One primary driver toward broadband is the increasing demand for information. Today's key competitive edge is two-fold: It includes both intellectual property (i.e., how valuable the information assets are and how smart your people are) and the ability to develop and sustain relationships well (i.e., the soft skills to maintain customer loyalty). To perform well in both of these aspects, you need an ongoing stream of the latest information with which to build your knowledge base, and you need effective communications tools to engage your customers and business associates. In an attempt to remain competitive and to grow, it is important to create an infrastructure that encourages fast and effective knowledge exchange.
Another driver toward broadband is the shifting traffic patterns we're seeing. This chapter looks at which of the traffic types are becoming dominant on the network and what they mean to the network characteristics they call on. Networks are being used more and more, and we're experiencing rapid technology advances that present us with different strategies and architectures. It becomes increasingly difficult to make a commitment to a set of technologies today because, after all, tomorrow might introduce a vastly improved architecture. With products and protocols developing so quickly, it is difficult for a given solution to become widely embraced, and without mass appeal, many products and services never have the opportunity to develop in the marketplace.
We're experiencing a wild unleashing of bandwidth, largely driven by developments in both optical networking and wireless communications. We're also seeing a trend toward advanced applications that include high degrees of visualization as well as sensory streams. Finally, convergence is driving the move to broadband, as industries, devices, and applications find natural synergies in the digital world and merge platforms with one another.
The following sections examine some of these trends in more detail and explore the ways they affect next-generation networks.
Communications Traffic Trends
For a decade, the Internet demonstrated tremendous growth rates. According to TeleGeography's 2005 survey of Internet backbone providers (www.telegeography.com), global cross-border Internet traffic grew by 49% in 2005. Although this is down from 103% in 2004, it is still phenomenal. As of early 2006, the combined average traffic on all cross-border backbone routes was 1Tbps. The average traffic is expected to range from 2Tbps to 3Tbps by 2008. The most important factor in the rate of future traffic growth is likely to be the increase in the number of broadband subscribers. However, in developed markets, the growth in broadband subscribers has begun to slow, which is a sign of market maturity.
We're also seeing a shift to machine-to-machine communications. Today there are some 6 billion people on earth, only half of whom are served by telephony services. Yet there are billions of microprocessors in existence; the increasing population of smart devices, as part of their intelligence, have communication skills and therefore also mandate some network capacity. More and more of the typical business professionals todaymany of whom work in the high-tech sector and therefore qualify as early adoptersalready have an average of at least five devices each (e.g., PCs, mobile phones, PDAs, MP3 players, pagers, smart clothing). We're looking toward a future of more and more devices communicating with one another, and someday there will be thousands of such devices for each human, not to mention an enormous array of intelligent sensors monitoring each and every move of the environment, of humans, and of animals. As discussed in this book's introduction, just about everything you can think of is having some kind of intelligence built into it in order to add value to your life. Devices are now beginning to communicate with each other more than people are communicating with each other, and this situation promises to become further exaggerated in the future.
Communications Backbone Trends
Growth and changes in traffic necessitate changes in the network backbone. Before the Internet became commercialized in 1995, backbone traffic was growing at a compound rate of about 6% to 10% per year, which was not much different from the traffic growth on the PSTN and in voice communications. But since that commercialization in 1995, traffic has been increasing at a compound annual rate of more than 100%, slowing for the first time in 2005, and as of early 2006, the average amount of traffic on the Internet's backbones was 1Tbps.
Backbone trends will be further complicated and driven by the advent of advanced applications that consume bandwidth in petabits per second (1Pbps = 1,000Tbps). Online virtual reality, for instance, would require 1Pbps to 10Pbps additional capacity on the backbone; three-dimensional holography would require 30Pbps to 70Pbps additional capacity; metacomputing, or grid computing (i.e., the harnessing of multiple computers together to compute very significant exercises such as weather prediction and warfare simulation), would require 50Pbps to 200Pbps additional capacity; and Web agents would also require an additional capacity of 50Pbps to 200Pbps. When broadband access reaches the 100Gbps rate, which is projected for later this decade, backbones will require exabits per second (1Ebps = 1 billion Gbps).
Communications Bandwidth Trends
Technology breakthroughs, particularly in optical systems, have had a profound impact on service providers, resulting in several years during which we've experienced a glut of bandwidth and sharply declining prices on intercontinental capacity. However, a study conducted by Primetrica, Inc. ("Executive Summary International Bandwidth 2005," www.telegeography.com), published in 2005, reports that prices were relatively stable in 2004: "While median prices continued to decline, these decreases were often the result of high-priced carriers bringing their rates in line with prevailing market prices, rather than by further reduction on the low end of the market." In addition, the study reports that "bandwidth demand has grown rapidly enough to offset price declines in much of the world." As a result of the current growth in bandwidth demand, additional capacity will be required. But it will not require new network construction; rather, the demand will be met by activating currently unlit wavelengths and fiber pairs, finally bringing lit supply and demand into balance.
Tremendous growth is also occurring in the wireless realm. Wireless capacity is increasing, the per-minute network costs are falling, and data is accounting for more and more of the wireless traffic. Wireless is expected to become the dominant form of Internet communication by the end of the decade. High-speed wireless communications will be the prevailing approach to Web access and between components as well. When this happens, the "anytime, anywhere" inflection point will move the e-commerce platform of choice from the desktop PC to the palmtop. Satellites are playing a bigger role every year in the broadband Internet and data access market as well.
It is also important to reflect on the role of broadband access on core network capacity requirements. Despite talk about the deployment of broadband access media in the local loop, the reality is that it still represents a relatively small percentage of the total access lines worldwide. The majority of access is still occurring via traditional analog modems. The growth in DSL, cable modems, fiber alternatives, wireless options, and even powerline communications has resulted in some 215 million users worldwide taking advantage of broadband access as of year-end 2005. But compared to the more than 1 billion or so subscriber lines that exist, even this is a relatively small percentage. Penetration levels in developed countries are quite high, but China, India, and Russia are expected to see the largest increases in broadband access in the coming years. It is important to keep in mind that adding broadband access lines puts incredible stress on the core network and will drive the demand for more bandwidth in the core. Therefore, upgrades have to occur in parallel in order to truly manifest the benefits of broadband networking end to end. (Chapter 12, "Broadband Access Alternatives," talks about all the broadband access options.)
Communications Application Trends
Much of the economic growth of the late 1990s has been attributed to productivity gains realized as a result of new communications and IT products. Workers with broadband are much more productive than workers who use dialup. Furthermore, the greater the productivity of a country, the stronger the economy. Broadband developmentwhich affects areas including home shopping, telecommuting, entertainment services, communications services, and telemedicineis viewed as a critical catalyst for the growth of the economy.
Another key trend driving the move to broadband is the changing nature of applications. A whole new generation of business-class services is stemming from e-commerce, virtual private networks (VPNs), the ability to handle voice and fax over IP, unified messaging applications, multimedia collaboration, streaming media, the ability to host content or applications, and the ability to cache content on the network edges. All these business-class communications require guaranteed performance, so before they can become fully entrenched as network services, they must provide some level of quality of service (QoS). We'll talk later in this chapter about what is needed in order for today's networks to support these types of business-class services.
We're seeing a transition from portables to wearables, such as watches with medical monitors and pagers, eyeglasses with embedded computer displays, belts and watches with embedded computers, rings with universal product code readers and displays, clothing with built-in mobile phones and MP3 players, badges that have Internet connections and tiny teleconferencing cameras, and even implants that store a person's entire medical and/or financial history. In order for this trend to really take off, we need a broadband wireless infrastructure and personal area networks (PANs) to locally connect all these smart devices. (Wireless PANs are discussed in Chapter 15, "WMANs, WLANs, and WPANs.")
We are also evolving to new industry models of information processing and communications. As we move more toward pervasive, or ubiquitous, computing, more of our sensessuch as smell and tastewill become part of what we communicate by using a network. Each person will be able to choose the media formats conducive to his or her cognitive map and then fully enjoy the realm of sight, sound, touch, smell, and even taste and touch on the network. Visualization will become three-dimensional and life-size, meaning there will be telepresence. Later this century, we will witness the enhancement and augmentation of our human powers through neural interfaces, bringing about an era, in some 25 to 30 years, whereby we'll be able to engage in virtuality without the constraint of devices that have to be worn or enclosed cubicles that have to be entered. For these models of information processing to become a reality, we need tremendous bandwidth, extremely low latencies (i.e., delays) in the network, guaranteed performance (which means administrated QoS), and broadband wireless access and PANs.
The role of broadband applications is so vital to understanding the need for broadband architectures and next-generation networks that it merits some additional discussion. Broadband applications are being developed for virtually every sector of industry, business, and government, addressing the needs and desires of both businesses and consumers.
One of the major sectors witnessing a constant stream of innovation due to broadband capabilities is the entertainment industry. Broadband introduces consumers to a range of new entertainment technologies, including high-definition video and TV over the Internet, CD-quality Internet radio, file sharing to enable exchanging of home videos and photographs, Web-based delivery of movies and large software, and sophisticated realistic online games. Already, broadband users are more likely than narrowband users to download music, listen to music online, watch video online, play games online, bank online, and trade stocks online.
Education is another sector being revolutionized by broadband networks and multimedia applications. Broadband applied to education enables interactive multimedia learning, rich-media content delivery, online testing, sophisticated learning tools, wireless campuses, and location- and income-independent education. The result is that high-quality education can be brought to those in need, including those living in rural or remote locations, developing countries, and disadvantaged communities. Research labs are working on a number of projects that will provide transformative tools for learning and research in networked environments. Among the most significant emerging technologies are visualization, advanced collaboration tools, virtual reality, telemedicine, and teleimmersion. Some of the research into these technologies has been motivated by initiatives such as Internet 2 and the Next-Generation Internet (NGI) initiative, which are facilitating fast, high-performance computing.
Broadband in health care has truly life-altering potential. The tremendous value of broadband in health care is enabling doctors to treat patients in the most remote regions; helping to reduce costs and provide better services to even the most rural and remote locations; allowing wireless networks to support online reporting and diagnostics, integrated with billing; providing emergency services; and extending regular health care to homebound patients, including doctor patient videoconferences, remote monitoring of vital signs, and remote-control use of diagnostic and surgical instruments.
Yet another key area is broadband's support of teleworking. The key teleworking applications include fast data access, enhanced communications, and videoconferencing with remote locations. Teleworking enables employees and students to work more productively from home or other remote locations. The benefits to be gained encompass reducing traffic congestion, affecting the investment needed in reengineering the transportation grid, alleviating pollution, reducing dependence on fossil fuels, improving the quality of life, and generating potentially enormous cost savings to our society.
Broadband is also vital to providing an effective national security system. Broadband contributes to national security by supporting real-time interagency coordination, monitoring, and mobilization. Because a broadband infrastructure is characterized by multiple carriers, facilities, and decentralization, it is relatively resilient and reliable in the event of disruption, and if disruptions do occur, teleworking will allow communications and work to continue from remote locations. In defense applications, broadband is vital to battlefield logistics, intelligence gathering and distribution, data tracking, and equipment maintenance.
There are endless examples of the necessity of broadband in retail, field services, transportation, mining, oil, and many other fields; the list of industries that are changing and benefiting due to broadband applications and transport is limited only by the imagination.
Part I: Communications Fundamentals
Telecommunications Technology Fundamentals
Traditional Transmission Media
Establishing Communications Channels
Part II: Data Networking and the Internet
Data Communications Basics
Local Area Networking
Wide Area Networking
The Internet and IP Infrastructures
Part III: The New Generation of Networks
Broadband Access Alternatives
Part IV: Wireless Communications
Wireless Communications Basics
WMANs, WLANs, and WPANs
Emerging Wireless Applications