Computer Hardware

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COMPUTER HARDWARE
Tyeps of computer system
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 supported by different
tyeps of computers.
Microcomputers system
Microcomputer are the most important category of computer systems for both businesspeople
and consumers. Consider the computing power on the Appolo 11 spacecraft. Most certainly, landing
men on the moon and returning them safely to earth was an extraordinary feat. Appolo 11 had a 2.048
MHz CPU that was built by MIIT. Today’s standards can be measured in the 4 GHz in many home.
Microcomputer come in a variety size and shapes for a variety of purposes
Corporate PC 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.
 Operating System Ready. A change in the operating system of a computer is the most disturptive
upgrade an enterprise has to face.
 Connectivity. Networked machines are a given in corporate life, and internet-ready machines are
becoming given.
 Security-Equipped. Most of the data that is processed by networked workstations in a modern
corporate environment.
Computer Terminals
Computer terminals, essentially any device that allows access to a computer, are undergoing a
major conversion to networked computer devices.
Network Computer
Network Computer (NCs) are a microcomputer category designed primarily for use with the
internet and corporate intranet
Midrange system
Midrange system are primarily high-end network servers and other tyeps of servers that can
handle the large-scale processing of many business applications.
Mainframe Computer System
Mainframe System are large, fast, and powerful computer syatem. For example, mainframes can
process thousands of million instructions per second (MIPS). The term supercomputer describes a
category of extremely powerful computer system specifically designed for scientific, engineering, and
business applications requiring extremely high speeds for massive numeric somputations.
Supercomputers use parallel processing architectures of interconnected micropocessors. Purchase
prices for large supercomputers are in the $5 million to $50 million range. The ASCI White
supercomputer system. Consists of three IBM RS/6000 SP system: White , Frost, and Ice. White, the
largest of the systems, is a 512-node, 16-way SMP supercomputer with a peak performance of 12,3
teraflops. Frost is a 68-way SMP system; and ice is a 28-node, 16-way SMP system.
Supercomputer Aid Satellite Launches
Satellite launches are a noisy affair, especially for the satellite atop the rocket. Thanks to a new
supercomputer that recently began work in japan. The Fujitsu FXI computer was inaugurated in 2009 by
the Japan Aerospace Explorations Agency (JAXA). It has 3,008 nodes, each of which has a 4-core Sparc64
VII microprocessor. Two rows of computer racks make up the main system and a third row alongside is a
second less powerful FXI machine.
Technical Note: The Computer System Concept
As a business professional, you do not need detailed technical knowledge of computers. You do
need to understand some basic concept about computer systems.
 Input. They convert data into electronic form for direct entry or through a telecommunications
network into a computer system.
 Processing. CPU is the main processing component of a computer system.
 Output. Include video display units, printers, and audio response units.
 Storage. Take place in the storage circuits of the computer’s primary storage unit, or memory.
 Control. CPU is the control component of a computer system
Moore’s Law: Where Do We Go From Here?
Gordon moore, cofounder if Intel Corporation, made his famous observation in 1967. The press
called it “Moonre’s law”, Moore observed an exponential growth in the number of transistors per
integrated circuit and predicted that this trend would continue. Moonre’s law would mean to us if it
applied beyond the number of transistors on a computer chip:
 According to moonre’s law, the estimated number of transistors shipped in 2003 was 10
 In 1978, a commercial flight between New York and Paris cost about $900 and took about seven
hours
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.
Input Technologies
Input technologies now provide a more natural user interface for computer users.
Pointing Device
Keyboards are still the most widely used devices for entering data and text into computer
system. For example, pointing devices such as an electronic mouse, trackball, and touch pads allow you
to choose easily from menu selection
Speech Recognition System
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 because speech is
the easiest, most natural means of human communication. Microsoft Office Suite 2007 has built-in
speech recognition for dictation and voice commands of a variety of software process.
Optical Scanning
Optical scanning devices read text or graphics and convert them into digital input for your
computer. You can scan documents of all kinds into your system and organize them into folders as part
of a document management library system for easy reference or retrieval. Another optical scanning
technology is called optical character recognition (OCR). Devices such as handheld optical scanning
wands are frequently used to read barcodes.
Other Input Technologies
Magnetic stripe technology is a familiar form of data entry that helps computer read credit
cards. Smart card that embed a microprocessor chip and several kilobytes of memory into debit, credit,
and other cards are popular in Europe and becoming available in the United States. Digital cameras
represent another fast-growing set of input technologies. The computer systems of the banking industry
can magnetically read checks and deposit slips using magnetic ink character recognition (MICR)
technology.
Output Technologies
Computers provide information in a variety of form. Yet other natural and attractive output
technologies such as voice response systems and multimedia output are increasingly found along with
viden displays in business applications.
Video output
Many desktop computers still on video monitors that use a catbode ray tube (CRT) technology
similar to the picture tubes used in home television sets. The biggest use of liquid crystal display (LCDs)
has been to provide a visual display capability for portable microcomputers and PDAs.
Printed output
Computers can produce printed reports and correspondence, documents such as sales invoices,
payroll checks, bank statements, and printed versions of graphic display. Inkjet printers, which spray ink
onto a page. Laser print use an electrostatics process similar to a photocopying machine.
Storage trade-offs
Progress in very-large-scale integration (VLSI), which packs millions of memory circuit elements
on tiny semiconductor memory chips, is responsible for continuing increases in the main-memory
capacity of computers.
Computer Storage Fundamental
Data are processed and stored in a computer system through the presence or absence
electronic or magnetic signals in the computer’s circuitry or in the media it users.
Direct and sequential Access
Primary storage media such as semiconductor memory chips are called direct access memory or
random-access memory (RAM), magnetic disk devices are frequently called direct access storage device
(DASDs).
Semiconductor Memory
The primary storage of your computer consist of microelectronic semiconductor memory chips.
Examples include external cache memory of 512 kilobytes to help your microprocessor work faster or a
video graphics accelerator card with 64 megabytes or more of RAM for faster and clearer video
performance.
 RAM, random-access memory, these memory chips are the most widely used primary storage
medium.
 ROM, read-only memory, nonvolatile random-access memory chips used for permanent storage
Magnetic Disk
Magnetic disk are the most common from the secondary storage for your computer system.
Type of Magnetic Disk
There are several types of magnetic dis arragment
 Floppy disk, or magnetic disketters, consist of polyester film disk covered with an iron
oxide compound. The 3½-inch floppy disk, with capacities of 1.44 megabytes, was the
most widely used version, with a superdisk technology offering 120 megabytes of
storage.
 Hard disk drives combine magnetic disk, access arms, and read/write heads into a sealed
module.
Magnetic Tape
Magnetic tape is still being used as a secondary storage medium in business application. Include
tape reels and cartridges in mainframes and midrange systems and small cassettes or cartridges for PCs.
Can hold more than 200 megabytes.
Optical disk
CD-ROM technology uses 12-centimeter. Each disk can store more than 600 megabytes. CD-R is
another popular optical disk technology. DVD-ROM disks are increasingly replacing magnetic tape video
cassettes for movie and other multimedia products.
Business applications
One of the major uses of optical disks in mainframe and midrange systems is in image
processing, where long-term archival storage of historical files of document image must be maintained.
Radio frequency identification
Radio frequency identification (RFID), a system for tagging and identifying mobile objects such
as store merchandise, postal packages, and sometimes aven living organisms (like pets). The RFID
technology works using small pieces of hardware called RFID chips.
RFID privacy issues
The use of RFID technology has caused considerable controversy and even product boycotts by
consumer privacy advocates who prefer to RFID tags as spychips. The potential for privacy violation with
RFID was demonstrated by its use in a pilot program by the gillette company. The controversy
surrounding the use of RFID technologies was furthered by the accidental exposure of a proposed Auto-
ID.
Predictions for the future
If moore’s law prevails and technology advancement continues, we can expected to see our lives
change in remarkable and unimaginable ways.


TELECOMMUNICATIONS AND NETWORKS
The Networked Enterprise
Telecommunications and network technologies are internetworking and revolutionizing
business and society
The Concept of a Network
The concept of networks can be expressed as a mathematical formula that calculates the
number of possible connections or interactions in a one-way communication environment
Metcalfe’s Law
Metcalfe’s law states that the usefulness, or utility, of a network equals the square of the
number of users.
Metcalfe’s law become easy to understand if you think of common piece of technology we all
use every day: the telephone.
Trends in telecommunication
Telecommunications is the exchange of information in any form over network
 Industry trend: toward more competitive vendors, carriers, alliances, and network services,
accelerated by deregulation and the growth of the internet and the World Wide Web.
 Technology trend: toward extensive use of internet, digital fiber-optic, and wireless technologies
to create high-speed local and global internetworks, data, images, audio, and
videocommunication
 Application trend: toward the persive use of the internet, enterprise intranets, and
interorganizational extranets to support electronic business and commerce, enterprise
collaboration, and strategic advantage in local and global market.
 Internet2: internet2 is a high-performance network that uses an entirely different infrastructure
than the public internet we know today. The internet2 network may never become totally open;
it might remain solely in the domain of universities, research centers, and government. Most of
institutions and commercial partners on the internet2 network are connected via Abilene, a
network backbone that will soon support troughtput of 10 gigabits per second (Gbps).
The internet revolution
The internet has become the largest and most important network of networks today and has
evolved into a global information superbigbway. When this netwok of networks began to grow in
December 1991, it had about 10 server. In January 2004, the internet was estimated to have more than
46 million connected servers. In January 2007, the internet was estimated to have more than 1 billion
users.
Internet service provide
An ISP, or internet service provide, is a company that provides access to the internet to
individuals and organizations.
Internet Application
The internet provides electronic discussion forums and bulletin board systems formed and
managed by thousands of special-internet newsgroups.
The business value of the internet
Web sites to achieve six major business values:
 Generate new revenue from onlie sales.
 Reduce transaction costs through online sales and customer support.
 Attract new cuntomers via web marketing and advertising and online sales.
 Increase the loyalty of existing customers via improved web customer service and
support.
 Develop new web-based markets and distribution channels for existing products.
 Develop new information-based products accessible on the web.
The business value of intranets
 Communications and collaboration. Intranets can significantly improve communications and
collaboration within an enterprise.
 Web publishing. The advantage of developing and publishing hyperlinked multimedia
documents to hypermedia database accessible on World Wide web severs has moved to
corporate intranets.
 Business operation and management. Intranets have moved beyond merely making hypermedia
information available on Web servers or pushing it to users via net broadcasting.
 Intranet portal management. Organizations must employ IT and IS professionals to manage the
functions of the intranet along with maintaining the various hardware and software components
necessary for successful operations.
The role of extranets
Extranets are network links that use internet technologies to interconnect the internet of a
business with the intranets of its consumers, suppliers, or other business partner. Companies can
establish direct private network links among themselves or create private, secure internet links called
virtual private networks (VPNs).
Telecommunications network alternative
Telecommunications is a highly technical, rapidly chagging field of information systems
technology.
A telecommunications network model
Which shows that it five basic categories of components:
 Terminals, such has networked personal computers, network computers, or information
appliances.
 Telecommunications processors, which support data transmission and reception
between terminals and computers.
 Telecommunications channel, over which data are transmitted and received.
 Computers of all size and types are interconnected by telecommunications networks so
that can carry out their information processing assignments.
 Telecommunications control software, consist of programs that control
telecommunications activities and manage the functions of telecommunications
networks.
Types of telecommunications networks
 Wide area networks
Telecommunications networks covering a large geographic area are called wide area network
(WANs). Networks that cover a large city or metropolitan area (metropolitan area networks)
 Metropolitan area networks (MAN)
Such networks can range from several blocks of buildings to entire cities.
 Local area networks (LANs)
Connect computers and other information processing devices within a limited physical area,
such as an office, classroom, building, manufacturing plant, or other worksite
 Virtual Private networks (VPNs)
A virtual private network is a secure network that uses the internet as its main backbone
network but relies on network firewalls, encryption, and other security features of its internet
and intranet connection and those of participating organizations
Clients/server networks
In a client/server networks, end-users PC or NC workstations are the clients. They are
interconnected by local area network and share application processing with network servers, which also
manage the networks. A continuing trend is the downsizing of large computer system by replacing them
with client/server networks.
Peer-to-peer network
The emergence of peer-to-peer (P2P) networking technologies and applications for the internet
is being hailed as a development that will have a major impact on e-business and e-commerce and the
internet itself. The peer-to-peer network architecture has no central directory or server. The internet,
as originally conceived in the late 1960’s was a peer-to-peer system the goal of original ARPANET was to
share computing resource around the United States.
Digitala and analog signal
Analog and digital refer to the method used to convert information into an electrical signal. In
an analog system, an electrical voltage or current is generated that is proportional to the quantity baing
observed. In the case of an electronic digital thermometer, however, the output would be the number
83 if the temperature were 83 degrees.
Wired technologies
 Twisted-pair wire
Twisted-pair wiring is wrapped or shielded in a variety of forms and used extensively in home
and office telephone systems and many local area networks and wide area networks.
 Coaxial cable
Coaxial cable consist of a sturdy copper or aluminum were wrapped with spacers to insulate and
protect it and are used instead of twisted-pair wire lines in high-service metropolitan areas, are
also used in many office buildings and other worksite for local area networks.
 Fiber optics
Fiber optics uses cables consisting of one or more hair-thin filaments of glass fiber wrapped in a
protective jacket. Fiber-optic cables are not affected by and do not generate electromagnetic
radiaction
The problem of “The Last Mile”
Difined as worldwide Interoperability for Microwave Access. WiMax is intended to provide high-
speed, mobile telecommunications services to diverse Internet connection and location.
Wireless Technologies
Wireless telecommunications technologies rely on radio wave, microwave, infrared to transport
digital communications without wires between communications device.
 Terrestrial microwave involves earthbound microwave system that transmit high-speed radio
signal in a line-of-sight path between relay stations spaced approximately 30 miles apart.
 Communications satellites also use microwave radio as their telecommunications medium.
 Cellular and PCS telephone and pager system use several radio communications technologies.
Cellular phone system have long used analog communications technologies operating at
frequencies in the 800-900MHz cellular band.
 Wireless LAN: the use wireless LANs is growing rapidly as new high-speed technologies are
implemented.
 Bluetooth: a short-rang wireless technology called Bluetooth is rapidly baing built into
computers and other devices. Bluetooth serves as a cable-free wireless connection to peripheral
devices such as computer printers and scanners.
 The wireless web: wireless access to the internet, intranet, and extranet is growing as more web
enabled information appliances proliferate. Communications devices have become very thin
client in wireless networks.
Telecommunications processors
Such as modem, multiplexers, switches, and routers perform a variety of support functions
between the computers and other devices in a telecommunications network.
 Modem, are the most common type of communications processor. They convert the digital
signals from the computer or transmission terminal at one end of the communications link into
analog frequencies that can be transmitted over ordinary telephone line.
 Internet processors, telecommunications networks are interconnected by special-purpose
communications processors called internetwork processor, such as switches, routers, hubs, and
gateways.
 Multiplexers is a communications processor that allows a single communications channel to
carry simultaneous data transmission from many terminals.
Telecommunications software
Is a vital component of all telecommunications networks. Telecommunications fuctions built
into Microsoft windows and other operating systems provide a variety of communications support
services.
 Network management, example of major network management function include the following:
 Traffic management
 Security
 Network monitoring
 Capacity planning
Networks architecture and protocols
Telecommunication manufacturers and national and international organizations have developed
standards called network architecture to support the development of advanced data communications
networks.
 Protocols: a protocols is standard set of rules and procedures for the control of communications
in a network.
 The OSI model: the open system interconnection (OSI) model is standard description or
“reference model” for hoe message should be transmitted between ant two points in a
telecommunication network. Message destined for some other host are not passed to the upper
layers but are forwarded to other host. The seven layer are:
 Layer 1: the physical layer
 Layer 2: the data link layer
 Layer 3: the network layer
 Layer 4: the transport layer
 Layer 5: the session layer
 Layer 6: the presentation layer
 Layer 7: the application layer
 The internet’s TCP/IP: the internet users a system of telecommunications protocols that has
become so widely used that it is now accepted as a network architecture. The internet’s
protocol suite is called transmission control protocol/internet protocol and is known as TCP/IP.
The current IP addressing protocol is called IPv4. IP addressing can identify a specific network
connected to the internet. IP address space should be divided into three address classes-classes
A,B, and C. class A networks are defined by the first number in an IP address. Class B network
addresses range from 128.0 to 255.254. class C addresses range from 192.0 to 233.255.255 and
represent 12.5 percent of the available IPv4 address space.
 Voice over IP: this approach makes use of a packet-based (or switched) network to carry voice
calls, instead of the traditional circuit-switched-network. Skype users can call to any non-
computer-based landline or mobile telephone in the world and call other skype users for free.
Bandwidth alternatives
The communications speed and capacity of telecommunications networks can be classified by
bandwidth. Bandwidth represents the capacity of the connection. Narrow-band channels typically
provide low speed transmission rates up to 64Kbps but can now handle up to 2Mbps. Broadband
channels provide high-speed transmission rates at intervals from 256Kbps to several billion bps.
Switching alternative
Packet switching involves subdividing communications messages into fixed or variable-leght
groups called packets. Frame relay is another popular packet switching protocol and is used by many
large companies for their wide area networks.
Networks interoperability
Section 256 of the communications Act, enacted in February 1996, states two key purposes: (1)
“to promote nondiscriminatory accessibility”, and (2) “to ensure the ability of users and information”. As
you can see, the FCC is a key regulatory agency with regard to telecommunications. The answer lies in
the importance of a concept called network interoperability. This interoperability ensures that anyone
anywhere on one network can communicate with anyone anywhere on another network without having
worry about speaking a common language from a telecommunications perspective. Fortunately for us,
they work together to ensure that all networks remain interoperable.

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