Slide 1 Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall Power Point Lectures...

Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall

Power Point Lectures to accompany Tomorrow’s Technology and You, 9e

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted,

in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior

written permission of the publisher. Printed in the United States of America.


Tomorrow’s Technology and You 9/e

Chapter 9The Evolving Internet

Slide 3Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall

Tomorrow’s Technology and You 9/e Chapter 9Objectives

Explain how and why the Internet was created

Describe the technology that’s at the heart of the Internet

Describe the technology that makes the Web work as a multimedia mass medium

Discuss the tools people use to build Web sites


Tomorrow’s Technology and You 9/e Chapter 9

Objectives (cont.)

Discuss the trends that are changing the Internet and the way people use it

Discuss some of the most important social and political issues raised by the growth of the Internet

Describe various ways that governments restrict access to the Internet



ARPANET Pioneers Build a Reliable NetworkOut of Unreliable Parts

The ARPANET (Advanced Research Projects Agency NETwork) is the predecessor to the Internet: Developed at the request of the Department of Defense by

a team of visionary computer scientists Launched in 1969 Peer-to-peer networking philosophy and protocols were

copied in othernetworks in the 1980s

Disbanded in 1990, having fulfilled its research mission, but its technology spawned the Internet



Inside the Internet

The Internet: an interconnected network of thousands of networks Links academic, research,

government, and commercial institutions

The Internet2 consortium Will lead to new

applications Faster communications Higher reliability Greater security Will eventually be

incorporated into the existing Internet



Inside the Internet

Counting connections Connects computers to about every

country in the world Growing too fast to measure its growthInternet is decentralizedInternet doesn’t have hard boundaries



Inside the Internet

Internet protocols TCP/IP (Transmission Control Protocol/Internet Protocol)

At the heart of the Internet Allows cross-network communication

TCP breaks messages into packets. Each packet has all the information needed to travel from network to

network. Host systems called routers determine how to route transmissions. Packet switching is flexible and robust.



Inside the Internet

Internet protocols (cont.) IP is the address for the packets.

Each Internet host computer has a unique IP address. Each address is comprised of four sets of numbers

separated by periods, such as 123.23.168.22.NextGeneration Internet will allow more addresses and

multicasting.



Inside the Internet

Internet addresses The host is named using DNS (domain name system), which

translates IP addresses into a string of names. Top-level domains include:

.edu—educational sites .com—commercial sites .gov—government sites .mil—military sites .net—network administration sites .org—nonprofit organization sites



Inside the Internet

Internet addresses (cont.) Top-level domains include: (cont.)

.aero—Air transport organizations .biz—Businesses .coop—Cooperative businesses such as credit unions .info—Information services .museum—Museums .name—Personal registration by name .pro—Licensed professionals, including lawyers,

doctors, and accountants



Inside the Internet

Internet communication An email address includes:

[email protected] username is the person’s “mailbox” hostname is the name of the host computer and is

followed by one or more domains separated by periods:

• host.domain• host.subdomain.domain• host.subdomain.subdomain.domain



Inside the Internet

Slide 14

[email protected]

User President whose mail is stored on the host whitehouse in the government domain

[email protected]

User hazel_filbert at the admin server for Grant MacEwan Community College in Alberta, Canada


Internet communication (cont.)


Inside the Internet

Internet access optionsDirect (Dedicated) Connection

Computer has its own IP address and is attached to a LAN

No need to dial upFiles are stored on your computerQuick response time

Dialup ConnectionLimited connection using a modemFull access dialup uses POTS or PPP via modem



Inside the Internet

Internet access options (cont.) Broadband connections

DSL service • Newer, faster, and cheaper than ISDN• Can share phone line with voice traffic

Cable modem connection• Allows Internet connections using shared TV

cables• Can exceed DSL speeds• Carries increased privacy and security risks



Inside the Internet

Internet access options (cont.) Satellite connection provides connection using DirecTV

satellite dishes. Wireless broadband connection allows multiple

computers to connect to a base station using short-range radio wave.

ISPs (Internet service providers) Local ISPs provide connections through local telephone

lines.National ISPs offer connections on a nationwide scale.Online services like AOL and MSN offer extra services.



Inside the Internet

Internet servers Email server acts like a local post office for a particular

Internet host—a business, an organization, or an ISP. File servers are common within LANs.

Also used to share programs, media files, and other data across the Internet

FTP (File transfer protocol) allows users to transfer files.Download files from remote servers to their computers Upload files to remote computersFile compression saves storage space on disk and saves

transmission time when files are transferred through networks.



Inside the Internet

Internet servers (cont.) Application server stores applications—PC office

applications, databases, or other applications.Makes them available to client programs that

request themMight be housed at an ASP (application service

provider), a company that manages and delivers application services on a contract basis

Web server stores Web pages and sends pages to client Web browsers.



Inside the Web

Web protocols: HTTP and HTML HTTP (Hypertext transfer protocol) used to transfer Web pages.

HTML (HyperText Markup Language) created for encoding and displaying documents.



Inside the Web

Slide 21

HTML is not WYSIWYG (What You See Is What You Get).



Inside the Web

Publishing on the Web Programs that convert document format features into HTML

codes: Microsoft Word, PowerPoint, FileMaker

Web authoring software: Dreamweaver, Apple’s iWeb, Microsoft

Expression Web



Inside the Web

From hypertext to multimedia Typical Web pages can contain:

Slide 23

TablesFramesFormsAnimationsSearch engines

Downloadable audio and video

Real-time live audio or video

3-D environmentsPersonalizationStreaming audio

and video



Inside the Web

From hypertext to multimedia (cont.) Plug-ins and helper applications

Slide 24

RealOneQuickTimeShockwave/FlashRealPlayerAdobe Reader and Acrobat



Inside the Web

Dynamic Web sites: beyond HTML Dynamic HTML

Adds more programming power to HTML by allowing code to modify itself automatically under certain circumstances

Languages for dynamic sites

Perl scripting language

Java: Full-featured, cross-platform, object-oriented programming language



Inside the Web

Dynamic Web sites: beyond HTML (cont.) Java applets: small java programs

Automatically downloaded onto client computer Can run on any platform

ActiveX: collection of programming technologies and tools for creating controls or components

Similar in many ways to Java applets



Inside the Web

Dynamic Web sites: beyond HTML (cont.)

XML (extensible markup language)Will replace HTML plus provide additional features

and extensionsXHTML

A sort of cross between HTML and XML SMIL (synchronized multimedia integration language)

Makes it possible to link time-based streaming media—sounds, video, and animation can be tightly integrated



Inside the Web

Search engines Search engines are designed to make it easier to find information

on the Web.Web crawlers or Spiders

• Software robots that systematically search the Web

Some search engines use keywords and Boolean logic to conduct searches.

Other search engines conduct searches using a hierarchical directory or subject tree.



Inside the Web

Portals Web entry stations that offer quick and easy access to a

variety of servicesConsumer portals include search engines, email

services, chat rooms, references, news and sports headlines, shopping malls, and other services.

Corporate portals on intranets serve the employees of particular corporations.

Vertical portals are targeted at members of a particular industry or economic sector.



Inside the Web

Push technology and RSSThe Web was built with pull technology.

Browsers on client computers “pull” information from server machines.

Essentially, the browser asks for information.With push technology, information is delivered automatically to

the client computer.New product descriptionsAutomatic software upgradesUpdated news

RSS (Really Simple Syndication) pushes (feeds) information to people who read blogs.



Inside the Web

Web 2.0 and you Web 2.0 is the term often used for participatory

technologies.BlogsForumsWikis

Distinguishing feature of Web 2.0 is the do-it-yourself spirit.

Mashup is a Web page, song, video, or image that combines music and video clips from other works.



Inside the Web

Internet issues: ethical and political dilemmas Commercialization of the Internet has opened a floodgate of new

services to users Internet addiction

Excessive Internet usage is a true addiction People spend excessive time on

• Online communities• MMORPG (massive multiplayer online role-playing games)



Internet Issues: Ethical and Political Dilemmas

Freedom’s abuses Commercialization has brought capitalism’s dark side to the

InternetSpam scams

Get-rich-quick hoaxes

Online credit card thefts

Email forgery


Child pornography

Illegal gambling

Online stalking

Fraudulent political schemes



Freedom’s abuses (cont.) Filtering software keeps students out of sites

that contain inappropriate content Electronic money systems allow users to make

online transactions easier and safer Digital signatures use encrypted techniques to

make transactions safer




Access and censorship 1996 Communications Decency Act is one reaction to

online hucksterism and pornography In 2000 Congress passed the Children’s Internet

Protection Act




The digital divide The realization that there is a separation of

people who have easy access to computers, the Internet, and digital information technology and those who don’t

NII (National Information Infrastructure) is an affordable, secure, high-speed network to provide “universal service” for all Americans.




Net neutrality The principle that Internet access should be

free from restrictions related to the type of equipment being connected and the type of equipment being connected and the type of communication being performed with that equipment



From Cyberspace to Infosphere

Cyberspace is the term used to describe such a shared virtual reality, complete with sights, sounds, and other sensation



Lesson Summary

The Internet is a network of networks that connects all kinds of computers around the globe and uses standard protocols to allow Internet communication to occur.

No single organization owns or controls the Internet.

You can connect to the Internet in several ways that provide different degrees of access to Internet services.

Most Internet applications are based on the client/server model.



Lesson Summary (cont.)

The Web uses a set of protocols to make a variety of Internet services and multimedia documents available to users through a simple point-and-click interface.

In addition to Web sites, a variety of applications are built on the protocols of the Internet and the Web. For example, people who use the Web depend on search engines to find the information they need.

Peer-to-peer computing was popularized by music-sharing services, but its applications go beyond music sharing.



Lesson Summary (cont.)

Many businesses are exploring ways to apply P2P technology.

Grid computing goes beyond P2P computing by enabling people to share processor power.

As the Internet grows and changes, issues of privacy, security, censorship, criminal activity, universal access, and appropriate Net behavior are surfacing.


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