Bandwidth, Physical Media, and Technologies
Two prominent trends in the current evolution of communications networks are digital technology deployment and optical fiber deployment. Most long-haul backbone communications networks have evolved from analog to digital transmission. Digital deployment in local loops to end users, however, has been proceeding slowly. However, the recent increase in the deployment of integrated services digital network (ISDN) services shows some promise for bringing the benefits of digital transmission all the way to the end user, resulting in the provision of expanded bandwidth with superior performance characteristics.
During the last decade, optical fiber capable of supporting large bandwidths (ranging from tens of megabits per second to several gigabits per second), with clear, nearly error-free transmission over long distances, has been extensively deployed in backbone communications networks that support aggregate traffic from many users. Beginning in the early 1990s, the fiber deployment has extended closer to residential neighborhoods and businesses, mostly still supporting aggregate traffic from many contiguous user locations, and in some cases
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Page 397 47 NII EvolutionTechnology Deployment Plans, Challenges, and Opportunities: AT&T Perspective Mahal Mohan AT&T Corporation Statement of the Problem This paper presents an AT&T view of the evolution of the national information infrastructure (NII). As a leading supplier of long-distance communications services and wireless services and a major force in the research and development of communications and information technologies used by customers and service providers, AT&T has a combination of perspectives on this topic that is unique in the industry. I briefly review the current state of information infrastructure in terms of certain key attributes, outline AT&T's key new technology deployment initiatives, and recommend actions by the public sector to facilitate faster, smoother evolution of the NII. Background Several attributes of emerging communications networks offer promise for supporting new modes of collaboration, information access, and exchange: • Bandwidth and the physical medium and technology used to provide the bandwidth; • The set of intelligent features that enhance the convenience or usefulness of the networking capability or service; • Messaging, involving storage, processing, and forwarding of information in different forms; • Mobility, enabling users to communicate from anywhere using wireless technologies and personal reach numbers; and • Interoperability and openness, which is an enabler for competition and rapid, ongoing innovation in each of the above areas. Bandwidth, Physical Media, and Technologies Two prominent trends in the current evolution of communications networks are digital technology deployment and optical fiber deployment. Most long-haul backbone communications networks have evolved from analog to digital transmission. Digital deployment in local loops to end users, however, has been proceeding slowly. However, the recent increase in the deployment of integrated services digital network (ISDN) services shows some promise for bringing the benefits of digital transmission all the way to the end user, resulting in the provision of expanded bandwidth with superior performance characteristics. During the last decade, optical fiber capable of supporting large bandwidths (ranging from tens of megabits per second to several gigabits per second), with clear, nearly error-free transmission over long distances, has been extensively deployed in backbone communications networks that support aggregate traffic from many users. Beginning in the early 1990s, the fiber deployment has extended closer to residential neighborhoods and businesses, mostly still supporting aggregate traffic from many contiguous user locations, and in some cases
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Page 398 supporting aggregate traffic from a single large business location. The ''last mile" that delivers information to or from individual locations has some dominant technologies today. These are twisted pair copper typically supporting symmetrical, two-way, narrow bandwidth (less than 56 kilobits per second) analog transport or, less commonly, medium bandwidth (56 kilobits per second to 1.5 megabits per second) digital transport; and coaxial cable, typically supporting broad bandwidth (the equivalent of 1.5 megabits per second or higher) analog transportmostly one-way, with two-way expansion widely planned. Intelligent Features Intelligent features constitute a broad category, and one that tends to get less than the attention it deserves in many discussions of the next generation infrastructure. A classic example of such a feature in voice (and some circuit-switched data) networks is 800 number service (and the myriad related services that have emerged in the past decade that involve database or routing-table lookup and translation in the network). The tremendous utility of such services is demonstrated by the degree of their widespread use today, mostly for voice services. In the case of data and multimedia networks such a concept again applies, albeit with different implementation details. Directory services, database services, and network-based security services are examples of intelligent service capabilities that vastly enhance the value of the underlying connectivity to users. Currently these features are offered in rudimentary form as part of data and multimedia services, often to a limited base of users. As described below, efforts by AT&T and other industry players are slated to substantially increase the deployment and use of these features beginning this year, expanding rapidly over the next several years to offer more robust and useful sets of features supporting a broader user base. Messaging Messaging, involving the storage, processing, and forwarding of information, is becoming widespread and accepted as a mode of information exchange. Voice messaging using premises-based equipment such as answering machines or computer-based voice mail systems is common now. Network-based voice messaging services are available in some areas but are less widely used; their features, functionality, and price structure need to evolve further to provide full-fledged competition to premises-based systems. Data messaging, or e-mail, is now widely used in corporations and is used by the more technically oriented consumers. Substantial progress needs to be made to provide simplified user interfaces, build user awareness, and provide user training, before e-mail can become a commonly accepted form of information exchange for a broad cross section of society. Text-to-speech conversion and vice versa are being actively worked on in research laboratories, with early implementations being used in today's commercial applications. Mobility One of the major trends in communications during the 1990s is the explosive growth of wireless services. Driven by the needs of a mobile society, greater availability of wireless spectrum, and technologies that allow increasingly more efficient and cost-effective use of the spectrum, wireless services will continue to expand rapidly. Another trend in serving mobile users is the concept of a personal number that follows users no matter where they are, if they wish to be reached. The first generation of such services has been available for a few years. The next stage in their evolution is likely to link wired and wireless access to a user via a single number.
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Page 399 Interoperability and Openness This attribute is worth singling out because it leads to competition, increased user choice, and innovation. Standard, open interfaces between local telephone networks and long-distance networks, and between information appliances and telephone company networks, have enabled substantial competition in the long-distance communications and customer premises equipment industries, even while local communications is predominantly provided in a noncompetitive environment today. Open platforms have likewise facilitated vigorous competition and innovation in many facets of the personal computer industry. As we are poised on the threshold of broader bandwidth services and an expanding range of information services, industry consensus on, and implementation of, an expanded suite of open, critical interfaces are of vital importance. Examples of interfaces that are open today are the customer premises device interface to local telephone networks, and local telephone network interfaces to long distance communications networks. Typically closed interfaces today include the cable network interface to set-top devices at homes, and the cable network interface to electronic content or programming. AT&T's Plans, Challenges, and Opportunities This section reviews some of AT&T's key new initiatives and plans in the areas of communications services and information services. It concludes with a discussion of issues that industry, users, and governments need to work together on to create a framework for rapid growth of the national information infrastructure (NII). As its corporate mission, AT&T is dedicated to being the world's best at bringing people togethergiving them easy access to each other and to the information and services they want and needanytime, anywhere. As indicated above, AT&T has multiple roles in the evolution of the NIIa major long-distance and global service provider; a major wireless service provider; a product vendor for builders of the communications infrastructure; and a provider, to consumers and businesses, of information appliances. Communications Services: Initiatives and Directions Communications services lie at the core of AT&T's business. Our worldwide intelligent network provides the bedrock on which we are building a wide variety of communications services, driven by ever more demanding user needs. Over the past decade, our worldwide network has been transformed into one that carries the vast majority of its information in digital form. Interconnecting high-capacity digital switches are high-capacity fiber-optic links that offer a combination of large bandwidth and clear, error-free transmission. To provide the highly reliable services needed by today's users, we have developed and deployed systems such as FASTAR to reroute and restore facilities handling hundreds of thousands of calls automatically, within seconds, in the event of any malfunction or failure in any portion of our network. Using the worldwide network as a basic platform, we are building families of communications services, aimed at businesses and consumers, that meet the specific needs of different user segments. These services are differentiated, each in terms of features discussed in the previous section, namely bandwidth, intelligent features, messaging capabilities, mobility, and openness and interoperability. Let us begin with a description of communications services for businesses, because many leading-edge services are first introduced to business users and, whenever appropriate, are adapted to address consumers at homes. Transport Technologies and ServicesAlternatives Using ISDN digital transport, AT&T has been offering video communications services, ranging from personal conferencing on a desktop to group conferencing with a variety of speeds and picture resolutions. The
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Page 400 most recent developments in this service family, known as AT&T WorldWorx Solutions, are global reach and multipoint capability. It is now possible to conduct video and multimedia conferences between, for example, Washington, Singapore, and Paris simultaneously, using a mix of desktop computers and group video-display systems. High-speed packet transport technologies, known as frame relay and cell relay technologies, have emerged in recent years and are spreading rapidly in use. For instance, we offer a frame relay transport service (Interspan Frame Relay Service) that connects computers at high speeds using virtual circuits that can be reconfigured as user needs change. To address user needs for simultaneous communication of voice, text, image, and video at high speeds, we have recently begun offering Interspan ATM Service, based on asynchronous transfer mode (ATM) technology, which is emerging as a worldwide industry standard for multimedia networking. A discussion of ATM from our perspective is not complete without a mention of product development initiatives. At the core of our ATM service is an ATM broadband switching product we have developed at AT&T Bell Laboratories called GlobeView-2000. GlobeView-2000 is one of a family of ATM switches under development that will enable integrated switching of multimedia signals. ATM technology is experiencing rapid growth in the field of local area networks (LANs). We believe that it has the potential to be a new unified infrastructure for communications, coexisting for decades to come with the current large embedded base of circuit-switched technology. Intelligent Features and Collaboration Tools ISDN, frame relay, and ATM services, as outlined above, offer transport alternatives that can interconnect and interwork with each other, and support high-bandwidth applications. Communications services are also growing in terms of features such as directory, security, and user interfaces. For example, this year AT&T is introducing a new family of public data services that will build on and expand the capabilities of the advanced transport services mentioned above. These will provide "multimedia dial tone" and offer a flexible applications environment for innovators. The public data services will enable companies to go beyond having sophisticated internal ("private") networks, and to connect to their suppliers and customers with data and multimedia information. AT&T NetWare Connect Services and AT&T Network Notes are part of this new family that we are beginning to beta test with selected customers and that we expect to make widely available starting later this year. We are developing AT&T NetWare Connect Services in collaboration with Novell, Inc. The service will enable high-speed LAN access and interconnection, both within an enterprise and between enterprises. It will connect to the global Internet but will offer much higher levels of security, ease of use, and directory and database capabilities. By being an open platform with standard interfaces, this service will in turn become the infrastructure for new services, of which AT&T Network Notes is an example. AT&T Network Notes, which we are developing in collaboration with Lotus Development Corporation (now part of IBM), incorporates Lotus Notes, the popular work-group collaboration software, within the AT&T network. As a result, far-flung work groups can work together on shared documents, incorporating multimedia information into them. Users can rely on the AT&T network to update the software and to readily incorporate new features. Directory services, multiple levels of user security, and navigation capabilities will be part of the common services platform and will be offered with new services as we develop themindividually or with partners in the information industry. Taken in combination with a variety of Internet services for businesses and consumers that we will be offering soon, these represent a service creation platform for a new generation of data and multimedia services. Consumer Service and Product Initiatives and Challenges The description above outlines some of the emerging communications service options for businesses to enter the multimedia networking era. What about consumers? First, businesses often tend to be early adopters of leading-edge services, and the services and technologies are subsequently adapted for use by consumers. Second,
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Page 401 many of our business communications solutions involve businesses communicating with their customers, who often happen to be consumers. For example, toll-free 800 number services are business solutions, but the people who make the 800 number calls are mostly consumers who have come to accept the services as an integral part of their daily lives. There are significant challenges in providing multimedia services to consumers on a broad scale. The most notable is the limited availability of two-way broadband access for connecting to our high-bandwidth services. As is well known, cable TV networks offer broadband connections to many homes today. What restricts their utility for most interactive multimedia services is the fact that they are currently offered as part of a closed, horizontally integrated scheme; in other words, they reach many homes, but they are generally not open to connect to everything we would want them to connect to. In addition, the access links are generally designed for one-way delivery of analog information. They also have a history of modest reliability and performance, though significant new investment is going into installing fiber optics closer to clusters of homes to aggregate coaxial cables and to provide improved performance. In our role as a major provider of telecommunications infrastructure products and capabilities, we are actively working to bridge this gap. We are working with cable companies as well as telecommunications companies to provide new solutions based on a combination of fiber-optic and coaxial cable links from homes to switching or information hubs, combining high reliability with high bandwidth for interactive applications. We are providing technology and integration capabilities that are a major part of projects by telephone companies such as Pacific Bell, Bell Atlantic, and Southern New England Telephone, as well as by cable companies such as Time Warner, to redefine their communications infrastructure and to offer reliable, broadband access to homes in the immediate future. Two other areas in communications services deployment are worthy of note. The first is the rapid growth and digitalization of wireless communications networks. AT&T Wireless, created by our acquisition of McCaw Cellular, is investing substantially in creating an equal access mechanism for wireless access to all long distance carriers; in expanding the reach of wireless services to serve major markets nationwide; and in expanding the digital capability in our wireless access network and enhancing its ability to serve more users with higher service quality. The second area is globalization. Communications companies such as ours are entering into partnerships with their counterparts in several foreign countries to offer integrated services and one-stop shopping to customers. AT&T Initiatives and DirectionsInformation Resources The two best-known types of electronic information content today are (1) electronic online services, which typically provide digitally encoded information delivered through narrowband access networks and accessed using computers, and (2) television programming, which is typically analog-coded information delivered through one-way broadband networks and accessed using TV sets. The promise of digital convergence reflects the vast potential that exists to create and store digital information and deliver it through two-way broadband access networks. AT&T is a newly emerging player in the provision of online services. Our new AT&T Interchange Online Network offers its subscribers a rich collection of online information services on a range of special-interest topics from different publishers. In addition to general news and reference services, Interchange is working closely with publishing partners, such as the Washington Post, to offer online news and information for their target customers. Interchange's graphical user environment, hypertext links, and powerful searching capabilities make it a precursor for online services that will utilize the emerging broadband access media. On another front, AT&T Bell Laboratories has developed interactive TV technologies that enable consumers to interact with the content that is delivered via their TV sets. Video server technology, developed and delivered through IDS, an AT&T partnership with Silicon Graphics, Inc. and Time Warner, Inc., is capable of storing huge quantities of multimedia information in digital form in the network for interactive uses. An important aspect of making information resources useful for people is offering users the ability to navigate among different applications, to help find and retrieve the kind of information that users need most, when
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Page 402 they need it. To this end, we have recently developed AT&T PersonaLink Service, using intelligent agent technology developed in collaboration with General Magic, Inc. The service enables users with a small handheld device to determine how specific kinds of information should be dealt withfor example, high-priority electronic mail messages from chosen persons or on chosen subjects can be automatically forwarded to a specified computer, and the user's paging device will be notified automatically to alert him or her of the message. On the other hand, lower-priority messages can be sorted and stored for future retrieval, or forwarded as needed. We are at the very beginning of intelligent agent technology, and we expect that capabilities in this area and their use will grow rapidly over time. At the nexus of information resources and communications networks is an idea that we call hosting, and this involves matching up information from a variety of content providers (information producers) with users (information consumers) no matter where they are. Key to hosting are wide reach, with wireline and wireless technology; open interfaces that interconnect multiple information resources with communications networks; and the navigation technologies referred to above, enabling users to easily sort through and obtain information they need when they need it. We are incorporating these concepts as we develop new products and services, and we intend to continue to support the principles of open, public interfaces so critical to customers and so necessary for competitive markets. We are actively participating in the Information Infrastructure Standards Panel (IISP), which is an industry group sponsored by the American National Standards Institute to identify standards gaps in today's evolving NII. Challenges and Uncertainties Access Alternatives Access technology alternatives for broad deployment deserve special attention, because they are such a fundamental enabler for many new service capabilities. Consumer applications of many of the above services will benefit immensely from the deployment of higher bandwidth access capabilities than those that exist today for supporting interactivity. The current installed base of access in telecommunications networks is predominantly twisted pair copper supporting symmetric two-way, low-speed analog transport. The current installed base for cable TV access is coaxial cable supporting high-bandwidth (hundreds of megahertz) analog transport one way (downstream only). The most straightforward extensions of telephone network access involve leaving the twisted pair copper plant in place and digitizing the transport over them. Using basic-rate ISDN, up to 144 kilobits of aggregate bandwidth can be brought to homes and businesses. ISDN technology can thus support two multiuse (voice, data, or limited-speed video) channels to the home and one or more packet data channels. These would enable access to information resources with text and graphics. Basic-rate ISDN falls short of being suitable for full-motion, large screen video applications. Local telephone companies are beginning to offer basic-rate ISDN for residential consumers, though price packages and ordering processes are complicated, and user awareness and therefore "take-rates" are limited. Another existing technology for extending the bandwidth of twisted-pair copper loops is asymmetrical digital subscriber line (ADSL). ADSL involves installing matching equipment at both ends of the customer loop that extend the bandwidth to the user substantially (typically ranging from 1.5 Mbps to 6 Mbps), while less bandwidth (typically one or two 56 kbps channels) will be available for upstream communication. ADSL's key advantage is that it can bring video services with some interactivity to users without replacing the embedded twisted-pair loop; since the installation and changes occur at the ends of the loop, ADSL devices can be disconnected from one user and moved to another user as, for example, when the first ADSL user decides to upgrade to a higher bandwidth medium such as fiber or fiber-coax access. Hybrid fiber-coaxial cable combinations are gaining in popularity for new deployment. The reasons for their popularity for new deployment are that they offer abundant bandwidth capable of supporting integrated communications and entertainment applications; are comparable in initial deployment cost to new twisted pair copper access deployment when done on a large scale; and, by offering multiple services in an integrated
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Page 403 operation, administration, and maintenance environment, can help minimize ongoing costs relative to potential service revenues. By using the combination of fiber-optic feeders and coaxial cable "drops" to user locations, the strengths of each of these media are maximized. For example, fiber provides clean, high-bandwidth transmission; but coaxial cable (unlike fiber) can be used to supply electrical power to user terminals from the communications network and is also more flexible and robust for ease of deployment. Hybrid fiber-coaxial cable combinations can be deployed in a variety of configurations supporting one-way, asymmetric two-way, and symmetric two-way services; these involve pure "bus" or "star" configurations, and combinations of the two. As a developer of a range of access technologies, we believe that broadband access systems (such as hybrid fiber-coax) can be cost-effective alternatives to twisted pair copper access for new installations. They can be deployed for about $1,000 to $1,500 per home based on a broad-scale installation. Once deployed, they enjoy the advantages of being able to support traditional telephony, traditional TV, and emerging interactive multimedia applications on a single platform with a unified operations infrastructure. The actual deployment rate will depend on the extent of competition for provision of these serviceswhich in turn will be determined by user needs and the evolution of the regulatory climate. Other Challenges Among the obstacles and challenges, we have so far focused our attention on access capabilities and their deployment. We must also point out that there is significant uncertainty relating to user demand and willingness to pay for new interactive consumer services. Experience with early deployment of services will teach industry a lot about how the emerging services should be priced, packaged, and offered to users. It is hoped that revenue from new access services will be adequate to recover the investment associated with deployment of new access network capabilities. Based on preliminary analysis, this appears to hold true for integrated access capabilities. Other uncertainties and challenges include laws and practices relating to privacy, security, liability, and intellectual property matters. An informed dialog between the public and private sector is essential to the emergence of appropriate public policy for the information age. This process has already begun, largely within the framework of the NII initiatives in industry and government. Recommendations The challenge of developing the NII industries into a number of viable market areas and addressing user needs with new products and services remains, and should continue to remain, the province of private industry. We in AT&T, along with our counterparts in industry, are actively engaged in developing new capabilities and addressing user needs. However, the public sector (at the federal and state levels) does have a key role to play in allowing these capabilities to develop toward their full potential in a speedy fashion. A major constraint on our ability to offer advanced service capabilities to consumers and small businesses is the lack of availability of full-fledged access alternatives. The public sector needs to remove today's overt and subtle impediments to the deployment and interconnection of competitive local exchange and access capabilities for consumers and businesses. The transition from the monopoly provision of local telecommunications services to an environment of multiple competing and interconnecting providers needs to be facilitated by legislators requiring the removal of constraints such as franchise restrictions, lack of interconnect points and standards, exchange resale prohibitions, lack of local number portability, and numerous other impediments. The public sector needs to work with the private sector to develop criteria and metrics to determine when a market is competitive. Regulatory efforts should be focused on opening markets to competition and doing so in a manner that inhibits the abuse of monopoly power where it exists. Hand in hand with enabling the emergence of competitive markets, the public sector needs to support industry in the development of open interfaces in critical NII locations where interoperability is necessary, and support industry-led standards for ensuring such interoperability.
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Page 404 The public sector needs to facilitate the ongoing availability of enabling resources such as wireless spectrum, numbers, and rights-of-way as new developments in the market strain limited resources. Flexibility and the ability to support market-driven solutions should in general be the guiding principles in these areas. As a major user of the NII, the public sector needs to adopt open industry standards and leverage its considerable market power as major commercial users would, to advance innovation. It should avoid creating special networks and requirements without compelling reasons, as such efforts drain resources from the mainstream development of products and services in the commercial marketplace. The public sector needs to enact laws that recognize the need for individual privacy and security of information in electronic form, and that protect intellectual property rights for information created and disseminated electronically. Although the United States can lead these efforts by example, we must recognize that these efforts are truly global in scope. Regulatory efforts should be focused on opening markets to competition and doing so in a manner that inhibits the abuse of monopoly power where it exists.
Representative terms from entire chapter: