Lectura Capitulo 3. Sistemas de Información Gerencial, James O´Brien
Management ChallengesMODULE II Business Applications Module II Information Technologies Development Foundation Processes ConceptsINFORMATIONTECHNOLOGIES W hat challenges do information system technologies pose for busi- ness professionals? What basic knowledge should you possess about information technology? The four chapters of this module give you an overview of the hardware, software, and data resource management and telecommunications network technologies used in information systems and their implications for business managers and professionals. • Chapter 3: Computer Hardware reviews history, trends, and developments in microcomputer, midrange, and mainframe computer systems; basic computer system concepts; and the major types of technologies used in peripheral devices for computer input, output, and storage. • Chapter 4: Computer Software reviews the basic features and trends in the major types of application software and system software used to support enter- prise and end user computing. • Chapter 5: Data Resource Management emphasizes management of the data resources of computer-using organizations. This chapter reviews key database management concepts and applications in business information systems. • Chapter 6: Telecommunications and Networks presents an overview of the Internet and other telecommunications networks, business applications, and trends, and reviews technical telecommunications alternatives.68
Management ChallengesCHAPTER 3 Business Applications Module II Information Technologies Development Foundation Processes ConceptsCOMPUTER HARDWAREChapter Highlights Learning ObjectivesSection I After reading and studying this chapter, you should beComputer Systems: End User and Enterprise able to:Computing 1. Understand the history and evolution of com-Real World Case: Mobile Devices and Wireless puter hardware.Technologies Are a Must-Have: Return on Investment IsNo Longer a Concern 2. Identify the major types and uses of microcom-Introduction puter, midrange, and mainframe computerA Brief History of Computer Hardware systems.Types of Computer Systems 3. Outline the major technologies and uses of com-Microcomputer Systems puter peripherals for input, output, and storage.Midrange Systems 4. Identify and give examples of the components andMainframe Computer Systems functions of a computer system.Technical Note: The Computer System Concept 5. Identify the computer systems and peripheralsMoore’s Law: Where Do We Go from Here? you would acquire or recommend for a businessSection II of your choice, and explain the reasons for yourComputer Peripherals: Input, Output, and selections.Storage TechnologiesReal World Case: Delta, Northwest Airlines, andVancouver Airport: The Business Value of CustomerSelf-Service KiosksPeripheralsInput TechnologiesOutput TechnologiesStorage Trade-OffsSemiconductor MemoryMagnetic DisksMagnetic TapeOptical DisksRadio Frequency IdentificationReal World Case: Verizon Communications, AAA, andOthers: Advances in Speech Recognition Software AreExtending the Utility of Traditional Applications 69
70 ● Module II / Information Technologies SECTION I Computer Systems: End User and Enterprise ComputingIntroduction All computers are systems of input, processing, output, storage, and control compo- nents. In this section, we will discuss the history, trends, applications, and some basic concepts of the many types of computer systems in use today. In Section II we will cover the changing technologies for input, output, and storage that are provided by the peripheral devices that are part of modern computer systems. Read the Real World Case on making the business case for mobile computing sys- tems. We can learn a lot about how businesses use mobile computing devices from this case. See Figure 3.1.A Brief History Today we are witnessing rapid technological changes on a broad scale. However, many centuries elapsed before technology was sufficiently advanced to develop computers.of Computer Without computers, many technological achievements of the past would not haveHardware been possible. To fully appreciate their contribution, however, we must understand their history and evolution. While a thorough discussion of computing history is be- yond the scope of this text, a brief look at the development of the computer is possible. Let’s look briefly into the development of computers. At the dawn of the human concept of numbers, humans used their fingers and toes to perform basic mathematical activities. Then our ancestors realized that by using some objects to represent digits, they could perform computations beyond the limited scope of their own fingers and toes. Shells, chicken bones, or any number of objects could have been used, but the fact that the word calculate is derived from calculus, the Latin word for small stone, suggests that pebbles or beads were arranged to form the familiar abacus, arguably the first human-made computing device. By manipulating the beads, it is possible with some skill and practice to make rapid calculations. Blaise Pascal, a French mathematician, invented what is believed to be the first me- chanical adding machine in 1642. The machine adopted partly the principles of the abacus, but did away with the use of the hand to move the beads or counters. Instead, Pascal used wheels to move counters. The principle of Pascal’s machine is still being used today, such as in the counters of tape recorders and odometers. In 1674, Gottfried Wilhelm Von Leibnitz improved Pascal’s machine so that the machine could divide and multiply as easily as it could add and subtract. When the age of industrialization spread throughout Europe, machines became fixtures in agricultural and production sites. An invention that made profound changes in the history of industrialization, and in the history of computing, was the mechani- cal loom invented by a Frenchman named Joseph Jacquard. With the use of cards punched with holes, it was possible for the Jacquard loom to weave fabrics in a variety of patterns. The idea of using punched cards to store a predetermined pattern to be woven by the loom clicked in the mind of Charles Babbage, an English mathematician who lived in the 19th century. He foresaw a machine that could perform all mathematical calculations, store values in its memory, and perform logical comparisons among values. He called it the Analytical Engine. Babbage’s analytical engine, however, was never built. It lacked one thing—electronics. Herman Hollerith eventually adopted the punched card concept of Jacquard to record census data in the late 1880s. Census data were translated into a series of holes in a punched card to represent the digits and the letters of the alphabet. The card was then passed through a machine with a series of electrical contacts that were either turned off or on depending on the existence of holes in the punched cards. These differ- ent combinations of off/on situations were recorded by the machine and represented a
Chapter 3 / Computer Hardware ● 71 1REAL WORLD Mobile Devices and Wireless Technologies Are a Must-Have: Return CASE on Investment Is No Longer a ConcernI t is usually the case that chief information officers (CIOs) need to be concerned with the return on investment (ROI) associated with the decision to deploy a particulartechnology solution. When it comes to wireless technolo-gies used to empower a mobile workforce, the ROI seems to keyboard, and a battery life unrivaled among hand-held wireless devices all contribute to BlackBerry’s popularity. Scott Griffin, CIO at The Boeing Co. in Chicago, said his company also uses BlackBerry devices extensively with seemingly little regard to cost. Boeing does not do an ROIbe a minor issue. Such technologies have become so in- on mobility, he noted. “Some people simply must be con-grained in companies that return-on-investment concerns nected, and then we figure out how much mobility theyare often deemed less important than total connectivity of need.”the workforce. Griffin said that because Boeing seems to move each of For example, Northrop Grumman Corp. CIO Keith its workers to new locations on an annual basis, buildingGlennan said the aerospace company views Research in wireless connections into company facilities makes sense. It’sMotion Ltd.’s BlackBerry hand-held systems as essential to easier and less expensive to hook up transplanted employeesits global operations. At a CIO forum sponsored by the Wire- via wireless links than by installing new Ethernet jacks, heless Internet for the Mobile Enterprise Consortium at the said.University of California, Los Angeles, Glennan said that the But Griffin added that IT managers also have to thinkLos Angeles-based company has rolled out 5,500 BlackBerry through how to deliver all of Boeing’s applications so theyunits to its employees, making it one of the largest users of can be used on small LCD screens. That includes the appli-the wireless devices. cations now used by Boeing’s engineers on high-end scien- In fact, every time Research in Motion releases a new tific workstations. The major challenge with this requirementmodel, Northrop Grumman tests the technology in a corpo- lies in the fact that to fully port an application to a smallerrate jet to ensure that it can provide mobile services to screen, a large portion of the application’s interface must beexecutives while they’re in transit. Cost isn’t the issue— re-created. Often, this can be more costly than the originalconnectivity is. application. The BlackBerry appears to be the current product of Companies all over the world are moving to large-scalechoice for wireless devices, and a review of its capabilities wireless solutions for their employees. Lance Perry, vicereveals why. BlackBerry wireless devices provide users with president of IT infrastructure at Cisco Systems Inc., said thephone, e-mail, text messaging, Web browser, and organizer networking vendor has about 30,000 remote users in 100applications in a compact and intuitive handheld. Features countries. “Even 9-to-5 workers have mobility needs whenthat most attract corporate users include the large, high- they go home,” he pointed out.resolution screen and 65,000ϩ color display. In addition, Corporate IT executives can’t afford to ignore or dismissintegrated e-mail attachment viewing, the brightly backlit mobility requirements because of ROI concerns, Perry ad- vised. Mobile computing capabilities have become “a criticalFIGURE 3.1 component of a company’s success,” he said. But Perry added that companies can better manage their costs by using wireless technology to its fullest. For example, they could give end users IP-based “soft phones” built into PCs for use in making international calls over public-access wireless networks. Long a popular gadget for lawyers and businesspeople, the BlackBerry wireless hand-held device has even been drafted into the U.S. war on terrorism. Massachusetts State Police officers patrolling Boston’s Logan International Airport are using BlackBerry devices to perform background checks on suspicious individuals, ac- cording to LocatePlus Holdings Corp., which makes the AnyWhere RIM BlackBerry product used by police for the checks. State police checking up on suspicious persons and vehi- cles in the field can compare information at the scene to Modern businesses depend on mobile computing devices to give them a competitive edge in LocatePlus’s Internet database, which contains information a fast-paced, competitive environment. on more than 200 million U.S. residents, according to a statement attributed to Massachusetts State Police Lt. Thomas Coffey.Source: Chris Hondros/Getty Images.
Chapter 3 / Computer Hardware ● 73 way of tabulating the result of the census. Hollerith’s machine was highly successful. It cut by two-thirds the time it took to tabulate the result of the census, and it made money for the company that manufactured Hollerith’s machine. In 1911 this company merged with its competitor to form International Business Machines (IBM). The ENIAC (Electronic Numerical Integrator and Computer) was the first elec- tronic digital computer. It was completed in 1946 at the Moore School of Electrical Engineering of the University of Pennsylvania. ENIAC had no moving parts. It was programmable and had the capability to store problem calculations. ENIAC used vacuum tubes (about 18,000). A computer that uses vacuum tube technology is called a first-generation com- puter. The ENIAC could add in 0.2 of a millisecond or about 5,000 computations per second. The principal drawback of ENIAC was its size and processing ability. It occu- pied over 1,500 square feet of floor space and could process only one program or prob- lem at a time. Figure 3.2 shows the ENIAC complex. In the 1950s, Remington Rand manufactured the UNIVAC I (Universal Automatic Calculator). It could calculate at the rate of 10,000 additions per second. In 1957, IBM developed the IBM 704, which could perform 100,000 calculations per second. In the late 1950s, transistors were invented and quickly replaced the thousands of vacuum tubes used in electronic computers. A transistor-based computer could per- form 200,000 to 250,000 calculations per second. The transistorized computer repre- sents the second generation of computer. It was not until the mid-1960s that the third generation of computers came into being. These were characterized by solid state technology and integrated circuitry coupled with extreme miniaturization. In 1971 the fourth generation of computers was characterized by further miniatur- ization of circuits, increased multiprogramming, and virtual storage memory. In the 1980s the fifth generation of computers operated at speeds of 3 to 5 million calcula- tions per second (for small-scale computers) and 10 to 15 million instructions per second (for large-scale computers). The age of microcomputers began in 1975 when a company called MITS intro- duced the ALTAIR 8800. The computer was programmed by flicking switches on the front. It came as a kit and had to be soldered together. It had no software programs. But it was a personal computer available to the consumer for a few thousand dollars when most computer companies were charging tens of thousand of dollars. In 1977 both Commodore and Radio Shack announced that they were going to make personal computers. They did, and trotting along right beside them were Steve Jobs and Steve Wozniak, who invented their computer in a garage while in college. Mass productionFIGURE 3.2ENIAC was the first digitalcomputer. It is easy to seehow far we have come inthe evolution of computers. Source:
74 ● Module II / Information Technologies of the APPLE began in 1979, and by the end of 1981, it was the fastest selling of all the personal computers. In August 1982 the IBM PC was born, and many would argue that the world changed forever as a result. Following the introduction of the personal computer in the early 1980s, we used our knowledge of computer networks gained in the early days of computing and com- bined it with new and innovative technologies to create massive networks of people, computers, and data where anyone can find almost anything: the Internet. Today we continue to see amazing advancements in computing technologies. Okay, it’s time to slow down a bit and begin our discussion on today’s computer hardware.Types of Today’s computer systems come in a variety of sizes, shapes, and computing capa- bilities. Rapid hardware and software developments and changing end user needsComputer continue to drive the emergence of new models of computers, from the smallest hand-Systems held personal digital assistant/cell phone combinations to the largest multiple-CPU mainframe for the enterprise. See Figure 3.3. Categories such as mainframe, midrange, and microcomputer systems are still used to help us express the relative processing power and number of end users that can be sup- ported by different types of computers. But these are not precise classifications, and they do overlap each other. Thus, other names are commonly given to highlight the major uses of particular types of computers. Examples include personal computers, network servers, network computers, and technical workstations. In addition, experts continue to predict the merging or disappearance of several computer categories. They feel, for example, that many midrange and mainframe systems have been made obsolete by the power and versatility of networks composed of microcomputers and servers. Other industry experts have predicted that the emer- gence of network computers and information appliances for applications on the Internet and corporate intranets will replace many personal computers, especially in large organizations and in the home computer market. Only time will tell whether such predictions will equal the expectations of industry forecasters.FIGURE 3.3 Examples of computer system categories. Microcomputer Systems Personal computers, network computers, technical workstations, personal digital assistants, information appliances, etc. Midrange Systems Network servers, minicomputers, Web servers, multiuser systems, etc. Mainframe Systems Enter prise systems, superservers, transaction processors, supercomputers, etc.
Chapter 3 / Computer Hardware ● 75Microcomputer The entire center of gravity in computing has shifted. For millions of consumers and business users, the main function of desktop PCs is as a window to the Internet. Com-Systems puters are now communications devices, and consumers want them to be as cheap as possible . Microcomputers are the most important category of computer systems for both businesspeople and consumers. Though usually called a personal computer, or PC, a mi- crocomputer is much more than a small computer for use by an individual. The com- puting power of microcomputers now exceeds that of the mainframes of previous computer generations, at a fraction of their cost. Thus, they have become powerful networked professional workstations for business professionals. Microcomputers come in a variety of sizes and shapes for a variety of purposes, as Figure 3.4 illustrates. For example, PCs are available as hand-held, notebook, laptop, tablet, portable, desktop, and floor-standing models. Or, based on their use, they in- clude home, personal, professional, workstation, and multiuser systems. Most micro- computers are desktops designed to fit on an office desk, or laptops for those who want a small, portable PC. Figure 3.5 offers advice on some of the key features you should consider in acquiring a high-end professional workstation, multimedia PC, orFIGURE 3.4 Examples of microcomputer systems. a. A notebook microcomputer. b. The microcomputer as a professionalworkstation. c. The microcomputer as a technical workstation.Source: Courtesy of Hewlett-Packard. Source: Corbis. Source: Courtesy of Hewlett-Packard.
76 ● Module II / Information TechnologiesFIGURE 3.5 Examples of recommended features for the three types of PC users. Note: www.dell.com andwww.gateway.com are good sources for the latest PC features available. Business Pro Multimedia Heavy Newcomer To track your products, customers, and Media pros and dedicated amateurs Save money with a Celeron performance, you’ll need more than just will want at least a Mac G4 or a processor in the 1–2GHz a fast machine: 2–3GHz Intel chip, and: range. Also look for: • 2–3 Gigahertz processor • 512MB RAM • 256MB RAM • 512MB RAM • 120GB hard drive or more • 40GB hard drive • 80GB hard drive • 18-inch or larger CRT, flat-panel • Internal 56K modem LCD, or plasma display • 18-inch flat-panel display • CD–RW/DVD drive • CD–RW/DVD drive or portable hard • High-end color printer • 17-inch CRT or 15-inch drives for backup • CD–RW/DVDϩRW drive flat panel LCD • Network interface card (NIC) • Deluxe speaker system • Basic inkjet printer beginner’s system. This should give you some idea of the range of features available in today’s microcomputers. Some microcomputers are powerful workstation computers (technical worksta- tions) that support applications with heavy mathematical computing and graphics dis- play demands such as computer-aided design (CAD) in engineering, or investment and portfolio analysis in the securities industry. Other microcomputers are used as network servers. They are usually more powerful microcomputers that coordinate telecommu- nications and resource sharing in small local area networks (LANs) and in Internet and intranet websites. Corporate PC What do you look for in a new PC system? A big, bright screen? Zippy new proces- Criteria sor? Capacious hard drive? Acres of RAM? Sorry, none of these is a top concern for corporate PC buyers. Numerous studies have shown that the price of a new com- puter is only a small part of the total cost of ownership (TCO). Support, mainte- nance, and other intangibles contribute far more heavily to the sum. Let’s take a look at three top criteria. Solid Performance at a Reasonable Price. Corporate buyers know that their users probably aren’t mapping the human genome or plotting trajectories to Saturn. They’re doing word processing, order entry, sales contact management, and other essential business tasks. They need a solid, competent machine at a reasonable price, not the latest whizbang. Operating System Ready. A change in the operating system of a computer is the most disruptive upgrade an enterprise has to face. That’s why many corporate buy- ers want their machines to be able to handle current operating systems and antici- pated new ones. While some enterprises still use Windows 9x or NT, they must be able to make a possible transition to Windows XP soon, and even to OS versions expected three to five years out. Primarily, that means deciding what hard disk space and RAM will be sufficient. Connectivity. Networked machines are a given in corporate life, and Internet- ready machines are becoming a given. Buyers need machines equipped with reliable
Chapter 3 / Computer Hardware ● 77 network interface cards or even wireless capabilities. With fewer cables to worry about, wireless networks, especially when combined with laptop PCs, contribute to the flexibility of the workplace and the simplicity of PC deployment. Many organi- zations are planning for Internet-based applications and need machines ready to make fast, reliable, and secure connections.Computer Terminals Computer terminals, essentially any device that allows access to the computer, are un- dergoing a major conversion to networked computer devices. Dumb terminals, which are keyboard/video monitor devices with limited processing capabilities, are being re- placed by intelligent terminals, which are modified networked PCs or network comput- ers. Also included are network terminals, which may be Windows terminals that are dependent on network servers for Windows software, processing power, and storage, or Internet terminals, which depend on Internet or intranet website servers for their operating systems and application software. Intelligent terminals take many forms and can perform data entry and some infor- mation processing tasks independently. This includes the widespread use of transac- tion terminals in banks, retail stores, factories, and other work sites. Examples are automated teller machines (ATMs), factory production recorders, and retail point-of- sale (POS) terminals. These intelligent terminals use keypads, touch screens, bar code scanners, and other input methods to capture data and interact with end users during a transaction, while relying on servers or other computers in the network for further transaction processing.Network Computers Network computers (NCs) are a microcomputer category designed primarily for use with the Internet and corporate intranets by clerical workers, operational employees, and knowledge workers with specialized or limited computing applications. NCs are low-cost, sealed microcomputers with no or minimal disk storage that are linked to the network. Users of NCs depend primarily on network servers for their operating sys- tem and Web browser, application software, and data access and storage. One of the main attractions of network computers is their lower TCO (total cost of ownership; that is, the total of all costs associated with purchasing, in- stalling, operating, and maintaining a computer). Purchase upgrades, maintenance, and support cost much less than for full-featured PCs. Other benefits to business include ease of software distribution and licensing, computing platform standard- ization, reduced end user support requirements, and improved manageability through centralized management and enterprisewide control of computer network resources . See Figure 3.6.Information PCs aren’t the only option: A host of smart gadgets and information appliances—fromAppliances cellular phones and pagers to hand-held PCs and Web-based game machines—promise Internet access and the ability to perform basic computational chores . Hand-held microcomputer devices known as personal digital assistants (PDAs) are some of the most popular devices in the information appliance category. Web- enabled PDAs use touch screens, pen-based handwriting recognition, or keypads so that mobile workers can send and receive e-mail, access the Web, and exchange infor- mation such as appointments, to-do lists, and sales contacts with their desktop PCs or Web servers. One of the latest entrants to PDA technology is the RIM BlackBerry, a small pager-sized device that can perform all of the common PDA functions, plus act as a fully functional mobile telephone. What sets this device apart from other wireless
78 ● Module II / Information TechnologiesFIGURE 3.6An example of a networkcomputer. Source: Courtesy of Sun Microsystems Inc. PDA solutions is that it is always on and connected. A BlackBerry user doesn’t need to retrieve e-mail—the e-mail finds the BlackBerry user. Because of this functional- ity, there is no need to dial in or to initiate a connection. The BlackBerry doesn’t even have a visible antenna. When a user wishes to send or reply to an e-mail, the small keyboard on the device allows text entry. Just like a mobile telephone, the BlackBerry is designed to remain on and continuously connected to the wireless network, allowing near real-time transfer of e-mail. Further, since the BlackBerry uses the same network as most mobile telephone services, the unit can be used anywhere that a mobile phone can be used. Information appliances may also take the form of video-game consoles and other devices that connect to your home TV set. These devices enable you to surf the World Wide Web or send and receive e-mail and watch TV programs or play video games at the same time. Other information appliances include wireless PDAs and Internet- enabled cellular and PCS phones, and wired telephone-based home appliances that can send and receive e-mail and access the Web.Midrange Midrange systems are primarily high-end network servers and other types of servers that can handle the large-scale processing of many business applications. Though notSystems as powerful as mainframe computers, they are less costly to buy, operate, and maintain than mainframe systems, and thus meet the computing needs of many organizations. See Figure 3.7. Burgeoning data warehouses and related applications such as data mining and online analytical processing are forcing IT shops into higher and higher levels of server configu- rations. Similarly, Internet-based applications, such as Web servers and electronic commerce, are forcing IT managers to push the envelope of processing speed and storage capacity and other [business] applications, fueling the growth of high-end servers . Midrange systems have become popular as powerful network servers (computers used to coordinate communications and manage resource sharing in network settings) to help manage large Internet websites, corporate intranets and extranets, and other networks. Internet functions and other applications are popular high-end server
Chapter 3 / Computer Hardware ● 79FIGURE 3.7Midrange computer systemscan handle large-scaleprocessing without the highcost or space considerationsof a large-scale mainframe. Source: David Zalubowski/AP Photo/Wide World. applications, as are integrated enterprisewide manufacturing, distribution, and finan- cial applications. Other applications, like data warehouse management, data mining, and online analytical processing (which we discuss in Chapters 5 and 9), are con- tributing to the demand for high-end server systems . Midrange systems first became popular as minicomputers for scientific research, instrumentation systems, engineering analysis, and industrial process monitoring and control. Minicomputers could easily handle such uses because these applications are narrow in scope and do not demand the processing versatility of mainframe sys- tems. Today, midrange systems include servers used in industrial process-control and manufacturing plants, and play a major role in computer-aided manufacturing (CAM). They can also take the form of powerful technical workstations for computer-aided design (CAD) and other computation-intensive and graphics-intensive applications. Midrange systems are also used as front-end servers to assist mainframe computers in telecommunications processing and network management. Los Alamos Los Alamos National Laboratory and Washington-based e-learning software and Laboratory and application service provider (ASP) Blackboard Inc. (www.blackboard.com) are finding that blade servers cost 30 to 50 percent less than traditional rack-mounted Others: Moving servers, with the biggest savings derived from their smaller size, low power- to Blade Servers consumption costs, and the reduced costs of cabling, power supply management, and integrated telecom switching. A blade server is a thin, modular electronic circuit board. It contains one, two, or more microprocessors and memory, and is intended for a single, dedicated appli- cation (such as serving Web pages). It can be easily inserted into a space-saving rack with many similar servers. One product offering, for example, makes it possible to install up to 280 blade server modules vertically in multiple racks or rows of a single floor-standing cabinet. Blade servers are designed to create less heat and thus save
80 ● Module II / Information Technologies energy costs as well as space. Large data centers and Internet service providers (ISPs) that host Web sites are among companies most likely to buy blade servers. Dollar Rent A Car Inc. (www.dollar.com) began using HP blade servers in 2002 to help speed the deployment of new Web and data center applications while keep- ing costs down, and expanded their use in 2003. Meanwhile, AOL (www.aol.com) began testing IBM BladeCenter servers running in 2002 as part of their goal of reducing IT costs by 30 percent in 2003. Freed of the physical bulk and componentry of traditional servers, blade servers slide into slots on racks. In most cases, blade servers consist of microcomputer pro- cessing and storage assemblies that fit into slots in a rack unit that provides a common cooling fan, cabling, and network and external storage connections, reducing both ca- bling and space requirements. Analysts say cost savings increase the longer these sys- tems are used. “Blade servers take up less space, generate less heat, use less power, and don’t need the environment requirements of air conditioning or raised flooring, as larger servers require,” says Tom Manter, research director at Aberdeen Group. The primary caveat in trying to achieve quick returns on investment for blade servers largely rests on how well the processing, networking, and storage features are inte- grated. “Any cost savings can quickly be eaten away if maintaining blade servers be- comes complex and time-consuming,” says John Humphreys, an analyst at IDC .Mainframe Several years after dire pronouncements that the mainframe was dead, quite the opposite is true: Mainframe usage is actually on the rise. And it’s not just a short-term blip. OneComputer factor that’s been driving mainframe sales is cost reductions [of 35 percent or more]. PriceSystems reductions aren’t the only factor fueling mainframe acquisitions. IS organizations are teaching the old dog new tricks by putting mainframes at the center stage of emerging applications such as data mining and warehousing, decision support, and a variety of Internet-based applications, most notably electronic commerce . Mainframe systems are large, fast, and powerful computer systems. For example, mainframes can process thousands of million instructions per second (MIPS). Main- frames can also have large primary storage capacities. Their main memory capacity can range from hundreds of gigabytes to many terabytes of primary storage. Mainframes have slimmed down drastically in the last few years, dramatically reducing their air- conditioning needs, electrical power consumption, and floor space requirements, and thus their acquisition and operating costs. Most of these improvements are the result of a move from cumbersome water-cooled mainframes to a newer air-cooled technology for mainframe systems . See Figure 3.8. Thus, mainframe computers continue to handle the information processing needs of major corporations and government agencies with high transaction pro- cessing volumes or complex computational problems. For example, major interna- tional banks, airlines, oil companies, and other large corporations process millions of sales transactions and customer inquiries each day with the help of large main- frame systems. Mainframes are still used for computation-intensive applications such as analyzing seismic data from oil field explorations or simulating flight conditions in designing aircraft. Mainframes are also widely used as superservers for the large client /server networks and high-volume Internet websites of large com- panies. And as previously mentioned, mainframes are becoming a popular business computing platform for data mining and warehousing, and electronic commerce applications .Supercomputer Supercomputers have now become “scalable servers” at the top end of the product linesSystems that start with desktop workstations. Market-driven companies, like Silicon Graphics, Hewlett-Packard, and IBM, have a much broader focus than just building the world’s
Chapter 3 / Computer Hardware ● 81FIGURE 3.8Mainframe computersystems are the heavy liftersof corporate computing. Source: Corbis. fastest computer, and the software of the desktop computer has a much greater overlap with that of the supercomputer than it used to, because both are built from the same cache-based microprocessors . The term supercomputer describes a category of extremely powerful computer systems specifically designed for scientific, engineering, and business applications requiring extremely high speeds for massive numeric computations. The market for supercomputers includes government research agencies, large universities, and major corporations. They use supercomputers for applications such as global weather fore- casting, military defense systems, computational cosmology and astronomy, micro- processor research and design, large-scale data mining, and so on. Supercomputers use parallel processing architectures of interconnected micro- processors (which can execute many instructions at the same time in parallel). They can easily perform arithmetic calculations at speeds of billions of floating-point operations per second (gigaflops). Supercomputers that can calculate in teraflops (tril- lions of floating-point operations per second), which use massively parallel processing (MPP) designs of thousands of microprocessors, are now in use. Purchase prices for large supercomputers are in the $5 million to $50 million range. However, the use of symmetric multiprocessing (SMP) and distributed shared mem- ory (DSM) designs of smaller numbers of interconnected microprocessors has spawned a breed of minisupercomputers with prices that start in the hundreds of thousands of dol- lars. For example IBM’s RS/6000 SP starts at $150,000 for a one-processing-node SMP computer. However, it can be expanded to hundreds of processing nodes, which drives its price into the tens of millions of dollars. The ASCI White supercomputer system, shown in Figure 3.9, consists of three IBM RS/6000 SP systems: White, Frost, and Ice. White, the largest of these systems, is a 512-node, 16-way symmetric multiprocessor (SMP) supercomputer with a peak performance of 12.3 teraflops. Frost is a 68-node, 16-way SMP system, and Ice is a 28-node, 16-way SMP system . Supercomputers like these continue to advance the state of the art for the entire computer industry.
82 ● Module II / Information TechnologiesFIGURE 3.9The ASCI Whitesupercomputer systemat Lawrence LivermoreNational Laboratory inLivermore, California. Source: Courtesy of IBM.Technical As a business professional, you do not need a detailed technical knowledge of com- puters. However, you do need to understand some basic concepts about computerNote: The systems. This should help you be an informed and productive user of computer sys-Computer tem resources.System A computer is more than a high-powered collection of electronic devices perform- ing a variety of information processing chores. A computer is a system, an interrelatedConcept combination of components that performs the basic system functions of input, processing, output, storage, and control, thus providing end users with a powerful information processing tool. Understanding the computer as a computer system is vital to the effective use and management of computers. You should be able to visualize any computer this way, from the smallest microcomputer device, to a large computer network whose components are interconnected by telecommunications network links throughout a building complex or geographic area. Figure 3.10 illustrates that a computer is a system of hardware devices organized according to the following system functions: • Input. The input devices of a computer system include computer keyboards, touch screens, pens, electronic mice, optical scanners, and so on. They convert data into electronic form for direct entry or through a telecommunications network into a computer system. • Processing. The central processing unit (CPU) is the main processing compo- nent of a computer system. (In microcomputers, it is the main microprocessor. See Figure 3.11.) Conceptually, the circuitry of a CPU can be subdivided into two major subunits: the arithmetic-logic unit and the control unit. It is the elec- tronic circuits (known as registers) of the arithmetic-logic unit that perform the arithmetic and logic functions required to execute software instructions. • Output. The output devices of a computer system include video display units, printers, audio response units, and so on. They convert electronic information produced by the computer system into human-intelligible form for presentation to end users. • Storage. The storage function of a computer system takes place in the storage circuits of the computer’s primary storage unit, or memory, supported by
Chapter 3 / Computer Hardware ● 83FIGURE 3.10 The computer system concept. A computer is a system of hardware components and functions. Central Processing Unit Control Unit Arithmetic-Logic Unit Interprets Instructions Performs Arithmetic Input Devices and Directs Processing Operations and Makes Output Devices Enter Data and Comparisons Communicate Instructions System Bus and Record into the CPU Information Primary Special Storage (Memory) Cache Purpose Stores Data and Memory Processors Program Instructions during Processing Keyboard Visual Display Unit Mouse Printer Touch Screen Audio-Response Optical Scanner Physical Control Voice Recognition Secondary Devices etc. Storage etc. Devices Store Data Magnetic Disk and and Programs Tape Units, Optical for Processing Disks, etc. secondary storage devices such as magnetic disk and optical disk drives. These devices store data and software instructions needed for processing. Computer processors may also include storage circuitry called cache memory for high-speed, temporary storage of instruction and data elements. • Control. The control unit of a CPU is the control component of a computer system. Its registers and other circuits interpret software instructions and transmit directions that control the activities of the other components of the computer system.FIGURE 3.11This Intel Mobile Pentium4-M microprocessoroperates at 3GHz clockspeeds to bring desktoppower to laptop PCs. Source: Courtesy of Intel Corp.
84 ● Module II / Information Technologies We will explore the various hardware devices associated with each of these system functions in the next section of this chapter.Computer How fast are computer systems? Early computer processing speeds were measuredProcessing Speeds in milliseconds (thousandths of a second) and microseconds (millionths of a second). Now computers operate in the nanosecond (billionth of a second) range, with picosecond (trillionth of a second) speed being attained by some computers. Such speeds seem almost incomprehensible. For example, an average person taking one step each nanosecond would circle the earth about 20 times in one second! We have already mentioned the teraflop speeds of some supercomputers. However, most computers can now process program instructions at million instructions per sec- ond (MIPS) speeds. Another measure of processing speed is megahertz (MHz), or mil- lions of cycles per second, and gigahertz (GHz), or billions of cycles per second. This rating is commonly called the clock speed of a microprocessor, since it is used to rate mi- croprocessors by the speed of their timing circuits or internal clock rather than by the number of specific instructions they can process in one second. However, such ratings can be misleading indicators of the effective processing speed of microprocessors and their throughput, or ability to perform useful computa- tion or data processing assignments during a given period. That’s because processing speed depends on a variety of factors including the size of circuitry paths, or buses, that interconnect microprocessor components; the capacity of instruction processing regis- ters; the use of high-speed cache memory; and the use of specialized microprocessors such as a math coprocessor to do arithmetic calculations faster.Moore’s Law: Can computers get any faster? Can we afford the computers of the future? Both of these questions can be answered by understanding Moore’s law. Gordon Moore, co-Where Do We founder of Intel Corp., made his famous observation in 1965, just four years after theGo from Here? first integrated circuit was commercialized. The press called it “Moore’s law” and the name has stuck. In its form, Moore observed an exponential growth (doubling every 18 to 24 months) in the number of transistors per integrated circuit and predicted that this trend would continue. Through a number of advances in technology, Moore’s law, the doubling of transistors every couple of years, has been maintained, and still holds true today. Figure 3.12 illustrates Moore’s law as it relates to the evolution of computing power.FIGURE 3.12 TransistorsMoore’s law suggests Moore’s Law Intel® Itanium® 2 Processor 1,000,000,000that computer power will Intel® Itanium® Processordouble every 18 to 24months. So far, it has. 100,000,000 Intel® Pentium® 4 Processor Intel® Pentium® III Processor Intel® Pentium® II Processor 10,000,000 Intel® Pentium® Processor Intel486TM Processor 1,000,000 Intel386TM Processor 286 100,000 8086 10,000 8080 8008 4004 1,000 1970 1975 1980 1985 1990 1995 2000 2005
Chapter 3 / Computer Hardware ● 85 Over the years, Moore’s law has been interpreted and reinterpreted such that it iscommonly defined in a much broader sense than it was originally offered. Nonethe-less, its application, and its relative accuracy, is useful in understanding where we havebeen and in predicting where we are going. For example, one common corollary ofMoore’s law is that the price of a given level of computing power will be cut in halfapproximately every 18 to 24 months. While Moore didn’t predict this effect specifi-cally, it has been shown to be fairly consistently accurate as well. This is also true forthe cost of storage (we will explore this further in the next section). Although Moore’s law was initially made in the form of an observation and predic-tion, the more widely it became accepted, the more it served as a goal for an entireindustry—driving both marketing and engineering departments within semiconductormanufacturers to focus enormous energy aiming for the specified increase in process-ing power that it was presumed one or more of their competitors would soon actuallyattain. Expressed as “a doubling every 18 to 24 months,” Moore’s law suggests thephenomenal progress of technology in recent years. Expressed on a shorter timescale,however, Moore’s law equates to an average performance improvement in the industryas a whole of over 1 percent a week. For a manufacturer competing in the processor,storage, or memory markets, a new product that is expected to take three years todevelop and is just two or three months late is 10 to 15 percent slower or larger thanthe directly competing products, thus rendering it harder to sell. Recent computer industry studies predict that Moore’s law will continue to holdfor the next several chip generations (at least another decade). Depending on the dou-bling time used in the calculations, this could mean up to a 100-fold increase in tran-sistor counts on a chip in the next 10 years. This rapid exponential improvement couldput 100GHz personal computers in every home and 20GHz devices in every pocket.It seems reasonable to expect that sooner or later computers will meet or exceed anyconceivable need for computation. Regardless of what the end of Moore’s law maylook like, or when it may arrive, we are still moving along at a phenomenal rate of evo-lution, and the best may be yet to come. CTION II
86 ● Module II / Information Technologies SECTION II Computer Peripherals: Input, Output, and Storage Technologies The right peripherals can make all the difference in your computing experience. A top- quality monitor will be easier on your eyes—and may change the way you work. A scanner can edge you closer to that ever-elusive goal—the paperless office. Backup-storage systems can offer bank-vault security against losing your work. CD and DVD drives have become essen- tial for many applications. Thus, the right choice of peripherals can make a big difference . Read the Real World Case on self-service kiosks in the airline industry. We can learn a lot about the business value of consolidating computer operations and systems from this case. See Figure 3.13.Peripherals Peripherals is the generic name given to all input, output, and secondary storage devices that are part of a computer system, but are not part of the CPU. Peripherals depend on direct connections or telecommunications links to the central processing unit of a computer system. Thus, all peripherals are online devices; that is, they are separate from, but can be electronically connected to and controlled by, a CPU. (This is the opposite of offline devices that are separate from and not under the control of the CPU.) The major types of peripherals and media that can be part of a computer system are discussed in this section. See Figure 3.14.Input Input technologies now provide a more natural user interface for computer users. You can enter data and commands directly and easily into a computer system throughTechnologies pointing devices like electronic mice and touchpads, and with technologies like optical scanning, handwriting recognition, and voice recognition. These developments have made it unnecessary to always record data on paper source documents (such as sales order forms, for example) and then to keyboard the data into a computer in an additional data-entry step. Further improvements in voice recognition and other technologies should enable an even more natural user interface in the future.Pointing Devices Keyboards are still the most widely used devices for entering data and text into com- puter systems. However, pointing devices are a better alternative for issuing commands, making choices, and responding to prompts displayed on your video screen. They work with your operating system’s graphical user interface (GUI), which presents you with icons, menus, windows, buttons, bars, and so on, for your selection. For example, pointing devices such as an electronic mouse, trackball, and touchpads allow you to easily choose from menu selections and icon displays using point-and-click or point- and-drag methods. See Figure 3.15. The electronic mouse is the most popular pointing device used to move the cur- sor on the screen, as well as to issue commands and make icon and menu selections. By moving the mouse on a desktop or pad, you can move the cursor onto an icon dis- played on the screen. Pressing buttons on the mouse initiates various activities repre- sented by the icon selected. The trackball, pointing stick, and touchpad are other pointing devices most often used in place of the mouse. A trackball is a stationary device related to the mouse. You turn a roller ball with only its top exposed outside its case to move the cursor on the screen. A pointing stick (also called a trackpoint) is a small button-like device, some- times likened to the eraser head of a pencil. It is usually centered one row above the space bar of a keyboard. The cursor moves in the direction of the pressure you place
Delta, Northwest Airlines, 2REAL WORLD and Vancouver Airport: The Business Value of Customer CASE Self-Service KiosksF or travelers, the best trips are fast and hassle-free, with limited time spent at the airport. That’s why Atlanta- based Delta Air Lines Inc. (www.delta.com) teamed upwith its technology subsidiary, Delta Technology Inc., todeploy hundreds of self-service check-in kiosks at airports of 2004. “On May 1, 2004 our Minneapolis/St. Paul hub achieved a record 74 percent of check-in transactions per- formed through one of our convenient self-service check-in options,” said Al Lenza, vice president of e-commerce and distribution. “With the rapid growth we are experiencing, byacross the country, with a goal of speeding travelers to their the end of the year we expect that at least 70 percent of ourdestinations. customers, system-wide, will be choosing nwa.com online Mike Childress, senior vice president of development at check-in or an e-Service Center kiosk for their check-inDelta Technology and the project’s leader, says there are needs,” said Lanza.now 449 kiosks installed at airports in 81 U.S. cities. The Rob Maruster, Delta Air Lines’ director of airport strat-kiosks had been part of Delta’s multiyear business plan, egy and service, says the kiosks help customers shave 5 tobut when airports increased security in the wake of the 15 minutes off the time they have to stand in line. PassengersSeptember 11 terrorist attacks—and the amount of time can use the kiosks to check in for their flights, get boardingcustomers spent waiting in line grew longer—the airline passes for originating or connecting flights, select or changedecided to accelerate the project. Delta acknowledges that seats, request to stand by for an upgrade, check baggage,it had been trailing some other carriers’ kiosk initiatives be- change flights, and initiate multiparty check-ins.fore September 11. Delta added more than 400 kiosks in late 2004 and en- For example, Northwest Airlines (www.nwa.com) had hanced functionality to include international check-in and feeembraced self-service airport kiosks in a big way before collection. With this change, Delta will offer customers moreDelta. Northwest had over 650 e-Service Center check-in than 800 kiosks in airports nationwide. “From the businesskiosks in over 150 airports, more than any other airline, and side, the kiosks are the cornerstone of a broader airport strat-added over 100 more kiosks at the end of 2003. In fact, more egy to offer customers more control,” Maruster says.of Northwest’s customers are using self-service check-ins Since the project was launched in November 2001, theby checking in online on the Web at nwa.com, or through airline has spent $5 million to $7 million on customer-one of their e-Service Center check-in kiosks, than through service initiatives, including the kiosks, he says. Marustertraditional check-in methods. says the payback has been enormous, but he declines to give Thus, more than half of eligible customers now choose financial details. Delta says it is on track to check in 13 millionone of Northwest’s self-service check-in options, a record high. to 14 million people in 2005.At the carrier’s Detroit World Gateway and Minneapolis/ Delta Technology purchased the self-service check-inSt. Paul airport hubs, usage has averaged 70 percent. Sys- kiosks from Kinetics USA (www.kineticsusa.com), the domi-temwide usage has continued to soar through the end nant supplier of self-service kiosks in the airline industry, with six of the top ten airlines in the world using KineticsFIGURE 3.13 self-service technology. The self-service kiosks are really net- worked special-purpose microcomputer terminals, featuring video touch screens as the primary user interface, a built-in high-speed thermal printer for printing flight itineraries and boarding passes, and a magnetic-stripe card reader to read customers’ airline and credit cards. Childress says an internal application-development team integrated the kiosk functionality with Delta’s Digital Nervous System, the network that communicates with every part of the Delta organization. “In 2002, we de- ployed over 300 kiosks in 81 cities,” Childress says. “From start to finish, it took six months, and we were checking in half a million people per month. We wouldn’t have been able to do it without the infrastructure.” Childress says he learned how important it is to have the application and business teams work together. “Having a team that knows what they want to achieve from a strategy and business Self-service check-in kiosks make checking in both quick and easy while creating increased efficiency perspective enables the technology team to drive a solution and lower costs for airlines. as soon as possible.” Vancouver International Airport has taken the airline kiosk idea to a whole new level. The Vancouver AirportSource: Tim Boyle/Newsmakers/Getty Images. 87
88 ● Module II / Information TechnologiesAuthority deployed 80 new “common-use” kiosks that support second-busiest airport, with more than 15 million passengersall airline customer check-in requirements, thus eliminating and 274,400 takeoffs and landings last year.the need for kiosks dedicated to just one airline. But there’s also a more practical nature to using the com- The new system, developed by IBM and Arinc Inc., an mon-access kiosk to support Vancouver’s 22 airlines, saidAnnapolis, Maryland-based communications and engineer- Molloy. “If each airline were to bring in their own kiosk,ing firm, is based on a new industry software standard called they may actually turn into obstacles to processing passen-“CUSS,” or common-use self-service. Passengers can access gers,” he said.many different airlines’ self-service check-in applications Recently, the airport authority also installed some of thefrom a single kiosk. Air Canada was the first airline to use the new kiosks in its parking areas and at curbside valet parkingkiosks for its Express Check-in. Since their installation, how- locations, allowing passengers to check in before enteringever, over half of the airlines flying in and out of Vancouver the airport’s terminals. In addition, the Vancouver Airport’sare using the system. kiosks will eventually be installed in locations such as hotel Kevin Molloy, vice president of IT for the airport au- lobbies and cruise ship terminals.thority, said the cost savings are “massive.” For example, The economic benefits of the common-access kiosksa study conducted by his office in 2000 revealed that to makes that level of deployment possible, said Molloy.continue supporting the airport’s projected passenger load “There’s no way to place 22 kiosks in a hotel lobby,” he said.would require an additional 145 check-in counters at a costof $1 million each. That cost would eventually be recouped Source: Adapted from Linda Rosencrance, “Self-Service Check-In Kiosksfrom the airlines, he said. Give Travelers More Control,” Computerworld, February 24, 2003, p. 48; Kinetics Inc., “Touch Your World,” www.kinetics.tv, August 25, 2003; and Vancouver International is the second-largest interna- Dan Vertin, “Vancouver Deploys First Common-Use Kiosk for Airlinetional passenger gateway on the West Coast and Canada’s Check in,” Computerworld, October 10, 2002. CASE STUDY QUESTIONS REAL WORLD ACTIVITIES 1. What computer system technologies and functions are 1. Self-service kiosks are certainly helping the airline included in self-service kiosks? What other technolo- industry. Using the Internet, see if you can find other gies should be provided? Why? Visit the Kinetics USA industries that are benefiting from the use of kiosks. website for more details. 2. Given the plans to deploy kiosks into areas such as 2. What is the customer value of self-service kiosks for parking lots and hotel lobbies, what do you see as the airline check-ins? What other services should be pro- next step in kiosk use? Break into small groups with vided? Take the demo tour of the Delta check-in kiosk your classmates and discuss the future of self-service at www.delta.com/travel/trav_serv/kiosk to help you kiosks. Do you think there are downsides to their use? answer. 3. What is the business value of self-service kiosks in the airline industry? Do self-service kiosks give airlines a competitive advantage? Why or why not?
Chapter 3 / Computer Hardware ● 89FIGURE 3.14 Peripherals ChecklistSome advice aboutperipherals for a • Monitors. Bigger is better for computer screens. Consider a high-definition 19-inch orbusiness PC. 21-inch flat screen CRT monitor, or LCD flat panel display. That gives you much more room to display spreadsheets, Web pages, lines of text, open windows, etc. An increasingly popular setup uses two monitors that allow multiple applications to be used simultaneously. • Printers. Your choice is between laser printers or color inkjet printers. Lasers are bet- ter suited for high-volume business use. Moderately priced color inkjets provide high- quality images and are well suited for reproducing photographs. Per-page costs are higher than for laser printers. • Scanners. You’ll have to decide between a compact, sheet-fed scanner or a flatbed model. Sheet-fed scanners will save desktop space, while bulkier flatbed models provide higher speed and resolution. • Hard Disk Drives. Bigger is better; as with closet space, you can always use the extra capacity. So go for 40 gigabytes at the minimum to 80 gigabytes and more. • CD and DVD Drives. CD and DVD drives are a necessity for software installation and multimedia applications. Common today is a built-in CD-RW/DVD drive that both reads and writes CDs and plays DVDs. • Backup Systems. Essential. Don’t compute without them. Removable mag disk drives and even CD-RW and DVD-RW drives are convenient and versatile for backing up your hard drive’s contents. on the stick. The touchpad is a small rectangular touch-sensitive surface usually placed below the keyboard. The cursor moves in the direction your finger moves on the pad. Trackballs, pointing sticks, and touchpads are easier to use than a mouse for portable computer users and are thus built into most notebook computer keyboards. Touch screens are devices that allow you to use a computer by touching the sur- face of its video display screen. Some touch screens emit a grid of infrared beams, sound waves, or a slight electric current that is broken when the screen is touched. The computer senses the point in the grid where the break occurs and responds with an ap- propriate action. For example, you can indicate your selection on a menu display by just touching the screen next to that menu item.Pen-Based Handwriting-recognition systems convert script into text quickly and are friendly toComputing shaky hands as well as those of block-printing draftsmen. The pen is more powerful than the keyboard in many vertical markets, as evidenced by the popularity of pen-based devices in the utilities, service, and medical trades .FIGURE 3.15 Many choices exist for pointing devices including the trackball, mouse, pointing stick, and touch screen.Source: Courtesy of Source: Courtesy of IBM.Logitech. Source: Don Wright/AP Photos/Wide World. Source: Courtesy of Microsoft.
90 ● Module II / Information TechnologiesFIGURE 3.16Many PDAs acceptpen-based input. Source: RNT Productions/Corbis. Pen-based computing technologies are being used in many hand-held computers and personal digital assistants. Tablet PCs and PDAs contain fast processors and software that recognizes and digitizes handwriting, handprinting, and hand drawing. They have a pressure-sensitive layer, similar to that of a touch screen, under their slate-like liquid crystal display (LCD) screen. Instead of writing on a paper form fas- tened to a clipboard or using a keyboard device, you can use a pen to make selections, send e-mail, and enter handwritten data directly into a computer. See Figure 3.16. Various pen-like devices are available. One example is the digitizer pen and graphics tablet. You can use the digitizer pen as a pointing device, or use it to draw or write on the pressure-sensitive surface of the graphics tablet. Your handwriting or drawing is digitized by the computer, accepted as input, displayed on its video screen, and entered into your application.Speech Recognition Speech recognition is gaining popularity in the corporate world among nontypists, peopleSystems with disabilities, and business travelers, and is most frequently used for dictation, screen navigation, and Web browsing . Speech recognition may be the future of data entry and certainly promises to be the easiest method for word processing, application navigation, and conversational computing, since speech is the easiest, most natural means of human communication. Speech input has now become technologically and economically feasible for a variety of applications. Early speech recognition products used discrete speech recognition, where you had to pause between each spoken word. New continuous speech recognition (CSR) software recognizes continuous, conversationally paced speech. See Figure 3.17. Speech recognition systems digitize, analyze, and classify your speech and its sound patterns. The software compares your speech patterns to a database of sound patterns in its vocabulary and passes recognized words to your application software. Typically, speech recognition systems require training the computer to recognize your voice and its unique sound patterns in order to achieve a high degree of accuracy. Training such systems involves repeating a variety of words and phrases in a training session, as well as using the system extensively. Continuous speech recognition software products like Dragon NaturallySpeaking and ViaVoice by IBM have up to 300,000-word vocabularies. Training to 95 percent