CHAPTER 6
Networks
Chapter Outline
6.1 What Is a Computer Network?
6.2 Network Fundamentals
6.3 The Internet and the World Wide Web
6.4 Network Applications
Learning Objectives
1. Define the term computer network, and
compare and contrast the two major types of
networks.
2. Describe the differences among the three
types of wireline communications media, and
discuss the main advantages and
disadvantages of each type.
3. Differentiate between the Internet and the
World Wide Web, and describe the most
common methods for accessing the Internet.
Learning Objectives (continued)
4. Identify six major categories of network
applications, provide an example of each, and
explain how that application supports business
functions.
6.1 What Is a Computer Network?
In a computer network,
connected computers:
Work together
Are interdependent
© Ilin Sergey/Age Fotostock America, Inc.
Exchange data with
each other
Broadband
Coaxial cable
Source: GIPhotoStock/Photo Researchers, Inc
Fiber optics
Source: Philip Hatson/Photo Researchers, Inc
Size of Computer Networks
Home computer network
National computer network
Global computer network
Local Area Networks
Wide Area Networks
© Ilin Sergey/Age Fotostock America, Inc.
Enterprise Network
6.2 Network Fundamentals
Analog and Digital Signals
Communications Media and Channels
Transmission Technologies
Network Protocols
Types of Network Processing
Analog and Digital Signals
Communications Media and Channels
Twisted-pair wire
Coaxial cable
Fiber optics
Sources: deepspacedave/Shutterst ock, GIPhotoStock/Photo Researchers, Inc, Philip Hatson/Photo Researchers
Transmission Technologies
Digital subscriber line (DSL)
Asynchronous transfer mode (ATM)
Synchronous optical network (SONET)
T-carrier system
Network Protocols
Ethernet
Transmission Control Protocol/Internet
Protocol (TCP/IP)
The Four Layers of the TCP/IP Protocol
Packet Switching
Types of Network Processing
Client/server computing
© Matthias Pahl/Age Fotostock America, Inc.
Peer-to-peer processing
© Toh Kheng Ho/Age Fotostock America, Inc.
6.3 The Internet and the World Wide Web
Accessing the Internet
The Future of the Internet
The World Wide Web
Image of the Internet
in the United States
Source: © Mark Stay/iStockphoto)
An Intranet
© Corbis/Age Fotostock America, Inc.
Accessing the Internet
Connecting via an online service
Internet kiosks
Dial-up
DSL
Accessing the Internet
Cable Modem
Satellite
Wireless
Fiber to the Home
Addresses on the Internet
IPv4
32 bits
IPv6
128 bits
Addresses on the Internet
Domain names
Top-level domain
Name of the organization
Name of the specific computer
Internet Address example
www.business.auburn.edu
Name of the specific
computer: business
Name of the
organization:
Auburn University
Top level domain:
edu
The Future of the Internet
Source: © Mark Stay/iStockphoto)
The World Wide Web
The World Wide Web
Not the same thing as the Internet
Home page
Uniform resource locator
© Ilin Sergey/Age Fotostock America, Inc.
Browser Competition
© Matthias Pahl/Age Fotostock America, Inc.
6.4 Network Applications
Discovery
Communication
Collaboration
E-Learning and Distance Learning
Virtual Universities
Telecommuting
Discovery
Search engines
Metasearch engines
Discovery of material in foreign languages
Portals
Four Large Search Engines
The largest search engines are:
•Google
•Yahoo
•Bing
© Claver Carroll/Age Fotostock America, Inc.
•Baidu
Metasearch Engines
Figure 4.10 The KartOO home page (www.kartoo.com)
Publication of Material in Foreign Languages
Portals

Commercial (public) portals

Affinity portals

Mobile portals

Corporate portals

Industry wide portals
Affinity Portal (example)
Figure 4.12 University of West Georgia affinity portal. (Courtesy of West Georgia University.)
Industrywide Portal (example)
Figure 4.13 The TruckNet portal
Communication
Electronic mail (e-mail)
Web-based call centers (customer call
center)
Electronic chat room
Voice
Unified
© Mario S Ragma Jr/Age Fotostock America, Inc.
Electronic Mail
Source: Stockphoto4u/iStockphoto
Call Centers
© Dinodia/Age Fotostock America, Inc.
Voice Communication
Two examples of Internet telephony (VoIP)
Skype
Vonage
Collaboration
Work group
Virtual group (team)
Source: Howard Kingsnorth/The Image
Bank/Getty Images, Inc.
Collaboration (continued)
Virtual collaboration
Collaboration software
Electronic Teleconferencing
E-Learning and Distance Learning
Crowdsourcing
© YURI ACURS/Age Fotostock America, Inc.
Software products supporting collaboration
Microsoft Sharepoint
IBM Lotus Quickr
Google Docs
Jive Software
Telepresence Systems
Source: PRNews Foto/Polycom, Inc./NewsCom
See video on Cisco Magic
E-Learning and Distance Learning
E-Learning
Distance learning
Source: Mike Flippo/Shutterstock
Benefits of E-Learning
 Self-paced learning increases content
retention.
 Online materials deliver high-quality, current
content.
 Students have the flexibility of learning from
any place at any time at their own pace.
 Learning time generally is shorter, and more
people can be trained due to faster training
time.
 Training costs can be reduced.
Drawbacks of E-Learning
 Instructors may need training to be able to
teach electronically.
 The purchase of additional multimedia
equipment may be necessary.
 Students must be computer literate and may
miss the face-to-face interaction with
instructors.
 There are issues with assessing students’
work, as instructors really do not know who
completed assignments.
Telecommuting
Source: © Maria R.T. Deseo/PhotoEdit
Telecommuting Benefits
 For Employees


Reduced stress, improved family life
Employment opportunities for single parents
and persons with disabilities
 For Employers


Increased productivity
Ability to retain skilled employees
Telecommuting Disadvantages
 For Employees



Feelings of isolation
No workplace visibility
Potential for slower promotions
 For Employers



Difficulties in supervising work
Potential information security problems
Additional training costs
Chapter Closing Case
• The Problem
• The Solution
• The Results