription services key to monetizing customers relationships. Vodafone wants to stop being just the data access pipe for customers to become also a 1.

(12) CHAPTER 1. INTRODUCTION company that offers added value services to its users through the new technologies. In order to virtualize the network, some tools are needed. NFV is a method which allows virtual instances of physical networks to be separated in virtual resources. These resources can work in independent sections or combining them with the objective of providing network services. The aim of network virtualization is to improve the productivity and efficiency of legacy networks by performing tasks automatically. Moreover, this kind of networks can be managed in a central way through a single physical site. SDN is a set of techniques whose goal is to facilitate the implementation of network services in a deterministic, scalable and dynamic way. Thanks to SDN, it is possible to avoid the network administrator to manage such services at a low level, improving network performance and monitoring. NFV and SDN are the best allies to quickly adapt the network to the different changes since they can virtualize the network functions of the traditional network. This is made by dynamically adapting, arranging and distributing the available resources according to the demand. Hence, any modification is fast and easy, reducing costs and improving the time-to-market. In addition, using virtualization over the network brings the opportunity to obtain new revenues: - On one hand, SDN allows the network to direct the data traffic flows, without the need to rely on the Hardware (HW). Therefore, all decisions are taken by SW and there is no need to provision or configure the network in a manual way. This brings benefits to the network, such as: Increase automation, enhance security, reduce operating costs, cloud-ready infrastructure. - On the other hand, NFV can modify the services and features of the applications on demand to better suit the needs of the consumers. In addition, it also works without needing to make any changes in the HW since all the modifications are made on the SW. Another advantage of NFV is that it is possible to rapidly scale services and applications up or down and place it wherever is needed over the network. For instance, centralizing, distributing, or placing it closer to the consumer by using MEC, or creating layers with specific functionalities according to each service or application by using Slicing. As a conclusion, thanks to NFV and SDN, there is no need to have one HW per function, as it was before since the functions are virtualized. As a result, there is a reduction in the Capital Expenditures (CAPEX) and Operating Expenses (OPEX) of the company. Moreover, thanks to these two tools, the network can not only be virtualized but also facilitates the support of future 5G technologies. Furthermore, virtualization is the first step that brings closer the reality of 5G in the data core networks by using Non Stand-Alone (NSA) architectures. Once this step will be done, the following phases will consist of adapting the data core to the new architecture, called Stand-Alone (SA), standardized by the Third Generation Partnership Project (3GPP) organization. 5G will brings more innovation and new business ideas based on low latency applications. Furthermore, the areas of use are very broad, for instance: health and wellbeing, automotive and mobility, security and surveillance, industry and manufacturing, energy, smart city, education, learning, or entertainment, among others. 2.

(13) CHAPTER 1. INTRODUCTION However, not all are advantages in the virtualized environment since there is a long journey to get there and a lot of challenges to face. First of all, there are new Network Element (NE)s that need to be developed, following the already established 3GPP standard. Another challenge is the adaptation to services on-demand, which will need to be a dynamic and policy-based. Besides, for managing all this, it is necessary to integrate an infrastructure with a real-time analytics. In order to implement all this, it is necessary to carry out several tasks, such as: Integration and dimensioning, connectivity desing, NEs instalations, NEs configuration, SW , and production deployment. All these steps need to be done fast, always taking into account the time-to-market. The objective of this thesis is to show the reader all the necessary steps to virtualize the data core network of Vodafone. To do this, all activities that were carried out will be explained, covering business and technical areas. Therefore, this master thesis is mainly divided into two parts: - The first part has a more business approach. Here, there will be explained the problems that Vodafone had to face, and for which Vodafone had to make the decision to modernize its network. It will also expose in detail its value proposition, detailing the services that Vodafone will offer to their clients. Besides, the results of the market studies will be indicated, showing which are the direct competitors of Vodafone, as well as its customer segmentation. Additionally, the Vodafone’s go-to-market strategy will be exposed, on which the company wants to attract more customers. Finally, the management part of the project will be detailed. The intention of this section is to give the reader a general view of how a project of this type can be structured in scope, time and cost. - The second part of the thesis, is more focused on the technical approach. It will start with the legacy network overview and it will cover all the steps needed to virtualize the network, deep diving on the NEs design and implementation. Specifically, this thesis will be mainly focused on the following platforms: Virtual Unified Packet Gateway (vUGW) and Virtual Unified Serving Node (vUSN), which could be considered the two most important nodes to ensure the proper functioning of the network. Both platforms are provided by Huawei company since Vodafone has opted to renew its network with products of this company. Additionally, the NEs Centralized Gateway (CGW) and Distributed Gateway (DGW)which conforms the vUGW in 5G networks (NSA), will be introduced to the reader. Therefore, all the technical activities involved in carrying out this project will be explained in detail. For instance, Integration and dimensioning, connectivity desing, NEs instalations, NEs configuration, and SW validation. Finally, the results of the tests carried out in the platforms vUSN, vUGW, CGW, and DGW will be exposed and commented.. 3.

(14) CHAPTER 1. INTRODUCTION. 1.1. T HESIS O UTLINE. This thesis is structured in six chapters, as follows: • Chapter 1: First chapter is the introduction, where is a summary of the subject of this thesis, as well as the motivations. • Chapter 2: Second chapter presents the business plan of this project on virtualization of the network and 5G. The company description, value proposition, goals, market analysis, strategy, are shown in this chapter. • Chapter 3: Third chapter introduces the project planning, with all the schedules and activities performed during the project, as well as the and budget used. • Chapter 4: This chapter gives an overview of the technical background. Here, topics like techniques for virtualization, virtualized network architecture, and 5G networks are explained. • Chapter 5: Chapter five has the technical deployment description. Furthermore, this chapter will give details about the virtual infrastructures used during the deployment of the virtual network. Besides, the connectivity design will be discussed. Moreover, the procedure used to install and configure all the platforms is shown, as well as the use cases, SW Validation and its results. • Chapter 6: The final chapter gathers the conclusions that have been reached after carrying out this thesis, as well as possible future works.. 4.

(15) 2 B USINESSS P LAN This chapter gathers all the parts that make up the business plan for this project. It is divided into seven parts: First, a brief summary of the business plan will be presented to have an overview of the chapter. Second, a company description will be provided to know what was the beginning of Vodafone, and how it has managed to be one of the best mobile operators in the world. Furthermore, in the third section, the Business Drivers section is presented. The idea is to provide the reader with all the reasons why Vodafone has decided to modernize its data core network, and what they want to achieve with it. The value proposition is the fourth part of this chapter. Here, it is explained why the customer should buy the products and services that Vodafone provides with its new data core network. In the fifth section, there are two studies which analyze the market status: One to deep dive into the main competitors and another to be aware of the customer segmentation. Following, it is exposed the main steps necessary to validate the services and products offered by Vodafone. This section will be more developed in Chapter 5, where all the details of how this implementation was made are presented. Finally, the seventh section gathers information about which is the Vodafone’s pricing strategy, as well as its promotion strategy to sell their products and services.. 2.1. E XECUTIVE S UMMARY. During the last years, the situation of the mobile telephony market has changed radically. On one hand, Vodafone has lost around 243,900 users because of very aggressive marketing campaigns carried out by Orange, and also due to the low prices strategy of MásMóvil. This places Vodafone as the third mobile phone company in Spain behind Movistar and Orange. On the other hand, there is more and more data consumption and more applications that demand high performance from operators’ data core networks. For those reasons, Vodafone has decided to bet on virtualizing its data network in order to be able to increase resilient capabilities and network performance, improving user experience and increasing profitability, that in the end comes into loyalty. 5.

(16) CHAPTER 2. BUSINESSS PLAN The main competitors of Vodafone are Movistar, Orange and MásMóvil but currently main one is MásMóvil due to its powerful price campaign that is increasingly, attracting users of other operators. The new services that can be implemented thanks to the Vodafone data core network virtualization, are mainly focused on people from Europe, who are individual clients between 18 to 30 year old, and who are located in urban and semi-urban areas. Moreover, the pricing strategy will be based on the quality of service offered. The higher the quality of the service, the higher the pricing. However, these prices will be adapt depending also on the competitors pricing strategy. All these will be promoted by an aggressive campaign, where all the products and services will be advertised through as many channels as possible, like TV, radio, press, and social media, among others.. 2.2. C OMPANY D ESCRIPTION. Vodafone is a telecommunications operator with headquarters in Newbury, United Kingdom. It was initially known as Racal Telecom in 1983, but in 1991 it was finally founded as Vodafone. Vodafone has subsidiaries spread all over the world, and all these countries are part of the association called Vodafone Group. It provides mobile services in 26 countries, fixed broadband services in 17 countries and it has agreements with another 49 [34]. The economic benefits and the number of customers of Vodafone have consolidated the company as one of the most important telecommunication operators in the word. In fact, at the end of June 2017, Vodafone had more than 518 million mobile telephony customers, as well as more than 15 million fixed broadband customers. These numbers place Vodafone as the second bigger telecommunications operator in the world. One of the fourth big markets of Vodafone Group is Spain. Vodafone started there by buying Airtel’s shares in 1999, until taking control of the entire company. In addition, with the intention of continuing to grow, in 2014 Vodafone Spain bought the Corporative Group ONO, S.A., and went to the market with its first MVNO called Lowi. Nowadays, Vodafone Spain has about the 25% of the market share, with large numbers of consumers in the different services offered: 14.4 million mobile telephony customers, 7,5 million in 4G services, 3,2 million fixed broadband, 2,3 fibre, 1,3 Vodafone TV, and 2,3 Vodafone ONE. Figure 2.1 shows what has been the growth of the company in terms of customers, from 2014 to 2017. All these numbers, place Vodafone Spain in the third position, behind Movistar and Orange [37], [27]. The successes achieved by Vodafone Group and Vodafone Spain are the keys to consolidate this company as one of the most important in Spain. These achievements can be divided into several major milestones, where Figure 2.2 holds the most significant ones. All this could not have been achieved without having the best network infrastructure. Actually, Vodafone Spain is able to provide Global System for Mobile comunications (GSM) (2G) services at 900 and 1800 MHz, Universal Mobile Telecommunications System (UMTS) (3G) at 900 and 2100 MHz and Long Term Evolution (LTE) (4G) at 800, 1800, 2100 and 2600 MHz. Besides, the data core network of 4G is compatible with 4G+ which provides 6.

(17) CHAPTER 2. BUSINESSS PLAN. Figure 2.1: Customer Key Indicators (2016-2017) [34].. Figure 2.2: Milestones and Launches: Vodafone in Spain (1994-2016) [34].. a download high speed. Moreover, Vodafone’s network can cover around the 94% of the Spanish population with its coverage, being the best mobile operator in terms of coverage. In addition, it was selected as the winner of the P3 testing carry out in Spain [3]. For more information, see Subsection 2.5.1.. 2.3. B USINESS D RIVERS. The objective of this project is to change the Vodafone’s data core network to adapt and cover the new needs of the market and the users. Furthermore, the other main objective is to obtain new revenues stream thanks to the use of new technologies such as virtualization and 5G. Nowadays, people spend around 30 minutes per day watching videos on mobile devices, when in 2013 it was just 10 minutes every day. Besides, people also spend a lot of time with the phone to send messages to their friends. In fact, there are two main messaging applications: WhatsApp, Facebook Messenger, which have almost one billion monthly active users. In addition, around 60% of all payment transactions are now made digital. Moreover, it is estimated that there are more than 30 million Amazon devices in the homes of users, compared to 10 million at the end of 2016. All these show that there is an exponential increase in the consumption of data in the last two years, and more especially since the appearance of applications such as Instargram, or 7.

(18) CHAPTER 2. BUSINESSS PLAN platforms such as Netflix. To have a broader vision of the consumption that can be generated daily, Figure 2.3 has represented the most important OTTs currently and their Gbps per day consumed. The image shows that the applications that have a higher data consumption per day are YouTube and Instagram with their "Instagram Stories". Youtube has been consolidated as favourite channel of users to watch videos. But Instagram follows it closely, and it is expected to increase its numbers. The third application of video consumption is Netflix, although it still has enough to reach the other two previously mentioned. Video and audio download applications, such as BitTorrent, are losing strength. This is because more and more multimedia content is consumed through applications, and not by downloading files directly.. Figure 2.3: Top Apps – Daily Data Volume (GB/Day) [25].. Although the data consumption today is quite high, it is expected to increase even more. In fact, this traffic forecast is another factor for which Vodafone has decided to renew its network. In order to face this new situation, capacity, and data upload and download speeds will need to improve. Below, in Figure 2.4 is the traffic forecast of data that Vodafone expects to have in the coming months. In black, the demand that would be presented without considering the increase in data consumption is represented, while red line represents the new demand. It should be noted that there is a considerable peak in the month of August, and more specifically from 15t h of August, where the traffic forecast peak is 347 Gbps. This is due to the fact that as of that date there is a greater consumption of data for the summer holidays. In this month an increase of 25% is expected, and 7% in the following months. The solution found by Vodafone to deal with these new situation, is virtualization. Thanks to the use of virtualization, it is expected to cover this increase in data consumption and provide enough capacity to face unforeseen large spikes of data. Figure 2.5 has a representation of network capacity evolution. The traffic forecast expected is the line in red, and the resilient capacity in the future month, the line in blue. As it is possible to see, the resilient capacity is more than enough to cover these needs. The virtualization of Vodafone network will be done gradually. Lines carrying more data traffic will be virtualized first. After, it will be virtualized the rest of the lines. Figure 2.6 has 8.

(19) CHAPTER 2. BUSINESSS PLAN. Figure 2.4: Traffic forecast - Vodafone Spain [25].. represented how the scenario will be for March 2019, where a 45% of the network will be virtualized using Virtual Network Functions (VNF). In order to see more information about what is virtualization, go to Section 4, where there are explained the main concepts of this solution as well as some tools which are needed in order to implement it.. Figure 2.5: Traffic forecast vs. Capability [25].. 2.4. Figure 2.6: Forecast: VNF and Legacy in 2019 [25].. VALUE P ROPOSITION. The main objective of Vodafone is to connect people worldwide, allowing the users to enjoy communications across different mediums convenient & secure. Therefore, the client experience is one of the keys within the value proposition. To achieve this, Vodafone offers an improvement in its data core network, with which it manages to improve the resilient capacity of the network, as well as its performance. Therefore, it will be able to provide higher speed data transmission, and greater bandwidth, which will make the data user much faster than they have ever been. With this, Vodafone aims to surpass all its competitors and offer the user the opportunity 9.

(20) CHAPTER 2. BUSINESSS PLAN to use the best services from one of the best networks in the world. Vodafone also aims to reach more and more consumers, and therefore expand its market.. 2.5 2.5.1. M ARKET A NALYSIS C OMPETITORS. There are two types of competitors among mobile operators: Operators which have their own network called Mobile Network Operator (MNO), and operators called MVNO. The MVNO does not have its own infrastructure, so it uses the network of others in order to provide coverage to their customers. In the Spanish market, the operators with their own network are Vodafone, Movistar, Orange and Yoigo (recently adquired by MásMóvil). They have their own infrastructure and because of this reason, they are able to provide more and better services than the MVNO. However, the MVNO are in general cheaper than the MNO and they have been very well received by users. This is why it has increased the number of this kind of operators in the last years. These companies have been so successful that some MNO have created their own low-cost brands in order to compete with the MVNO. For instance, Vodafone has had created Lowi, which offers rates at lower prices. However, other mobile operators instead to create other brands, they have bought companies that already existed. Figure 2.7 has a map of how is the current situation of the relationships that exist between mobile operators in Spain.. Figure 2.7: Map of the main unions between mobile telephony operators in Spain.. The study of the competitors will be carried out, taking into account the four main operators with its own infrastructure, and the main competitor of the virtual operators. These are: Vodafone, Movistar, Orange and MásMóvil. In this first part, there is a more business approach where the situation in the market of all the operators will be evaluated. However, the second part will have a more technical 10.

(21) CHAPTER 2. BUSINESSS PLAN approach, where the technical features of each company will be compared. The following Figure 2.8, shows the market share of the main mobile telephony operators in Spain in December 2017. These statistics are related to the number of lines registered by each operator. The three main operators are Movistar, Orange and Vodafone, respectively, which have 80% of the total market. The rest of the market is for the set formed by the MVNO.. Figure 2.8: Market share of mobile telephone companies in Spain (December 2017) [29].. As seen in the image, Movistar is in the lead, followed closely by Orange in the second position, and Vodafone in the third position with a 24.9% share. Last year, Vodafone occupied the second position in this ranking, so it can be said that the results have worsened for them. It should also be noted the percentage of shares that MásMóvil has achieved in less than a year. These results are mainly due to two factors. The first is the appearance of the operator MásMóvil, which has made offers at a very low price, causing users migrations from other companies to MásMóvil. Secondly, there are the marketing campaigns carried out during 2017 by Orange. These campaigns were specially prepared to capture Vodafone users. Therefore, Vodafone has experienced large amounts of portability in this last year for these two causes. Figure 2.9 gives more details about this situation. On the left side of the image, the variation of registrations and portabilities that have been produced since January 2017 is represented. In this graph, it is clear that the company that has achieved the highest number of registrations is MásMóvil, with numbers that are much higher than the rest. As soon as Másmóvil appeared, Vodafone experienced an increase in portability. And after some months, Movistar and Orange have been affected as well. The main difference is that both Movistar and Orange, have almost maintained their number of customers, thanks to the fact that they also had an increase in registrations, which offset their high number of portabilities. But this is not the case with Vodafone, which, although also had high, these have not been enough to end the year in positive. On the right side of the image, the total number of users who have won or lost these four mobile telephony operators are represented. MásMóvil managed to end the year with 403,750 11.

(22) CHAPTER 2. BUSINESSS PLAN more users than at the beginning of the year 2017. This amount is very high and shows that this company has earned a place in the Spanish market for mobile telephony. However, observing the other three companies, it is clear that all have lost users. So, it is possible to affirm that these users made their portabilities to the operator of MásMóvil. Among these three companies, Vodafone has the worst results, with a loss of 243.900 users in one year. These results are the worst numbers they have ever had. Although Movistar also has losses of 129,235 and Orange of 145,650, the user losses of Vodafone are still significantly bigger.. Figure 2.9: Registrations and portabilities of 2017 in Spain [4].. Although Vodafone finished in the third position in a number of lines in 2017, it has been the company with the best results in the tests carried out by companies specializes in wireless coverage mapping. This thesis will discuss the results in particular of one of these companies: P3 Connect Mobile Benchmark. It measures network quality and identifies potential areas for improvement. The reason why this company is commented here and not other it is because its results are highly objective and it is considered authoritative. The tests were carried out in cars that travelled through 17 large cities of Spain (with more than 100,000 inhabitants each), as well as in small towns. In total, P3 Connect Mobile Benchmark ended up covering 11,520 kilometres in October 2017. The measurements were made using mobile phones that perform measurements of the voice and data services configured with 4G. For voice tests, test calls were made between vehicles and the quality of the audio was evaluated using broadband algorithms. And for the measurement of data tests, the maximum data volume was evaluated in uplink and downlink. Measurements were also made in video streaming, adapting the resolution of the video depending on the available bandwidth. The results show that all Spanish mobile operators have improved their networks compared to the previous year. But only Vodafone has managed to stand out above its competitors, remaining in the first position for the third consecutive year. Figures 2.10 and 2.11 have the results of these tests. Vodafone has the highest scores, both in voice and data, although it was not in the first position in crowd score. Movistar has the second best results, followed closely by Orange. 12.

(23) CHAPTER 2. BUSINESSS PLAN However, Yoigo was in the fourth position with the worst results, and very far from the third [3], [2].. Figure 2.10: P3 Measurements Results [3].. Figure 2.11: P3 Overal Results [3].. Looking more closely at the results in Figure B.1, it is possible to see the most representative values of voice measurements. They show the percentage of success in the calls, the time of configuration of the call (in seconds), as well as the average quality of the voice call. Vodafone continues to occupy the first place followed by Orange with regards the voice quality during calls. In addition, with respect to the success rate, Movistar ranks second, approaching Vodafone, which is again the first with an average success rate of 98.5% in all 13.

(24) CHAPTER 2. BUSINESSS PLAN measured areas. However, in the time necessary to establish a call, Orange occupies the first position being the fastest operator with an average of 3.3 seconds per call. In the case of Yoigo, the results obtained place them in the fourth position in all fields. Moreover, the results of the measurements made for evaluate the data transmissions, are in Figures B.2, B.3 and B.4. These images have the drive-tests in Cities Towns and road, respectively. The measures were carried out in the 4G networks of the operators (although it should be noted that, in the case of Yoigo, they still do not have the full deployment of LTE network). The results show that Vodafone is the clear winner over its competitors in all the comparative analysis that were made. Movistar obtained the second position and Orange the third. Yoigo, although it was in the last position, showed a remarkable improvement with respect to the previous results of P3 connect Mobile Benchmark [2].. 2.5.2. C USTOMER S EGMENTATION. Vodafone is well diversified geographically. Actually, it has subsidiaries spread all over the world: Albania, Australia, Czech Republic, Egypt, Faroe Islands, Germany, Ghana, Greece, Hungary, Iceland, India, Ireland, Italy, Malta, Netherlands, New Zealand, Portugal, Romania, Spain, Turkey, Qatar, UK, and Ukraine. However, the highest amount of Earnings Before Interests, Taxes, Depreciations and Amortizations (EBITDA), was achieved in Europe. Figure 2.12 has represented this distribution. This is closely related to the number of mobile users in each country. That is because, in Europe, there are many more mobiles per person than in other continents as in Africa, Asia or the Pacific. This is why the difference between continents is so big.. Figure 2.12: Geographical market segmentation [23].. Vodafone’s customers consist of retail customers, third-party resellers and corporate companies. Actually, 92% of its customers are individuals and families while an 8% are enterprises. Within the individual clients, their main target is people from 13 to 65 years old, and most of them are located in urban, semi-urban and rural areas. Although more specifically, the Vodafone’s target would be, youth and people located in urban and semi-urban areas, where there are more people who are willing to pay more for a premium service. Actually, the largest data consumption is among people aged 18 to 30 located in urban areas, [33], [8]. 14.

(25) CHAPTER 2. BUSINESSS PLAN. 2.6. VALIDATION. Once the decision to virtualize the network was made, many studies and manuals were made in order to know the theory of how to implement this solution. However, it is not a good idea to start virtualizing the whole data core network based only on these manuals since many failures can occur during the implementation and many users may be affected. For this reason, during the validation phase, a testbed line was created, which was smaller compared to the production lines, but large enough to validate the entire virtualization process. All the testbed line was created by using Huawei HW. First of all, the entire HW infrastructure was placed to form the testbed line, which was formed by three clusters. Then, on this HW, the SW needed to implement all the NFVs, such as vUSN, vUGW, DGW and CGW, was installed through virtualization tools. Subsequently, these NFVs were tested to validate its correct functioning. The tests that are used for SW validation, are listed in the Appendix C. To see more information about how the process of implementing this testbed line was, go to Chapter 5. The next step after validating the SW is to migrate a small number of users to this testbed line to ensure that everything works well without incident. During this process, the testbed line is continuously monitored, and analyzes are taken to check its performance. Once this validation has been carried out successfully. The rest of Vodafone’s production lines can be virtualized following the same steps mentioned above. Chapter 3 has more detailed information about how was the entire process of the virtualization project.. 2.7. G O TO THE M ARKET S TRATEGY. Vodafone deals in vertical business called Mobile Telephony. One of main Vodafone’s objectives is to ensure the loyalty of its customers by providing high-quality services. Vodafone will price its future products and services in a competitive way in order to beat its competitors. The main products and services are pre-paid, post-paid and Value-Added Service (VAS). The pricing strategy will be done differently for each segment that Vodafone targets, depending on its necessities. Therefore, each customer segments will be charged depending on the type of tariff that they have contracted. Besides, Vodafone will add products like mobile phones, to make the tariffs more attractive to the customer. Base on the quality of service, such as high speed, bandwidth, type of data traffic, the tariff price will be one or another, where the higher the quality of the service, the higher the pricing. However, the price campaign will also be adjusted taking into account the prices of the products and services of its competitors. Their services an products are sold through customer care centers, physical shops, online shop, and independent retailer shops. Furthermore, they have distributed across the country thanks to its strong distribution network. The way that Vodafone wants to sell these products and services are mainly based on advertising it. The idea is to make an aggressive marketing campaign, promoting the brand 15.

(26) CHAPTER 2. BUSINESSS PLAN through TV, press, prints, online, radio (Vodafone Yu program), and social media advertisements, among other channels. Additionally, Vodafone will promote its services and products through sports stars and celebrities in their advertisements to attract all kind of audiences. In fact, associate the brand with such stars, it is already demonstrated that increase the brand value. Once launched this campaign, Vodafone will keep track of the development of the campaign and it will investigate to determine how the campaign is perceived by consumers. As well as to know how is the satisfaction of the users using their products and services. For Vodafone, its highest priority is its customers, that is why it is very important for them to know how their customers’ satisfaction is. So, they can modify and improve their services as soon as possible, and thus always guarantee the best experience for their customers [19].. 16.

(27) 3 P ROJECT P LANNING In this section, all the project plan is explained. The purpose of this part of the thesis is to provide the reader with an overview of which were the activities that were carried out during the project. For it, the activities and their schedules will be described below, using the method Project Management Professional (PMP) of the Project Management Institute (PMI), which uses different tools, such as: Precedence Diagram Method (PDM) and Gantt chart. Moreover, the last part of the section will describe the budget scheme used, including some of the elements which are part of the CAPEX and OPEX of the project.. 3.1. T IME PLAN. In this section, the time plan of the project will be shown by using a type of bar chart called Gantt. The Gantt chart is a graphical tool used in project management, which uses bars to illustrate the expected dedication in time of different tasks over a given total time. First of all, the activities were listed in a generic way. That is not in indivisible activities, but in tasks that host other activities, see Figure 3.1. For example, let’s consider the duties involved in this proyect, which are: Test bed preparation, 5Tth Gi Line Legacy, vUSN and vUGW testing, Virtual Mobile Subscriber Equipement (vMSE) testing, vUSN and vUGW deployment, vUGW traffic migration, vMSE deployment, acvUSN and vUGW traffic migration, and vMSE traffic migration. Besides, to have more complete information, the most important milestones achieved during the realization of the project have been also added to this chart. The milestones are represented by starts, as it is possible to see in the right corner of the Figure 3.1. Although not all the activities mentioned above are going to be explained by this thesis, it is important to mention all of them. The idea is to provide the reader with an overview of the type of activities necessary to virtualize a core data network. For example, although this thesis will mainly talk about the vUSN and vUGW, vMSE was also developed in parallel. This node was not included in the thesis for lack of time, since, as it is possible to see in the time plan, most of its activities were planned to take place between August and October 2018. Below is a brief explanation of the most relevant activities of the project, indicating why the duration of each of them: 17.

(28) CHAPTER 3. PROJECT PLANNING Test Bed Preparation: Before virtualizing the production lines of the Vodafone network, tests were first carried out on a test bed line. For that reason, this testbed line had to be built, practically from the beginning. So, the number of activities that had to be done during this process were many: HW purchase, HW delivery, connectivity design, and HW installation and configuration. In addition, all the bureaucratic processes involved in each of the mentioned sub-tasks took also time into account. Therefore, taking into account all these reasons, the Test Bed Preparation was organized to finalize it into 16 weeks. To know information about the technical development of this activity go to Section 5.1 and 5.3. Testing vUSN & vUGW: During this duty, both nodes were tested in order to validate its software. The assigned time for this task was 9 weeks. To do all these tests it would be enough in 6 weeks. Nevertheless, taking into account that it was the first time the network was virtualized, it was decided to increase this number of weeks to 9. So, it would be enough time any unexpected in the case of finding errors. Deployment vUSN & vUGW: Once the correct functioning of the software has been verified, it is time to deploy these NEs in other locations in Spain to cover the entire Vodafone production network. This activity took one month. Two weeks for the deployment, and two weeks to check that everything worked well. Traffic migration: This last activity consisted of migrating all the users of the Vodafone legacy lines, to the new virtualized lines. This step is one of the most critical since any failure in the system is noticed by the users. All these activities mentioned above will have an explanation in greater detail, in Section 3.2.. 18.

(29) 19. CHAPTER 3. PROJECT PLANNING. Figure 3.1: Gantt Chart: Main Milestone..

(30) CHAPTER 3. PROJECT PLANNING. 3.2. P RECEDENCE DIAGRAM METHOD (PDM). In order to develop a schedule network diagram, which tracks all the activities involved in the project, it was carried out the table 3.2. This table was built using the PDM method based on the PMP certification. Each task or activity has their own duration and dates with their Early Start (ES), Late Start (LS), Early Finish (EF) and Late Finish (LF). All these dates are in weeks, taking as week 0 the first week of the project, right after the kickoff ended. Once the dates were determined, it was taking into account the delays that each task of the project can tolerate before the project comes in late. These delays are called Float, and it is calculated by subtracting the value from the LF with the value of the EF or by subtracting the value from the LS with the value of the ES. In both cases, the result should be the same value. Once the table was finished, it was constructed the diagram which was made using boxes/nodes and arrows. Here, each task was represented by boxes. In addition, each arrow showed the dependencies among these activities. Furthermore, the Duration and the Float of each task, are also represented. Thanks to this, after doing the representation, it is easy to realize which is the critical path of the project (in red), as well as the nearest path to the critical one (in grey). The resulting schedule network diagram is shown in Figure 3.3. Next, there are listed all the activities involved in the project, with a brief explanation of their aims: Task 1: Service Investigation. During this task, a broad investigation was carried out internally, as well as with the vendor. In it, some of the main topics where discussed: Design, elements, functionalities, Internet Protocol (IP)/Virtual Local Area Network (VLAN)s configurations, connectivity. Moreover, in order to introduce and share the solutions agreed upon at this stage, a kickoff was carried out, where both the vendor and the operator were part of this event. However, all this information was gathered in different manuals, so people could consult them at any time (it should be noted that not everything that was agreed at this stage was completed later. This was because during the project different decisions were made that caused changes in these previously agreed solutions). Task 2: High Level Design (HLD). In this step, a manual called HLD was created by Vodafone’s members. It explains the preliminary stages of the End-to-End (E2E) architecture that should be followed in order to develop the software products. Inside this manual, there is a NFV Overview, connectivity solutions, Virtual Evolved Packet Core (vEPS) details, and explanations of the different functionalities of the nodes involved in the project. Task 3: Connectivity Design. During this stage, several meetings were held in order to find out which connectivity option was the most suitable for the data core network of Vodafone Spain. The decisions were made mainly keeping into account the HLD previously developed, as well as features of the data core network. 20.

(31) CHAPTER 3. PROJECT PLANNING Task 4: Connectivity Demand. Once the connectivity design was done, the following step was to make the demand for the different IPs and VLANs necessary to carry out this design. Task 5: IP Configuration. After having the IPs and VLANs required, they were configured in each of the blades on its location. This configuration was carried out following the implementation manuals provided by Huawei. Task 6: LLD. Here, it was written the LLD, which describes the process step-by-step required by the software architecture of each of the nodes. It is based on the previous HLD design. This particular step was made by the Huawei, the vendor in charge of the virtualized elements. Task 7: Integration&Comissioning CSM (TR5). During this phase, the CSM was integrated and commissioned. This step is a critical task since the CSM is in charge of the management system for Huawei virtualization devices. It is important because, it is used to create, configure, activate and hang up the Virtual Machine (VM)s. Therefore, if this step fails, there is no way to continue with the project. Task 9: Integration&Comissioning VNF: vUGW & vUSN (TR5). Once the CSM was ready, the infrastructure was ready to do the integration and commissioning of the vUGW and vUSN. This task was carried out, following step by step the Huawei manuals for integration of the different elements of the network. In addition, it was taking into account the middleware to succeed between communications among applications. Task 10: TR5 Testing. This step is the first stage of tests that are performed on the nodes for their approval. In TR5, the performance of each node is tested, and with the results, the necessary changes are made to the software to improve it. Task 10.1: vUSN with release 18.1 TR5 Testing Task 10.2: vUGW with release 18.1 TR5 Testing Task 10.3: vMSE with release 18.1 TR5 Testing Task 11: TR6 Upgrade & Test. Once the nodes have passed the TR5 phase, several tests are carried out again to guarantee the correct functioning of each element. Some of the TR5 tests are repeated at this stage of TR6, with the purpose of placing the last patches on the nodes before launching them into production. Task 11.1: vUSN with release 18.1 TR6 Upgrade & Test Task 11.2: vUGW with release 18.1 TR6 Upgrade & Test Task 11.3: vMSE with release 18.1 TR6 Upgrade & Test Task 12: General Available (GA) Upgrade & Test. This is the GA phase where it is decided if the release of the nodes is ready to go into production or not. In the case of deciding that it is not ready, the last patches are made. 21.

(32) CHAPTER 3. PROJECT PLANNING Task 12.1: vUSN 18.1 GA Upgrade & Test. Task 12.2: vUGW 18.1 GA Upgrade & Test In order to understand better the different phases of testing, the following Figure 3.2 has represented in a visual way the different phases of the test, as well as certain activities that form them (notice that the VM1/Charter is the kickoff’s releases). In addition, Table 3.1 shows which kind of features and functions are available for test in the consolidated vUGW-Traffic Management Function (TMF) [13]:. Figure 3.2: Test availability CE18.1 TR5 vs.TR6 vs. GA [13].. CE18.1 TR5 • • • • • •. CE18.1 TR6. TCP Optimization MW3 CUBIC Header Enrichment Normal header enrichment Vodafone start. • • • • • • •. TrafficSteering MSP(VO,WO) CleanPipe ACRheaderenrichment CloudPRS TCP Optimization BRB. CE18.1 GA • • • • •. TrafficSteering IWF IWF function Static Function Dynamic function (TBC). Table 3.1: Huawei Testeing Phases for vUGW-TMF.. Task 13: vBOM & pBOM. These two activities consist of elaborating documents where all the technical features of the elements that will be necessary for the implementation of the nodes will be detailed. The Virtual Bill of Materials (vBOM) is the first to be made. It contains the specifications of the virtual elements, such as the VM types, the number of VMs required, the number of interfaces for each VM, vCPU, RAM, affinity rules, among others. Once this document is done, the Physical Bill of Materials (pBOM) is implemented, where the physical elements necessary to contain all the parameters indicated in the vBOM are found. For example, the number of blades per node. Task 14: Hardware Purchase. To carry out this duty, a document with detailed information about the purchase has to be prepared. In it, the prices of each HW element that is going to be purchased are broken down, as well as the total price of the purchase. This document is sent to Vodafone members in charge of evaluating the budget, and 22.

(33) CHAPTER 3. PROJECT PLANNING therefore accepting or rejecting it. In the case of being accepted, the purchase of the HW can begin, directly by contacting the suppliers. Task 15: Hardware Delivery. This phase consists of the time necessary to receive the previously purchased HW. Task 16: Hardware Integration. Once the HW has been received, it can be installed. This procedure is done by integrating the new HW to the old infrastructure already installed. Task 17: TR6 First of All First Offial Application (FOA). Once the HW was integrated, it is initiated the FOA of each of the NEs. This phase consists in migrating a small number of users to the line, from a small area of Spain. The performance of the network will be monitored for two weeks. If all goes well, the rest of the users will be migrated after this trial period. Task 17.1: vUSN 18.1 TR6 FOA Task 17.2: vUGW 18.1 TR6 FOA Task 18: vUGW Traffic Migration. This is the last activity before considering the node is completely integrated with the core. This step consists in migrating all the users who were using the legacy data core network, to the new virtualized data core network. This is a critical process since any failure could be noticed by users. That is why, it is done step by step in two weeks, to avoid errors in the network and control their behaviour. Once all the migration of the users has been completed, it just left maintaining and monitoring the node to avoid anomalous behaviour or solve possible incidents.. 23.

(34) CHAPTER 3. PROJECT PLANNING. Activity Task 1 Task 2 Task 3 Task 4 Task 5 Task 6 Task 7 Task 8 Task 9 Task 10. Task 11 Task 12 Task 13 Task 14 Task 15 Task 16 Task 17 Task 18. Dedcription. Duration (weeks). ES. LS. EF. LF. 2 3 4 2 2 1 2 3 1 6 6 6 2 2 2 1 1 3 4 4 4 2 2 2. 0 2 5 9 11 13 14 14 16 17 17 17 23 23 23 25 25 9 12 16 20 27 26 28. 0 2 5 9 11 13 14 14 16 17 17 17 23 23 23 25 25 10 13 17 21 27 26 28. 2 5 9 11 13 14 16 16 17 23 23 23 25 25 26 26 26 12 16 20 24 29 28 30. 2 5 9 11 13 14 16 20 17 23 23 23 25 25 26 26 26 13 17 21 25 29 28 30. Service Investigation HLD Connectivity Design Connectivity Demand IP Configuration LLD I&C CSM (TR5) I&C U2000 (TR5) I&C VNF: vUGW & vUSN (TR5) Task 10.1 vUSN 18.1 TR5 Testing Task 10.2 vUGW 18.1 TR5 Testing Task 10.3 vMSE 18.1 TR5 Testing Task 11.1 vUSN 18.1 TR6 Upgrade & Test Task 11.2 vUGW 18.1 TR6 Upgrade & Test Task 11.3 vMSE 18.1 TR6 Upgrade & Test Task 12.1 vUSN 18.1 GA Upgrade & Test Task 12.2 vUGW 18.1 GA Upgrade & Test vBOM & pBOM Hardware Purchase Hardware Delivery Hardware Integration Task 17.1 vUSN 18.1 TR6 FOA Task 17.2 vUGW 18.1 TR6 FOA vUGW Traffic Migration. Table 3.2: PDM activities schedule.. 24.

(35) 25. CHAPTER 3. PROJECT PLANNING. Figure 3.3: Precedence Diagram.

(36) CHAPTER 3. PROJECT PLANNING. 3.3. B UDGET. This section will expose the most important economic factors that were taken into account to make the decision to virtualize the Vodafone’s data core network. The data shown below comes from the budget proposal offered by Huawei to Vodafone. Since the data core network was virtualized with products of this company. In order to keep confidentiality, note that all the data that is going to be exposed below is not the real one but approximations. First, the budget of a hypothetical project scenario will be presented. In this scenario, the data core network is not virtualized. Secondly, a scenario with the data core network virtualized will be shown. So, knowing both scenarios, it will be very easy to compare them to see which is better. Figure 3.4 shows the cumulative values for the next five years of the two scenarios mentioned above. In this graph, it is possible to see that as the years go by, the difference between "Doing nothing" and virtualizing, is increasingly noticeable. In fact, this difference reaches 10 million euros in the fifth year. Furthermore, after these first five years, the forecast is that this budget difference will continue to increase, saves a lot of money in Vodafone. This big difference is mainly due to the fact that the initial investment that has to be made in HW and SW for virtualization, is much less than what should be done in HW in the "Do nothing" scenario. Besides, the maintenance required by this HW equipment is very expensive, so that having less amount of HW in the virtualization scenario, these OPEX costs are very low.. Figure 3.4: Comparison between “Do nothing” scenario vs. Virtualization.. All the data shown in the previous graph, are taking into account all the elements of the data core network necessary to implement all its functionalities. However, the following data will show only those values that are related to this master thesis, ignoring the rest. Therefore, the total costs will be lower. 26.

(37) CHAPTER 3. PROJECT PLANNING In order to have more details of how the budgets of the previous scenarios are composed, Figure 3.6 and Figure 3.5 show the CAPEX of "Do nothing" scenario and Virtualized scenario, respectively. The first detail that can be highlighted is that for the "Do nothing" scenario, more elements have to be contemplated than for the virtualized one. This is mainly due to the HW that is used, as well as the complementary elements that this HW needs. Another fact to take into account, is that in the virtualized scenario, although the costs of professional services are more expensive at the beginning, with the years are cheaper, being a value well below than the other scenario. In addition, in virtualized environments, there are no added costs for Operation Support System (OSS) licenses, when in the other scenario there are. With all this, the costs generated by a non-virtualized scenario would amount to 21.474 k". Nevertheless, virtualizing the network would be 16.492 k". The difference that exists between the two cases, as it was shown previously, will be increasing. So it is clear that use a virtualized environment is much more economical.. Figure 3.5: CAPEX Virtualization detailed - Unitary cost k".. 27.

(38) CHAPTER 3. PROJECT PLANNING. Figure 3.6: CAPEX "Do Nothing" detailed - Unitary cost k".. 28.

(39) 4 T ECHNICAL B ACKGROUND Vodafone’s legacy network is a non-centralized network, where each of its NEs are built in different HW, see Figure 4.1. Although this HW is very sophisticated, every time it is needed to add a new functionality to the network, a big investment in HW has to be made. As a result, this kind of networks have a high cost and in the long term, they are not profitable. Besides, the nodes do just one function per entity, which makes the network less flexible and inefficient. As it was shown in previous chapters, the world of telecommunications is constantly evolving and customers expectations are constantly growing. Therefore, it is necessary to adapt the network to these new needs. This chapter will give an overview of some key concepts to understand how important is to use virtualization for future 5G networks. The chapter is divided into three parts. First, The techniques needed for virtualization will be explained in detail (e.g. NFV and SDN). Secondly, the new virtual network architecture in Vodafone will be introduced by explaining the most important elements and services. And finally, an introduction to the 5G networks will be made, where the most significant technologies will be explained (e.g. MEC, CUPS, NSA and SA networks, and network slicing).. Figure 4.1: Old Vodafone’s Topology. 29.

(40) CHAPTER 4. TECHNICAL BACKGROUND. 4.1. T ECHNIQUES FOR VIRTUALIZATION. Virtualization is the technology that allows sharing capabilities of physical storage, computing and network by dividing these resources among different VMs. The first time that the concept of VM appeared was in 1964 [24] with IBM. Nowadays, there are many virtualization techniques that all to support the execution of operating systems in VMs (e.g. NFV and SDN), [24]. Following, two techniques used for virtualization will be presented in this chapter.. 4.1.1. NFV. Figure 4.2: NFV Basic Architecture [7].. In general terms, NFV is a new network architecture concept which uses technologies to virtualize NEs and connect them in order to create network services an applications. Therefore, thanks to NFV it is possible to redefine the way of delivering and operating the network functions. Some of the technologies used by NFV are standards IT and cloud technologies. With them, NFV can create a new architecture, where network functions, as well as the applications, are entities create by only using SW. In addition, these SW entities are independent of the HW and use resources like, network, compute and storage elements as the HW platform. Moreover, with this new architecture, it is possible to develop new SW functions and applications in an easy way. Hence, there are more vendors which can implement new functions and application. This translates into a more diverse ecosystem of vendors in 30.

(41) CHAPTER 4. TECHNICAL BACKGROUND comparison with the legacy architecture. Besides, NFV brings innovation and with this, new business opportunities through the new services that can be provided to the customers. Furthermore, NFV is able to optimize the resources of the network, so there is a reduction of the CAPEX and OPEX needed. All the advantages that NFV provides, made Vodafone decide to use this new technology and modernize its data core network. Therefore, Vodafone is consolidating functions of its NEs, reducing the number of HW platforms. For instance, if it is compared to the old Vodafone’s architecture (Figure 4.1) and the new one (Figure 4.4), the number of nodes has decreased. This is because the new vUGW has integrated more functions as the old Unified Packet Gateway (UGW) had (see more information regarding this topic by going to the following Subsection 4.2.1). With this, Vodafone is improving its cash flow and providing better services to their customers, [12], [7]. Figure 4.2 has the NFV architectural framework, with its four main areas, [32]: • OSS and Business Support System (BSS) These two systems work together in order to support network services. In previous versions, OSS and BSS were entities more separates. However, since the services are more and more complex, these two entities have needed a closer liaison between them. OSS and BSS are structures with technology-oriented to include new services into the network. These services are built using Service Fulfillment Functions (SFF) that is in charge of the service design and resources provisioning, and Service Assurance Functions (SAF) that handle the assurance processes (e.g troubleshooting). Nowadays, these new processes carried out in the OSS, are compatible with the new NFV and SDN technologies. • VNFs A VNF is a virtualized version of a traditional network function which is implemented by SW simulating functions built in HW. Some examples of VNF are the vEPC and the components that form it: Mobility Management Entity (MME), vUSN, vUGW (formed by Packet Data Network Gateway (P-GW) and Serving Gateway (S-GW) platforms), and firewalls, among other elements. The main idea is to implement this virtual platforms in the core by using the lowest possible number of HW and running it over the NFVI. This is possible since VNF can be implemented as a VM or multiple VMs, or even as a function implemented within a shared VM. • Virtual Network Functions Infrastructure (VNFI) This subsystem consists of all the HW (e.g. physical servers, storage, and networking) and also SW (e.g. virtual servers, storage, and networking) components on which VNFs are deployed. In addition, it includes the compute, storage, and networking resources, as well as the associated virtualization layer called hypervisor and the container which holds the VMs. 31.

(42) CHAPTER 4. TECHNICAL BACKGROUND The hypervisor is an operating system, which provides a level of abstraction. It abstracts the host infrastructure and allows to use it as a pool of virtual resources. Therefore, all the virtual resources can be consumed by VMs. Therefore, the hypervisor is one of the most important components in virtualization. • Management and Orchestration (MANO) It provides orchestration and lifecycle management for the virtualized resources of the NFVI and the VNFs. Inside this subsystem, there are three functional blocks together, which are: Virtualized Infrastructure Manager (VIM), NFV Orchestrator (NFVO), and VNF Manager (VNFM). All these blocks allow communication between NFV and MANO. – VIM is a management system which controls and manages the compute, storage, and network resources of the NFVI. The following description gathers some of the main VIM activities: Resource management, where it is included in the management of the SW inventory, hypervisors, and the virtual compute, storage and network resources. In addition, it allocates resources, as well as assigns dynamic resources and power. Another key activity is the operations management to visualize and manage the NFVI, and data collection. – NFVO manages networks services that include multiple VNFs. It is able to create end-to-end services using several VNFs. In addition, it also manages the lifecycle of Network Services. During this VNFs lifecycle, there are some key activities like: Onboarding a network service, instantiating a network service, scaling up or down a network service, and updating a network service. – The VNFM is an entity which is in charge of the management and operation of the individual VNFs. Normally, this management is focused on Fault, Configuration, Accounting, Performance, and Security (FCAPS). However, currently with the network virtualization, there are more features of managing the lifecycle of the VNFs. Some of its tasks are the following: * Creation of VNFs by the use of templates and parameters. * Increase or decrease the capacity of these VNFs by scaling up or scaling down. * Update and upgrade VNFs. * Finalize the VNFs and returning them to the NFVI resoruces pool.. 4.1.2. SDN. SDN is a set of techniques used for network transformation since it can face the new challenges and changes that are appearing in the network area. Thanks to SDN, it is possible to manage, control, optimize, arrange and distribute the network resources. In addition, one of the basic ideas of SDN is the separation of the architecture in two traffic planes: One for signalling and another for data. This makes SDN a centralised network architecture. 32.

(43) CHAPTER 4. TECHNICAL BACKGROUND Another basic idea with regard SDN, is the capacity it has of abstract the network infrastructure from the applications. Thanks to this, SDN allows having a new logical-centralised control system which is programmable and makes the network architecture more dynamic and scalable. Besides, it is not necessary to buy new HW, since the existing one can be configured and programmed. Hence, SDN is also cost-effective, reducing the overall costs. In general terms, the principles of SDN are: • Separate user plane from control plane. • Standard protocols for interoperability. • Create an open platform. • Apply network wide. SDN can be divided in two main areas, as it is shown on Figure 4.3: SDN Application layer, SDN Controller. The most important part of those mentioned above is the Software Defined Network Controller (SDNC) cluster, which is the controller in charge of deciding where and when sending the control flow and data flow. These flows which go through the SDNC, can be divided into three sections: 1. Real-time network status. 2. Service demand. 3. Automated provisioning of physical network nodes. SDN provides a visibility of the real-time status of the traffic-flows as well as the network resources. When the SDN controller notices there is a new service demand, it can automatically provision the whole network resources E2E. Furthermore, the centralised controller is able to optimise the paths for all the services and compute the network taking account the optimal view that it as calculated, [22]. Vodafone has introduced SDN in theIP/Multiprotocol Label Switching (MPLS), Optical and Microwave transport domain. For it, Vodafone had to define the SDN for single Transport Network architecture. In addition, Vodafone is currently introducing SDN over the NFV network. As a result, it was obtained an improvement in the current network assets thanks to automation and resource optimization. In addition, it has also facilitated the design, delivery and operation being dynamic and scalable. To summarize, the following list has an overview of the main reasons why Vodafone is using this SDN technique, [7]: • Introduce programmability and maximise automation. • Optimise transport resources usage. 33.

(44) CHAPTER 4. TECHNICAL BACKGROUND. Figure 4.3: SDN general structure [7].. • Dynamic centralized decisions based on the E2E network view. • Full coordination among the inter-layers. • Dynamic establishment of various services according to demand. • Better performances and resiliency. • Real-Time view and decision making (monitoring, analytics, and optimisation, among others). • Easy and fast way to add new features and capabilities.. 4.2. V IRTUALIZED N ETWORK A RCHITECTURE AND S ERVICES. This section is aimed at describing the new Vodafone virtualized network elements, as well as its functionalities. Besides, there will also be a brief introduction to the services that Vodafone offers to its users, to better understand how the Vodafone network works.. 4.2.1. V EPC. E LEMENTS. The new vEPC brings the possibility of consolidating functions in the same NE. Therefore, the final network architecture has less number of NEs than the old Evolved Packet Core (EPC), Figure 4.4 has represented the new vEPC. Specifically the vEPC is composed by two new nodes, vUSN and vUGW, which will be presented later. 34.

(45) CHAPTER 4. TECHNICAL BACKGROUND. Figure 4.4: New Vodafone’s Topology. Although vUGW and vUSN are new virtual platforms with new functionalities, no interface changes with respect to the legacy architecture. Furthermore, they are based on the same 3GPP standard in which was based on the old network. Figures 4.5 and 4.6 have the structure of how is the vUSN and vUGW integration with the rest of the network, as well as their interfaces. Moreover, the Table 4.1 gather not only the NEs which are integrated with the vUSN and vUGW, but also the application layer protocol and the transport layer protocol, that each interface uses. • vUSN: In the current virtual network architecture, the vUSN is a triple access node, and it carries out the functionalities of the old Serving GPRS Support Node (SGSN) and the MME. The following VMs are needed to implement this NFV: – Operating and Management Unit (OMU)s: which are in charge of operations and management of the NFV. (Scheme 1+1). – Session Data Unit (SDU)s: which implements session context storage functions. (Redundancy scheme N-way). – Service Processing Unit (SPU)s: which carries out processing and GPRS Tunneling Protocol (GTP)-U transfer functions. (Redundancy scheme N-way). – I/O Processing Unit (IPU), which deploys IP routing and session dispatching functions. (Redundancy scheme N-way). – Gb Interface Processing Unit (GBU): which deploys protocol functions in 2G. (Redundancy scheme N-way). – Signal Interface Process Unit (SIU): which implements processing and GTP-C functions. (Redundancy scheme N-way). 35.

(46) CHAPTER 4. TECHNICAL BACKGROUND. Figure 4.5: vUSN (SGSN/MME) Standard Interfaces.. NE. vUSN. Peer NE. Interface. Application layer protocol. Transport layer protocol. HLR HSS eNodeB BSC. Gr S6a S1-MME Gb IuPS-CP IuPS-UP Ga S10/Gn S11/Gn SGs Sv S1-U IuPS-UP (Direct Tunnel) Ga Gx Gy Gi/SGi S11/Gn S5. SS7 Diameter S1AP BSSGP RANAP GTP GTP GTP GTP SGsAP GTP GTP. M3UA/SCTP SCTP SCTP IP M3UA/SCTP UDP UDP UDP UDP SCTP UDP UDP. GTP. UDP. GTP Diameter Diameter Radius GTP GTP. UDP TCP/SCTP TCP/SCTP UDP UDP UDP. RNC CG vUSN/Legacy USN vUGW/Legacy UGW MSC eNodeB RNC. vUGW. Figure 4.6: vUGW (GGSN/S-GW/P-GW) Standard Interfaces.. CG PCRF OCS AAA vUSN/Legacy USN vUGW/Legacy UGW. Table 4.1: vEPS Network Element Interconnect Relationship [35].. 36.