Principles of Information Systems Eighth Edition

1
Principles of Information SystemsEighth Edition

• Chapter 7
• The Internet, Intranets, and Extranets

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Why Learn About the Internet?

• Internet is an important part of most peoples
  lives
• Individuals can investigate career opportunities
• Businesses sell and advertise online
• Employees can communicate with coworkers and
  bosses

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Use and Functioning of the Internet

• Internet a collection of interconnected
  networks, all freely exchanging information
• ARPANET
• Ancestor of the Internet
• Project started by the U.S. Department of Defense
  (DoD) in 1969

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Use and Functioning of the Internet (continued)

• Internet Protocol (IP) communication standard
  that enables traffic to be routed from one
  network to another as needed
• Research to make Internet faster and easier to
  use
• Digital objects allow all types of computer
  systems to use and share programs and data
• Internet2 (I2), Next Generation Internet (NGI),
  Abilene provide Internet speeds of up to 2 Gbps
  or more

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Use and Functioning of the Internet (continued)
Table 7.1 A Brief History of the Internet
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How the Internet Works

• Internet transmits data from one computer (called
  a host) to another
• If the receiving computer is on a network to
  which the first computer is directly connected,
  it can send the message directly
• If the receiving computer is not on a network to
  which the sending computer is connected, the
  sending computer relays the message to another
  computer that can forward it

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How the Internet Works (continued)

• Data is passed in chunks called packets
• Transmission Control Protocol (TCP) widely used
  transport layer protocol that is used in
  combination with IP by most Internet applications
• Uniform Resource Locator (URL) assigned address
  on the Internet for each computer

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How the Internet Works (continued)

• Accessing the Internet
• Connect via LAN server
• Connect via Serial Line Internet Protocol
  (SLIP)/Point-to-Point Protocol (PPP)
• Connect via an online service
• Other ways to connect cell phones, PDAs, and home
  appliances e.g., wireless application protocol
  (WAP) for cell phones

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How the Internet Works (continued)
Figure 7.1 Routing Messages over the Internet
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How the Internet Works (continued)
Table 7.2 U.S. Top-Level Domain Affiliations
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How the Internet Works (continued)
Figure 7.2 Internet Growth Number of Internet
Domain Names
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How the Internet Works (continued)
Figure 7.3 Several Ways to Access the Internet
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Internet Service Providers

• Internet service provider (ISP) any company that
  provides individuals or organizations with access
  to the Internet
• Most charge a monthly fee
• Many ISPs and online services offer broadband
  Internet access through digital subscriber lines
  (DSLs), cable, or satellite transmission

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The World Wide Web

• Also called the Web, WWW, or W3
• Menu-based system that uses the client/server
  model
• Organizes Internet resources throughout the world
  into a series of menu pages, or screens, that
  appear on your computer
• Hypermedia tools that connect the data on Web
  pages, allowing users to access topics in
  whatever order they wish

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The World Wide Web (continued)

• Hypertext Markup Language (HTML) standard page
  description language for Web pages
• HTML tags let the browser know how to format
  text on a Web page and whether images, sound, and
  other elements should be inserted
• Extensible Markup Language (XML) markup language
  for Web documents containing structured
  information, including words, pictures, and other
  elements

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The World Wide Web (continued)
Figure 7.4 Sample Hypertext Markup Language
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Web Browsers

• Web browser software that creates a unique,
  hypermedia-based menu on a computer screen,
  providing a graphical interface to the Web
• Menu consists of graphics, titles, and text with
  hypertext links
• Popular Web browsers Microsoft Internet
  Explorer, Netscape Navigator, Mozilla Firefox,
  Apple Computers Safari
• Applet small program embedded in Web pages
• Web browser plug-in external program that is
  executed by a Web browser when it is needed

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Search Engines and Web Research

• Search engine Web search tool
• Examples Yahoo.com, Google.com
• Most search engines are free
• Searches can use words, such as AND and OR to
  refine the search
• Meta-search engine submits keywords to several
  individual search engines and returns results
  from all these search engines

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Search Engines and Web Research (continued)
Table 7.6 Popular Search Engines
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Web Programming Languages

• Java
• Object-oriented programming language from Sun
  Microsystems based on C
• Allows small programs (applets) to be embedded
  within an HTML document

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Web Programming Languages (continued)
Figure 7.6 Downloading an Applet from a Web
Server
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Web Programming Languages (continued)

• Other programming languages used to develop Web
  sites
• JavaScript
• VBScript
• ActiveX
• Hypertext Preprocessor (PHP)

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Developing Web Content

• Suggestions for creating a Web page
• Computer must be linked to a Web server
• Web browser program needed to view the HTML pages
  you create
• Options for designing the Web page
• Write your copy with a word processor, and use an
  HTML converter to convert the page into HTML
  format
• Use an HTML editor to write text and add HTML
  tags
• Edit an existing HTML template to meet your needs
  
• Use an ordinary text editor and type the start
  and end tags for each item

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Developing Web Content (continued)

• Suggestions for creating a Web page (continued)
• See HTML page in browser correct any mistakes
• Add links to your home page
• Store pictures as files before adding them
• Draw them using a graphics software package
• Copy pictures from other Web pages (with
  permission)
• Buy a disk of clip art
• Scan photos
• Use a digital camera

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Developing Web Content (continued)

• Suggestions for creating a Web page (continued)
• Add sound by using a microphone connected to your
  computer to create a file, and then adding a link
  to the file on a Web page
• Upload the HTML file to your Web site
• Review the Web page to make sure that all links
  are correctly established to other Web sites
• Advertise your Web page to others and encourage
  them to take a look and send feedback by e-mail

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Web Services

• Web services standards and tools that streamline
  and simplify communication among Web sites for
  business and personal purposes
• XML is used within a Web page to describe and
  transfer data between Web service applications

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Internet and Web Applications

• The types of Internet and Web applications
  available are vast and ever expanding

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Business Uses of the Web

• In 1991, Commercial Internet Exchange (CIX)
  Association was established to allow businesses
  to connect to the Internet
• Firms use the Internet for many types of
  applications

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E-Mail, Instant Messaging, and Push Technology

• E-mail
• No longer limited to simple text messages
• Can embed sound and images
• Can attach files
• Instant messaging online, real-time
  communication between two or more people who are
  connected to the Internet
• Push technology automatic transmission of
  information over the Internet rather than make
  users search for it with their browsers

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E-Mail, Instant Messaging, and Push Technology
(continued)
Table 7.7 Some Common Abbreviations Used in
Personal E-Mail
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Internet Cell Phones and Handheld Computers

• Cell phones connected to the Internet allow
  people to search for information, buy products,
  and chat with business associates and friends
• Short Message Service (SMS) or texting
• Brief text messages can be sent between two or
  more cell phone users
• Handheld computers and other devices are
  connected to the Internet using phone lines or
  wireless connections

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Career Information and Job Searching

• Use search engines to look for specific companies
  or industries
• Internet sites specialize in helping you find job
  information and apply for jobs online
• Examples www.monster.com, www.hotjobs.com, and
  www.careerbuilder.com

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Telnet and FTP

• Telnet terminal emulation protocol that enables
  users to log on to other computers on the
  Internet to gain access to public files
• File Transfer Protocol (FTP) protocol that
  describes a file transfer process between a host
  and a remote computer and allows users to copy
  files from one computer to another

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Web Log (Blog), Video Log (Vlog), and Podcasting

• Web log or blog Web site that people create and
  use to write about their observations,
  experiences, and feelings on a wide range of
  topics
• Video log or vlog video content placed on the
  Internet using the same overall approach as a
  blog
• Podcast audio broadcast over the Internet
• People and corporations use podcasts to listen to
  audio material, increase revenues, or advertise
  products and services

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Usenet and Newsgroups

• Usenet system closely allied with the Internet
  that uses e-mail to provide a centralized news
  service
• Protocol that describes how groups of messages
  can be stored on and sent between computers
• Newsgroups online discussion groups that focus
  on specific topics

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Chat Rooms

• Chat room enables two or more people to engage
  in interactive conversations over the Internet
• Internet Relay Chat (IRC) requires participants
  to type their conversation rather than speak
• Voice chat allows participants to speak their
  conversation
• Must have a microphone, sound card, speakers, a
  fast modem or broadband, and voice-chat software
  compatible with the other participants

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Internet Phone and Videoconferencing Services

• Internet phone service
• Relatively inexpensive, especially for
  international calls
• Voice-over-IP (VoIP) technology
• Network managers can route phone calls and fax
  transmissions over the same network they use for
  data
• Internet videoconferencing
• Supports both voice and visual communications
• Webcasts or Webinars

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Content Streaming

• Method for transferring multimedia files, radio
  broadcasts, and other content over the Internet
• Data stream of voice and pictures plays more or
  less continuously without a break, or with very
  few breaks
• Enables users to browse large files in real time
• Works best when the transmission of a file can
  keep up with the playback of the file

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Shopping on the Web

• You can shop for almost anything over the
  Internet
• Convenient, easy, and cost effective
• Many Web sites also offer free shipping and
  pickup for returned items
• Bot a software tool that searches the Web for
  information, products, or prices
• Finds the best prices or features from multiple
  Web sites

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Web Auctions

• Web auction Internet site that matches buyers
  and sellers
• Businesses grow or reach customers for a low cost
  per transaction
• One of the most popular auction sites eBay
• Potential problems with auction Web sites
• Auction sites cannot always determine whether the
  people and companies listing products and
  services are legitimate
• Some Web sites have illegal or questionable items
  offered

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Music, Radio, Video, and TV on the Internet

• Audio and video programs play on the Internet or
  download files for later use
• Music players and music formats such as MP3
  download music from the Internet and listen to it
  anywhere
• Musicians can gain exposure without a lucrative
  music contract
• Radio broadcasts
• Audio books

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Music, Radio, Video, and TV on the Internet
(continued)

• Video and TV are increasingly becoming available
  on the Internet
• New, innovative devices let you record TV
  programs and view them at any time and place
• Many content providers offer their programs over
  the Internet

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Office on the Web

• Internet office Web site that contains files,
  phone numbers, e-mail addresses, an appointment
  calendar, and more
• Allows your desktop computer, phone books,
  appointment schedulers, and other important
  information to be with you wherever you are
• Many services and software products give you
  remote access to your files and programs over the
  Internet

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Internet Sites in Three Dimensions

• Some Web sites offer three-dimensional views of
  places and products
• Examples
• 3-D Internet auto showroom allows people to get
  different views of a car
• 3-D real estate site people can tour the
  property, go into different rooms, etc.

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Other Internet Services and Applications

• Libraries provide vast amounts of information
• Movies ordered and delivered over the Internet
• Critical information during times of disaster or
  terrorism
• Translation words, sentences, or complete
  documents from one language into another

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Other Internet Services and Applications
(continued)

• Distance learning online courses
• Internet cameras conduct job interviews hold
  group meetings with people around the world
  monitor young children at daycare centers, etc.
• Connect with friends or others with similar
  interests

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Intranets and Extranets

• Intranet internal corporate network built using
  Internet and World Wide Web standards and
  products
• Used by employees to gain access to corporate
  information
• Reduces the need for paper

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Intranets and Extranets (continued)

• Extranet network based on Web technologies that
  links selected resources of a companys intranet
  with its customers, suppliers, or other business
  partners
• Virtual private network (VPN) secure connection
  between two points across the Internet
• Tunneling process by which VPNs transfer
  information by encapsulating traffic in IP
  packets over the Internet

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Intranets and Extranets (continued)
Table 7.9 Summary of Internet, Intranet, and
Extranet Users
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Net Issues

• Management issues
• Preventing attacks
• Service and speed issues
• Keeping up with Internet traffic and traffic on
  company intranets
• Privacy
• Fraud
• Security
• Unauthorized Internet sites