understanding the internet chapter 1 learn how to… define the internet, describe how large the...

Understanding the Internet

Chapter 1

Learn how to…

• Define the Internet, describe how large the Internet is, and compare its explosive growth.

• Identify the most popular Internet services.• Describe underlying concepts of the Internet.• Define how the Internet impacts everyday life.• Provide a brief history of the Internet.• Describe efforts under way to improve the

Internet.

CIW

• CIW stands for Certified Internet Webmaster.

• To certify, you have to pass an exam proctored by an independent testing firm.

• The exam covers:– Internet Fundamentals– Web Page Authoring Fundamentals– Networking Fundamentals

Defining the Internet

Defining the Internet

• The Internet is a worldwide connection of more than 171 million computers.

• It uses the Internet Protocol (IP) to communicate.

• Invented for the Advanced Research Projects Agency (ARPA) of the U.S. Department of Defense.

• Used to create a decentralized network that could continue to function even if part of it was taken out by a nuclear bomb.

Traffic on the Internet

• Traffic volume is depicted by the lines.– Purple lines indicate 0 bytes– White lines indicate 100 billion bytes

Who uses the Internet

• People from all walks of life use the Internet.

• The Internet is growing at a phenomenal rate.

Identifying Eleven Popular Internet Services

Internet Services

The most popular services on the Net are:– Electronic Mail (e-mail).– Listserv– Newsgroups– Chat– Videoconferencing– File Transfer Protocol (FTP)– Multimedia Streaming– World Wide Web– Rich Site Summary (RSS)– Blogging

Electronic Mail (e-mail)

• Mails queue up in your mailbox.

• Users read and respond at their convenience.

Listserv

• Listserv stands for List Server• It works like an electronic mailing list.• Users subscribe and then receive a copy of any

e-mail sent to the list.• Electronic magazines (e-zines) are distributed

using listservs.

Newsgroups

• Newgroups are an electronic bulletin-board service.

• They contain discussions on any topic.

• A newsreader is used to access a newsfeed.

Chat

• Real-time communications in chat rooms• Users type messages back and forth.

Instant Messaging (IM)

• Instant Messaging (IM) allows you to keep in contact with friends or associates.

• When someone on your buddy list wants to talk to you, an instant message appears on your screen.

Video Conferencing

• Video conferencing uses a video camera and a microphone to allow people to see and hear each other.

• Because of high bandwidth demands, it is not yet as popular as text-based messaging.

FTP

• File Transfer Protocol (FTP) is used to transfer files over the Internet from one computer to another.

Multimedia Streaming

• Streaming is the digital transmission of multimedia content in real time over the Internet.

• Only the amount of data needed to continue playing is stored in a buffer in memory.

• Many radio stations stream their programming live over the Internet.

World Wide Web (WWW)

• A hypertext system that allows documents to be shared over the Internet.– Hypertext refers

to text that has been linked.

Browsers

• Mosaic is a graphical user interface that made the Internet extremely easy to use.– Web pages may display pictures.– Links to audio and video may be included.

• Netscape Navigator was soon released and became the most popular Web browser.

• Microsoft introduced Internet Explorer.

W3C

• W3C is the World Wide Web Consortium.– It coordinates the research and development

of new standards and features for the Web.

Rich Site Summary

• Rich Site Summary (RSS) allows syndicating of a Web site in a form that can be registered with an RSS publisher.

• Other sites can subscribe to the Web site to access the RSS feed from an RSS publisher.

• Uses eXtensible Markup Language (XML).

Blogging

• Blog is short for Web log.– A Web-accessible log is written by someone

who wants to chronicle activity related to a given topic (often personal).

– It is essentially keeping your diary online.

Describing the Infrastructure of the

Internet

Client-Server Computing

• The Internet is made up of computers that send and receive information in a client-server environment.– Servers send information.

• Servers devoted to sending Web pages are called Web servers.

– Clients receive information.• When you search the Web using a Web browser,

your computer is a client.

TCP/IP

• Information is transmitted over the Internet in units called packets.

• TCP and IP are two protocols required to send packets.

• Transmission Control Protocol (TCP) is used to break large packets into smaller ones.

• Internet Protocol (IP) handles the addressing and routing of packets.

IP Addresses

• IP uses IP addresses to identify computers.

• Each packet contains the source and destination IP addresses.

• IP addresses consist of four 8-bit bytes ranging from 0 to 255.

• IP addresses are often expressed in dotted quad notation.– Example: 140.147.249.7

DNS

• DNS stands for Domain Name System.

• DNS allows you to use alphanumeric characters instead of numbers for IP addresses – making it easier to remember them.– For example, www.loc.gov can be used

to reach the Library of Congress instead of remembering 140.147.249.7.

FQDN

• A complete DNS address is called a Fully Qualified Domain Name (FQDN).– FQDNs have the format

hostname.registered-domain-name.top-level-domain.

Top-Level Domains

• Top-Level Domains (TLD) in the United States include:

• In the rest of the world, TLDs are usually country codes.

TLD Country Codes

Domains

• Domain refers to the network to which a computer is connected.

• Host name refers to the computer itself.• A domain can be subdivided into subdomains.• Possible formats are:

– hostname.registered-domain-name.second-level-domain.top-level-domain

– hostname.subdomain-name.registered-domain-name.top-level-domain

ICANN

• ICANN stands for Internet Corporation for Assigned Names and Numbers.– Assigns domain names, IP addresses,

protocol parameters, and port numbers.

Intranet

• An Intranet is a network that uses the TCP/IP protocols to provide private services within an organization.– It uses Internet technology within a private

network.

Extranet

• Extranet refers to Internet resources that are beyond the reach of the public and require a logon name and password to access.

Changing the World via the Internet

Convergence

• Convergence is the process of unification that digitalization causes by enabling all the world’s traditional ways of communicating to work over a common communications medium on the Internet.

• Digital divide refers to barriers faced by the unconnected.

Mergers and Alliances

• Corporate mergers and alliances have occurred as a result of the Internet and the digitalization of communication.

Telecommuting

• Telecommuting is the act of working from home by using computers, dial-up modems, or broadband network connections, and fax machines to perform work that formerly required a person to travel physically to work.– A person who telecommutes is a teleworker.

Business & Advertising

• The Internet has become a utility for businesses to advertise and market their products.– Companies offer free services to entice

people to visit their Web site more often.– Pop-under (appear under an opened Web

page) and pop-up (appear on top of an opened Web page) advertises are very common.

Online Shopping

• Teleshopping is purchasing products online.– Fifty-seven percent of adults shopped online

in 2001.

Online Banking

• Now, you can pay your bills online with online banking.

• You can also invest your money and manage your portfolio online.

Government Services

• The Net makes government services more widely available.

Politics

Information Warfare

• Information warfare is an electronic attack or invasion of computer networks.– The Department of Defense is prepared to

disconnect its worldwide network from the Internet if necessary.

Homeland Security

• The USA Patriot Act gives wide latitude to the government in using Internet surveillance systems.– Terrorists use the Internet to hide secret

messages.– The FBI uses a system called Carnivore

to intercept suspicious e-mails.

Electronic Publishing

• Electronic book (eBook) technology allows publishers to sell books in electronic format.– eBooks are in a full text searchable format.

Television & Entertainment

• The Internet competes with television for people’s free time.

• You can find TV listings on the Internet.

• Interactive TV merges the Internet and television.– Play along with Wheel of Fortune or Jeopardy.– Vote for your choice on Judge Judy.

Teaching and Learning

• Computer-based learning strategies lead to faster and better learning.

• Learning can be customized to the individual student.

Tracing the History of the Internet

Origin of the Internet

• The Internet began when the Advanced Research Projects Agency (ARPA) of the Department of Defense (DoD) began a network called ARPANET in 1969.– DOD wanted a network that could survive

a nuclear attack without stopping communication.

Colleges and Universities

• In the 1970s, colleges and universities connected to ARPANET using IP.– In 1983, the military part broke off and

became MILNET.

• In 1986, the National Science Foundation (NSF) began NSFNET to connect the nation’s five supercomputer centers.– In 1991, commercial entities were allowed

to connect to NSFNET.

Internet Backbone & DNS

• In 1995, NSFNET reverted to research; the Internet backbone traffic began to be routed through network providers.

• In 1998, the U.S. government turned over management of the domain name space from InterNIC to ICANN.

Internet2

• Declining cost and explosive growth in using the Internet has spurred research into a faster network called Internet2.

Looking Into the Future of the Internet

Improving the Infrastructure

• Multicast backbone (MBONE) is a network of computers on the Internet specifically designed for the transmission of simultaneous live video and audio broadcasts.

Streaming Media

• Streaming media network vendors bring uninterrupted audio and video streams to end users.– Streaming media is fed directly to edge

servers located near local ISPs.

Streaming Media

Internet2

• Internet2 is a project to create a higher-speed Internet. – Utilizes high-speed connection points called

gigapops.– Resource Reservation Protocol (RSVP)

reserves bandwidth from workstation to host computer.

– Internet Protocol version 6 (IPv6) allows users to assign priorities to certain traffic.

– Multicast increases multimedia throughput.

Wireless Communications

• Wireless technologies no longer require a cable to connect to the Internet.– Motorola’s 200 Smartphone

brings the Internet to the palm of your hand.

Bluetooth

• Bluetooth is an emerging standard for high-speed wireless communication.– It enables

communication among mobile computers, telephones, handheld devices, and the Internet.

Wi-Fi

• Wi-FI is a trade name based on IEEE 802.11 specification for wireless local area networking.

• Wi-Fi access points are called HotSpots, an area over which you can connect.

• FreeSpots are locations that offer free wireless Internet access.– Examples: Hotels, coffee shops, restaurants,

and airports

IP Telephony

• IP telephony merges the public switched telephone network (PSTN) with IP.– It converges voice, video, and data into one

network using Voice-over IP (VoIP).– Microsoft’s Telephone Application Program

Interface (TAPI) enables Windows users to use IP telephony.

– IP telephone calls are much cheaper than normal long-distance calls.

Personal Digital Assistants

• Personal digital assistants (PDAs) are portable, handheld computers.

• Windows CE– A compact module

version of Microsoft Windows

– Example: Toshiba’s PocketPC

• Palm OS– Created by Palm, Inc.

specifically for a small device

Artificial Intelligence

• Artificial Intelligence (AI) includes:– Voice recognition– Text-to-Speech conversion– Foreign language translation– Image recognition– Bots

Voice Recognition

• Voice recognition allows software to recognize your voice and respond.– Voice-controlled Web surfing, legal dictation,

environmental control systems, and word processing.

Text-to-Speech Conversion

• Text-to-speech conversion allows you to hear conversations and see them.

Foreign Languages

• Foreign language translation can translate Web pages, e-mail, chat, and other documents between languages.

Image Recognition

• Image recognition software can compare images using a visual template.– Search for images based on visual properties.

Bots

• Bots, short for robots, are software applications programmed to act as intelligent agents that go out on the network to find or do things for you.

Digital TV and Video

• Digital televisions provide a high-resolution display screen that can integrate computer data, Web pages, and television broadcasts.

HDTV

• High-Definition Television (HDTV) is based on:– MPEG digital video compression– Transmission in packets that permit any

combination of video, audio, and data– Progressive scanning for computer

interoperability up to 60 frames per second (fps) at 1920 × 1080 pixels

– CD-quality digital surround sound using Dolby AC-3 audio technology

MPEG Digital Video

• The Motion Pictures Experts Group (MPEG) developed the MPEG standard.– Eliminates redundant data in images.– Uses delta-frame encoding to record only

the changes from one frame to another.

MSN TV

• An MSN TV Internet receiver is a device that combines your telephone with the video signal on your TV or VCR.– See Web pages on

your TV screen.– Sometimes called

telecomputer.

Ultimate TV

• UltimateTV allows you to record your favorite shows without a VCR, pause live television, create your own TV program line-up, and instantly replay anything you see on TV.

Digital Hubs

• Your personal PC will become a digital hub that coordinates all of the electronic devices in your home.– Play music in other rooms from your PC.– Distribute video streams to receivers throughout

your home.– Print digital camera photos without plugging

anything.– Keep an eye on your home while you are away

over the Internet.– Remote control all of your home appliances.