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IPTV and Internet VideoExpanding the Reach of Television Broadcasting
By Wes Simpson Howard Greenfield
Focal PressCopyright © 2009 Elsevier Inc.
All right reserved.
Chapter OneWhat Is Internet Protocol, and Why Use It for Video?
Nothing is really real unless it happens on television. Daniel J. Boorstin, American social historian and educator
Before we try to define Internet Protocol (IP) and why it is a good solution for video, it's appropriate to consider what may be obvious—that video transport over IP networks is not only here today, but is poised to further dominate video service delivery for many years to come. As this occurs, new media communications services that can only be imagined will continue to arise along with it. We are at the dawn of what may be the most fascinating phase in broadcasting history.
We will discuss the reasons more in this chapter, and the spread of IP will form a subtext throughout the rest of this book. However, there is little doubt that a large and vigorous market continues to develop though a confluence of improved compression, faster data links, more sophisticated software, and evolving viewer habits. So, let's explore these trends then see how they impact network, technology, and business decisions today. Later, in the final chapter, we'll look at where these trends are likely to lead us in the decades ahead.
Digital video is a precisely timed, continuous stream of constant bit rate information, which commonly works on networks where each signal is carried over a channel that is purpose-built for video. In contrast, IP networks carry many different kinds of data from a huge variety of sources on a common channel, including e-mail, Web pages, instant messaging, voice over IP (VoIP), and many other types of data. With all of these data flowing together, the Internet is, at best, a loosely timed collection of information that is broken up into discrete packets. Clearly, IP and video don't make an ideal marriage of technologies.
Despite this fundamental incompatibility, the market for IPTV and Internet video is exploding. Why? Well, the answer to that question boils down to five basic arguments.
Because broadband IP networks reach so many households in developed countries, video service providers can use these networks to deliver video services without having to build their own networks.
IP can simplify the task of launching new video services, such as interactive programming, video on demand (VOD), and targeted, viewer-specific advertising.
The cost of IP networking continues to decline due to the massive volume of equipment produced each year and the existence of worldwide standards.
IP networks can be found in every country in the world, and the number of users with high-speed Internet connections continues to grow at a rapid pace.
IP is a perfect technology for many other applications, including data transactions (such as e-mail or banking), local area networking, file sharing, Web surfing, and many others.
This chapter begins with a brief summary of the market trends for IPTV and Internet video. It then discusses in greater depth the five forces mentioned earlier that are driving the migration of video into IP, followed by a look at some issues that need to be addressed by any system or organization trying to send video over an IP network. The chapter concludes with a case study of a successful IPTV network installation.
The Internet Protocol
Internet Protocol provides a mechanism for directing packet flows between devices connected on a network. IP is a common protocol used throughout the Internet and any of the millions of other networks that use IP. Without IP, chaos would reign because there would be no way for one device to send data specifically to another.
At its heart, IP is a standard method for formatting and addressing data packets in a large, multifunction network such as the Internet. A packet is a unit of information (a collection of bytes) in a well-defined format that can be sent across an IP network. Typically, a message such as e-mail or a video signal will be broken up into multiple IP packets. IP can be used on many different network technologies, such as Ethernet LANs, long-haul fiber optic and telephony networks, and wireless Wi-Fi links.
A number of different video services operate on IP networks. Applications range all the way from low-resolution, low frame rate applications such as Web cams to high-definition (HD) television and medical images. IP technology is incredibly widespread, and a huge variety of video technologies can use IP networks.
The Market for IP Video
Because so many different video applications can be implemented over IP networks, it can be hard to quantify them, and any attempt to do so will be outdated quickly. Nevertheless, a few facts and figures may be interesting:
AT&T originally rolled out its U-verseSM IPTV offering in 2004 under the code name Project Lightspeed with the intention of making it available to 19 million homes in the company's service area by the end of 2008. After planning an investment of $4.6 billion to make this a reality, they reached a million customers by the beginning of 2009.
In November 2008, China's IPTV systems reached a million viewers. China Telecom is investing 100 million yuan per year to implement the IPTV network and will set up a national IPTV business operating center to develop and innovate new products and content offerings. Of the 1 million Chinese IPTV customers, 700,000 are in Shanghai, where China Telecom plans to focus their development efforts before bringing them to other parts of the country.
By September 2006, France Telecom already had 421,000 ADSL Digital Television (IPTV) subscribers (an increase of 38% over the 306,000 IPTV subscribers reported June 30, 2006). By the end of 2008, this number had increased dramatically to 1,899,000. Figure 1.1 shows the subscriber growth over four years, with a cumulative annual growth rate of 120%.
In October, 2006, Google agreed to acquire YouTube, a leading Web site that allows users to view and upload original videos, for $1.65 billion. At the time, YouTube was delivering more than 100 million video views every day and receiving 65,000 video uploads daily. By 2008, in September alone, 12.6 billion online videos were streamed over U.S. broadband connections. Hulu.com, an Internet video portal developed and supported by NBC and Fox and launched in 2007, hosted more than 145 million of those views.
The 2008 Beijing Olympics were a global online video success story. NBC offered 2200 live hours to Internet users with 75.5 million streams served, doubling the streams offered and unique users for the 2004 Athens and 2006 Torino games combined. The 1.24 billion page views for the Beijing games were also up over 100% from the 561.1 million views for Athens and Torino combined.
Market research firm MRG predicts that the number of global IPTV subscribers will grow from 24.4 million in 2008 to 92.8 million by 2012 (with service revenue totaling over $37 billion by that time). See the Reality Check section at the end of this chapter for more detailed IPTV and broadband subscriber growth trends.
The number of applications for video transport over IP networks is large and constantly growing. This book focuses on IPTV and Internet video, which are defined in detail in Chapter 2. However, a number of other applications that use video transport over IP networks deserve to be mentioned.
Videoconferencing has moved out of the realm of dedicated rooms with specialized telecom data circuits into the world of desktop PCs interfacing with IP networks. New initiatives by HP, Cisco, and others are delivering high-performance telepresence functionality, giving users the illusion of being in the same room, whereas systems only a few years ago were characterized by low bit-rate deployments suitable for low-resolution "talking head" video but not much else.
Web cams have become widespread, particularly for low-cost, real-time communication. Applications include everything from security surveillance and business teleconferencing, to weather watching to social networking. These systems previously ran at low frame rates (10 or fewer frames per second) but now have very impressive 30 frames per second specifications that make Internet communications very effective. Most video surveillance devices intended for use in security applications have migrated to IP technology. There are a number of reasons for this transition, but one of the most compelling is the ability to use existing or easy-to-install Ethernet data cabling in place of coaxial video cables. In these networks, IP protocols and Ethernet cabling are simply used as means to provide point-to-point connectivity between cameras, video recorders, and displays.
In the world of professional video production, IP networks are used for a variety of purposes (as is the case in many other modern businesses). IP networks are used to provide connections between video editing workstations and file servers in a production studio. IP networks are used to transmit high-quality video files and live feeds from remote venues back to production facilities. They are also used to move video files containing raw footage, finished programming, and advertisements to and from virtually every studio, posthouse, and broadcaster in business today. Limelight Networks alone, for example, store over 4 petabytes of content on their network.
Not all of the aforementioned applications relate directly to the broadband focus of this book, but all of them contribute to a multibillion-dollar market momentum with IP as the video network protocol of choice.
Arguments in Favor of IP Video
There are a number of reasons companies and individuals decide to transport video signals over IP networks. Three of the most popular revolve around the flexibility of IP networks, their low cost, and the incredible coverage that IP networks provide within an organization and around the world. Let's examine each of these arguments in more detail.
Internet Protocol Network Flexibility
The number of applications of IP networks is truly staggering. One way to estimate this is to look at the number of applications that have been assigned IP port numbers managed by the Internet Assigned Numbers Authority (IANA). Among the several thousand registered ports are port 80 for the HyperText Transfer Protocol (http), port 25 for the Simple Mail Transfer Protocol (smtp), and port 110 for the Post Office Protocol–Version 3 (pop3), which are used for e-mail.
Counting the number of IP ports is just measuring the tip of the iceberg of IP applications, as many other programs use the protocols that have these port assignments. For example, there are literally dozens of e-mail programs that work on a variety of operating systems (Windows, Mac-OS, Linux, etc.), which all communicate by means of the ports defined for smtp and pop3.
Many different devices support IP. In addition to desktop and laptop PCs, servers and mainframes with a variety of different software operating systems can be configured to use IP. In addition, many other devices in the video world have Ethernet ports to enable all sorts of functions, ranging from simple status monitoring and control all the way up to HD video transport.
Internet Protocol is also very flexible because it is not tied to a specific physical communication technology. IP links have been successfully established over a wide variety of different physical links. One very popular technology for IP transport is Ethernet, which is the dominant network technology in local area networks. Many other technologies can support IP, including wireless links (such as Wi-Fi) and SONET and ATM telecom links. IP will even work across connections where several network technologies are combined, such as a wireless home access link that connects to a cable TV system offering cable modem services, which in turn sends customer data to the Internet by means of a fiber optic backbone.
For broadcasters, this flexibility is important, but it is also a challenge. It is important because it gives broadcasters a choice among a large number of technologies and business models that can be used to deliver content in new formats. It is a challenge because it is impossible to choose a single solution for delivering video over IP networks that will suit all potential viewers.
Excerpted from IPTV and Internet Video by Wes Simpson Howard Greenfield Copyright © 2009 by Elsevier Inc. . Excerpted by permission of Focal Press. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
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