IEEE Press
445 Hoes Lane
Piscataway, NJ 08854
IEEE Press Editorial Board
Tariq Samad, Editor in Chief
| Giancarlo Fortino | Xiaoou Li | Ray Perez |
| Dmitry Goldgof | Andreas Molisch | Linda Shafer |
| Don Heirman | Saeid Nahavandi | Mohammad Shahidehpour |
| Ekram Hossain | Jeffrey Nanzer | Zidong Wang |
Copyright © 2017 by The Institute of Electrical and Electronics Engineers, Inc. All rights reserved.
Published by John Wiley & Sons, Inc., Hoboken, New Jersey.
Published simultaneously in Canada.
No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permission.
Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.
For general information on our other products and services or for technical support, please contact our Customer Care Department within the United States at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002.
Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic formats. For more information about Wiley products, visit our web site at www.wiley.com.
Library of Congress Cataloging-in-Publication Data is available.
ISBN: 978-1-119-31485-1
To Diego
If there had been any doubt that our global society has moved into a digital century, it has surely been dispelled by the dramatic adoption of mobile phones now estimated to reach 4.6 billion subscribers, some of whom having more than one mobile. As to the so-called “smartphones,” there are estimated to be about 3 billion subscribers to these devices. These numbers will almost certainly increase as the “Internet of Things” evolves and the associated devices begin to populate residential and enterprise operations at paces comparable to the mobile phone influx of the past decade. Already very dependent on devices linked to the Internet and the services they offer or rely upon, it seems predictable that our dependency will grow and that our vulnerability to buggy software or malware will increase.
There are many implications of this observation. The first is that we will need to prepare for a fragile future and that we need the makers of these devices and their software to be extremely thoughtful and careful to avoid major vulnerabilities. Second, we will need to update software in these myriad devices in a way that is secure and ensures with high probability that a valid update has been recorded. Third, we will be faced with configuring increasing numbers of devices and we need to make this process as simple, painless, and reliable as possible, especially as they change hands with people moving from place to place and inheriting or taking their many devices with them. Fourth, we will need to stay highly cognizant of the potential hazards to privacy that these programmable devices pose. Even simple information such as room temperature taken every few minutes might be useful for ascertaining whether people are present and where they are. At the least, a record of temperatures could reveal how many family members there are, what rooms they prefer, and when they might be away. Many other scenarios can be fashioned that highlight these risks and remind us that not all technology results in positive outcomes.
At the same time, we would be remiss not to speculate about the rich potential of artificial intelligence to smooth our interactions with a world populated with software-filled cyber-physical systems. Incredible advances have been made in the past decade with natural language processing, text to speech production, speech recognition, logical reasoning about the real world, image and sensor understanding, robotics, and navigation. Artificially intelligent assistants are becoming more common and more useful as they gain ability to communicate with each other, with computer-based systems and with the humans they serve.
It seems reasonable to anticipate that the human thirst for knowledge itself will be augmented increasingly by the use of pattern-recognizing software systems to the point that some aspects of discovery may be attributed to artificially intelligent programs that will sift vast amounts of data looking for correlations and anomalies adding to the sum of human knowledge. Whatever else the twenty-first century may bring, it will be a time of rapid innovation and discovery, rivaling centuries of the past and casting light into the future.
Finally, one cannot help but be concerned about the preservation of the vast quantities of digital information that will be produced in the decades ahead. Digital media have uncertain lifetimes and the interpretation of binary information often requires specific, executable software to render the meaning of any preserved bits. Software that runs now may not run on future machines and future operating systems, leaving us with vast quantities of “rotten bits.” Forestalling a potential digital dark age will be another of the challenges that lie ahead as we fashion a future filled with new digital services upon which our society will depend.
Vinton G. Cerf
This textbook is targeted to postgraduate or advanced undergraduate students. Gone are the days when voice was the only telecommunications service. In the current digital world, broadband and wireless networks enable multiple services, which are continuously evolving. Therefore, an updated textbook is needed that presents the rapidly evolving communications infrastructure to date and the exciting services that it supports. This is drastically different from the old style books on the telco infrastructure focusing on telco-centric network and services such as PSTN or B-ISDN.
This book presents the main products and services that are provided by current digital providers (Information and Communication Technologies players, including Internet behemoths, telecommunications operators, etc.). It covers services such as enriched communications, fixed and mobile broadband, financial services for unbanked in emerging markets, Pay TV, data communications for machines (also known as Internet of Things), digital home, and so on. This book is a complete and structured compendium of successful digital services with illustrative examples.
It should be stressed that this book's focus is on services paid for by customers (i.e., not those subsidized with advertising like social networks), but not the underlying technologies or internal capabilities to offer them that are not directly perceived by customers (therefore, out of scope are important topics of network management or a deep dive into future network technologies like Software Defined Networks and Network Function Virtualization, the future 5G networks, Fog computing architectures, etc.).
As opposed to technical-only textbooks, all topics in this book are addressed by taking into account the reason why customers demand the service, as well as the strategic and business perspective of how players can leverage competitive advantages to provide those services, that is, the underlying consumer and economic dynamics that determine the success or failure of service offerings.
By doing so, readers can get a better understanding of the key services in the highly dynamic Internet and telecom industries. They can get a holistic view of the main services from a strategic perspective. These up-to-date new areas have become extremely dynamic, and is still subject to continuous change.
The book is structured around six sections, each composed of one or more chapters, as follows:
Antonio Sánchez
Belén Carro
Our gratitude to all the people who have made this book possible. First of all, to the contributors who have helped with some of the chapters. Also, to the publisher (particularly Mary Hatcher and Divya Narayanan for their support) and the IEEE for giving us this opportunity. In addition, the reviewers who provided feedback to improve, at both the proposal stage and during the writing of this book.
Voice is the most pervasive telecommunication service, particularly mobile voice, with 4.7 billion unique mobile subscribers as of April 2016,1 out of a total 7.8 billion mobile connections. Legacy circuit switched voice still accounts for majority of world telecom customers; however, voice-over IP is finally starting to replace it. Voice-over IP technologies such as H.323, Session Initiation Protocol (SIP), and voice codecs including wideband, carrier grade infrastructure known as IMS-IP Multimedia Subsystem2 have been available for more than a decade, but deployment of All-IP access networks (FTTH (Fiber-to-the-Home) and LTE (Long-Term Evolution)) has been the trigger for their adoption. Only in the enterprise segment, the legacy PBX systems have initiated the migration earlier. In fixed networks, initial FTTH deployments maintained simultaneous use of legacy copper for voice. In 4G mobile networks, fallback to 2G/3G for voice has been a temporary patch until VoLTE deployment in the network and progressive availability of enabled devices. HD Voice is included in VoLTE, but is also available in 3G networks without VoIP. Voice-over WiFi is emerging as a complement mainly for zones with poor cellular coverage.
Voice has been the dominant, or even only, telecommunications service for decades. The possibility of talking to people in remote places has been, and still is, a killer application. It has substituted more primitive means to communicate, both non-real-time and real-time. Furthermore, the convenience of talking wherever you are, thanks to the more recent mobile telephony that has certainly surpassed the success of fixed telephony, allows one to communicate in more remote areas without terrestrial infrastructure.
The penetration of FTTH subscribers is still nascent; for example, in Europe there were almost 36 million (including Fiber to the Building) in Europe at the end of September 2015.3 This has triggered the adoption of voice-over IP in fixed lines, although initial FTTH deployments supported simultaneous use of legacy copper for voice. Typically, the FTTH customer premises equipment, Optical Network Terminal (ONT), includes a voice port (RJ-11 connector) that interfaces with the legacy internal copper network or directly with the legacy telephony terminal. The usage is transparent for customers, since they make and receive calls normally with their legacy endpoints. The FTTH device includes a gateway that converts analog telephony into voice-over IP, which in turn is connected to the VoIP infrastructure of the operator.
Voice-over LTE is the name given to the technology that provides telephony to 4G customers. It is based on voice-over IP, since LTE gets rid of circuit switched voice. In order to guarantee voice quality, VoLTE traffic is prioritized versus other kinds of traffic, which is also IP. Initial LTE deployments did not include VoLTE support, resorting to Circuit Switched FallBack (CSFB), which is based on disconnecting voice from the 4G network and connecting it to a legacy network (3G or even 2G) to establish the voice call. Once the call is finished, 4G connection can be set up again.
As of the end of the first quarter of 2016, there were 58 operator launches, in 32 countries,4 with 228 end user devices. This was still a relatively small percentage of the total number of LTE networks: 467 operators in 153 countries, reaching 48% of the population. As could be expected, these countries are mainly in Europe, North America, South East Asia, and Oceania:
It can be seen that all major mobile telecommunication groups in the world have launched VoLTE in at least one market. Among the exceptions are
However, it has to be noted that as of April 2016, there were already 126 operators investing in VoLTE deployments, trials, or studies in 60 countries.8
In terms of adoption, the operator that is most further along is probably AT&T, which launched in mid-2014, and as of the end of 2015, has more than 27 million VoLTE subscribers (the highest in the United States), and has a coverage for 295 million Americans.9
In November 2015, South Korea became the very first country to provide commercially interoperable VoLTE service among operators.10 Before this milestone, customers could only enjoy the superior quality of VoLTE when calling other customers of the same operator. There are three operators (KT, SKT, and LG Uplus) with around 35 million VoLTE-enabled subscribers that are fully commercially interoperable. By that time, South Korea has marketed 90 different models of VoLTE-enabled handsets in the country. It has to be noted that the three operators were also the first in the world to launch their respective standalone services in December 2012, with the next country launching in May 2014 only.
Also a Korean operator achieved another major world milestone in terms of interoperability—in this case, an international roaming service. At the end of 2015, South Korea's KT and Japan's NTT DOCOMO offered a bilateral VoLTE roaming service. Previous milestones were unilateral (e.g., Korean LG Uplus with Japanese KDDI). Other mobile network operators involved in VoLTE roaming trials include China Mobile, KPN, SK Telecom, and Verizon Wireless.11
In terms of end user devices, the number includes carrier and frequency variants. As of June 2015 (219 VoLTE capable out of 3253 LTE devices), 198 smartphones had been announced by all the leading vendors, including Apple, Asus, Fujitsu, HTC, Huawei, LG, Motorola, Pantech, Samsung, Sharp, and Sony Mobile.12
Voice-over WiFi (VoWiFi) is the term used by operators in order to refer to the provision of telephony services over a WiFi access. From the user perspective, the experience is similar to VoLTE, or traditional voice, that is, just call and answer. However, from the network perspective, it is quite different, since the WiFi network is not an integrated part of the mobile network. And therefore, the quality of the call can be poorer, and in general similar to that of over-the-top (OTT) applications.
Compared to VoLTE, the number of VoWiFi launches is much more limited, just 18 operators in 11 countries, by the end of March 2016. Also, deployments have been much more recent, starting only in September 2014 (in the United States by T-Mobile/Deutsche Telekom). In the United States, all four major operators have launched VoWiFi by now. Other countries with more than one operator include the United Kingdom, Switzerland, Hong Kong, and Canada. The remaining markets are China, Czech Republic, Denmark, Liechtenstein, South Africa, and Thailand. It has to be noted that most operators that have launched VoWiFi in a given market have also launched VoLTE in the same market. An exception is Sprint (Softbank) in the United States.
There have been operators that have launched VoWiFi service, without integrating it tightly with the VoLTE/IMS infrastructure and devices. One example is Telefonica in the United Kingdom and Latin America, with its service TU (formerly TU Go) that can be considered a pioneer in the world (perhaps together with Rogers in Canada), since it was launched in the United Kingdom in March 2013 (and afterward in Argentina, Peru, Brazil, and Colombia).13 In the first quarter of 2016, it announced the integration with iPhone's native WiFi calling feature in Brazil.
Another announcement worth mentioning is the collaboration between Google and mobile network operators (19 major ones) in the field of Rich Communications Suite (RCS). Google will provide the user experience for Android devices (including an open-source version of the client), initially for messaging, but with support for advanced calling features, which among other things also include calling over WiFi, in the future.14
High-Definition voice provides superior voice quality based on wideband codecs, which (as opposed to legacy telephony) include more frequencies (bandwidth) of the analog sound (legacy narrowband reaches 3 kHz, whereas human voice reaches 14 kHz). HD voice has been available for quite long time, for both voice-over IP applications and circuit switched telephony (particularly mobile, even before 4G, with 3G and even 2G15). Therefore, the number of commercial services is more widespread, with 162 operator launches in 89 countries as of the end of the first quarter of 2016, including VoLTE deployments.
The term “over-the-top” refers to services that are offered independent of the underlying network. One of the most prominent consumer over-the-top applications for PC has been Skype, which is now part of Microsoft. In January 2016, the company reported that Skype has over 900 million downloads on iOS and Android.16 It also has an enterprise counterpart, called Skype for Business, with a major update released in December 2015, including voice telephony without PBX, and online meetings for up to 10,000 participants.
Perhaps the most prevalent over-the-top application for mobile is WhatsApp,17 which was started in 2009. In early 2014, WhatsApp was acquired by Facebook for $16 billion ($4 billion in cash, and around $12 billion in shares).18 In February 2016, it reached the astonishing milestone of 1 billion monthly active users, although it has to be noted that its predominant usage is for messaging. It is worth mentioning that WhatsApp was an inexpensive app, but in early 2016 the company announced that it was becoming free, that is, no longer charging any subscription fees; its usage is also free in free WiFi networks, but of course it consumes data allowance if used with mobile broadband. The company also confirmed that it will not include advertising to subsidize its costs, but rather test business models around commercial messages (communications with businesses). In April 2016, it included end-to-end encryption for all the information exchanges, including voice. The app is available for iOS, Android, and Windows Phone. By the end of 2016, it will end its support to minority or legacy operating systems like BlackBerry, Nokia S40/Symbian S60, as well as older versions of Android 2.1 and 2.2 and Windows Phone7.1. In the first quarter of 2015, WhatsApp started rolling out voice-over IP calls, progressively in different operating systems; this feature was already available in Facebook Messenger application, which by then accounted for more than 10% of mobile VoIP calls globally according to the company.19 By mid-2016, 100 million voice calls per day were made through WhatsApp.20
| 2G | 2nd Generation |
| 3G | 3rd Generation |
| 4G | 4th Generation |
| CSFB | Circuit Switched FallBack |
| FTTH | Fiber-to-the-Home |
| HD | High Definition |
| IMS | IP Multimedia Subsystem |
| IP | Internet Protocol |
| LTE | Long-Term Evolution |
| ONT | Optical Network Terminal |
| OS | Operating System |
| OTT | over-the-top |
| PBX | Private Branch Exchange |
| RCS | Rich Communications Suite |
| RJ | Registered Jack |
| SIP | Session Initiation Protocol |
| VoIP | voice-over IP |
| VoLTE | voice-over LTE |
| VoWiFi | voice-over WiFi |
| WiFi | Wireless Fidelity |