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Introduction to Information Technology
2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
Chapter 7:
The Internet, Intranets, and Extranets
Prepared by:
Roberta M. Roth, Ph.D.
University of Northern Iowa
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-1
Chapter Preview
 In this chapter, we will study:
The evolution, operations, and services of the
Internet
The segment of the Internet called the World
Wide Web
Organizational applications of Internet
technology (intranets and extranets)
Specialized Internet applications
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-2
What is the Internet?
 The largest computer network in the world (a
network of networks)
 Information exchange is seamless using open, nonproprietary standards and protocols, within
interconnected networks
 A true democratic communications forum
producing a democratization of information
 Spirit of information sharing and open access
underlies the Internet.
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
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The Internet Today
 The Internet is international, with users on all
continents
 The cost of personal computers and Internet
connections are prohibitively high for most of the
world’s population
 Political, cultural, and regulatory barriers have
slowed the rate of Internet adoption
internationally
 The vast majority of sites are in English
 The vast majority of content is generated in the
United States
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
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The Infrastructure of the Internet
 Commercial communications companies are
primary providers of the physical network
backbone of the Internet
 The U.S. government contributes some funds to
essential administrative processes
 The Internet infrastructure is supplied by network
service providers
 Connections between and flow of information
between backbone providers has been open and
free of charge
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
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Future Internet Initiatives
 Internet2
 A collaboration among more than 180 U.S. universities
to develop leading-edge networking and advanced
applications for learning and research.
 A group of very high bandwidth networks on the
Internet.
 Partnership between universities, industry, and
government.
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
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The Operation of the Internet
 Packets of information flow between machines governed
by common rules (protocols):
 Internet protocol (IP)
 Transport control protocol (TCP)
 Internet is a packet-switching network
 Messages are decomposed into packets, containing part of the
message, plus information on the sending and receiving machines
and how the packet relates to the other packets
 Packets travel independently and possibly on different routes
through the Internet
 Packets are reassembled into the message at the receiving
machine.
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-7
The Operation of the Internet (continued)
 Each computer on the Internet is identified by an
IP address
 Many computers also have domain names
 Network Solutions, Inc. had a monopoly on
domain name registration until 1999.
 Today, some 82 companies can register domain
names.
 Cybersquatting – purchase of domain name with
intent to resell it. Legislative action resulted in
Nov. 2000
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-8
The Operation of the Internet (continued)
 New top-level domain zones: In November 2000,
the first addition of a global top-level domains to
the Internet since the 1980s occurred.
 .aero (for the air-transport industry)
 .biz (for businesses)
 .coop (for cooperatives)
 .museum (for museums)
 .name (for individuals)
 .pro (for professionals).
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-9
The Operation of the Internet (continued)
Accessing the Internet
Connect via LAN Server
Connect via an Online Service (AOL,
MSN, GlobalEyes)
Connect directly to a backbone provider
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-10
Internet Services - Communications
 E-mail – electronic
messaging
 USENET newsgroups –
forums that collect groups of
messages from users based on
common themes
 LISTSERV – distributes email
messages to all subscribers
 Chatting – live, interactive,
written conversations based on
topic groups
 Instant messaging – instant
text messaging between
Internet users
 Telnet – user on one
computer doing work on
another computer
 Internet telephony –
conducting voice conversations
over the Internet
 Internet fax – real time
document transmittal
 Streaming audio and
video
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
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Internet Services – Information Retrieval
 File Transfer Protocol (FTP) – electronic transfer of
files from one computer to another
 Archie – tools to enable searching for files at FTP sites
 Gophers – menu-driven information search tool
 Veronica – text search through Gopher sites
 Wide Area Information Servers (WAIS) – database
search tool
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
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Internet Services – Web Services
 Delivery of software components via a web
site rather than through traditional means
(disks, CDs)
 .NET – Microsoft’s new platform for XML Web
services. Integrates web sites and programs to
deliver applications.
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-13
Internet Services – World Wide Web
 An application that uses the Internet transport
functions
 A system with universally accepted standards for
storing, retrieving, formatting, and displaying
information via a client/server architecture
 Based on HTML - standard hypertext language
used in Web
 Handles text, hypermedia, graphics, and sound
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-14
The World Wide Web (continued)
 Home Page - a text and graphical screen display; first,
introductory page in a web site
 Web Site - all the pages of a company or individual
 Hyperlinks - ways to link and navigate around the
pages on a web site
 Webmaster - the person in charge of a Web site
 Uniform Resource Locator (URL) - points to the
address of a specific resource on the Web
 Hypertext Transport Protocol (HTTP) communications standard used to transfer pages across
the WWW portion of the Internet
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-15
The World Wide Web (continued)

Browsers – graphical software that enables WWW users to request
and view web documents

Offline Browsers – software that retrieves pages from Web sites
automatically at predetermined times

Search Engines - programs that return a list of Web sites or pages
that match some user-selected criteria

Metasearch Engines - automatically enter search queries into a
number of other search engines and return the results

To be included in a search engine’s database


Web Crawlers
Registration
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-16
The World Wide Web (continued)
 Pull Technology - requires web user to actively request
information; traditional web mechanism
 Push Technology - automatically supplies desirable
information to users
 provides timely, prioritized distribution of information
over a corporate network in the workplace
 enhances traditional Web advertising in the consumer
market
 used for software delivery and updates
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-17
The World Wide Web (continued)
 Information Filters – automated methods of
sorting/screening WWW content
 Clipping Services – automated retrieval of articles and
news items from publications
 Personalized Web Services – ability to generate
personalized Web content
 Web Authoring (for page and site design)
 Standard HTML is the common denominator
 CompuServe Graphics Interchange Format (GIF) and Joint
Photographic Experts Group (JPEG) is the common format of
graphics files
 Browsers can be extended through software plug-ins
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-18
Internet Challenges
 Internet Privacy - Web sites collect information with and
without consumers’ knowledge
 Cookie - small data file placed on users’ hard drives when a
site is first visited. Collects data on pages visited and content
viewed.
 Three potential approaches to the privacy issue
• Government lets groups develop voluntary privacy standards;
does not take any action now unless real problems arise
• Government recommends privacy standards for the Internet;
does not pass laws at this time
• Government passes laws now for how personal information
can be collected and used on the Internet
 Financial transaction security also a concern
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-19
Intranets
 A private network that uses Internet
software and TCP/IP protocols
Provide employees with easy access to
corporate information
Used to deploy corporate applications
• Examples – policies and procedures manuals;
human resource forms; product catalogs
Security is a concern
• Security measures include – public key security,
encryption, digital certificates, firewalls
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-20
Extranets
 An extension of an intranet to selected outside
business partners, such as suppliers, distributors,
and key customers
 Provide business partners with easy access to corporate
information and easy collaboration
 Security
 Critical to prevent unwanted entry into internal systems
 Virtual private networks (VPNs) are often used to add
security to Internet communication
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-21
Extranets (continued)
 Extranet configurations
 One company sets up a Extranet for its dealers,
customers, or suppliers
 Companies within an industry set up a collaborative
Extranet for mutual benefit
 Several companies collaborate over an Extranet for
joint venture
 Benefits include –
 Lower communication costs; better communication;
improved order entry and customer service;
improvement in business effectiveness
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-22
Chapter Summary
 Internet is a network of networks
 Internet provides communication and information
retrieval services, as well as the World Wide Web
 The World Wide Web enables a huge variety of
applications for businesses, including intranets and
extranets
 Many challenges exist when using the WWW,
including congestion, privacy, and security
Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-23
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Introduction to Information Technology, 2nd Edition
Turban, Rainer & Potter
© 2003 John Wiley & Sons, Inc.
7-24