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Ying WangEND 303Fall 2008
ObjectivesDefine communicationsIdentify the basic components of a
communications systemDescribe how and why network computers
are used in schools and school districtsExplain how the Internet works
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ObjectivesDescribe the World Wide Web portion of the
InternetExplain how Web documents are linked to
one anotherExplain the use of Web browser softwareExplain how to use a Web search tool to find
information
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What Is Communications?A process in which two or more computers or
devices transfer data, instructions, and information
Sometimes called telecommunications
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What Is Communications?Electronic mail (e-mail)Voice mailFax (facsimile)TelecommutingOnline servicesVideoconferencingInternetWorld Wide Web
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Communications NetworksBasic communications system
Two computers, one to send and one to receive data
Communications devices that send and receive data
A communications channel over which data is sent
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Communications Networks
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Communications channelTransmissions media
Twisted-pair cable
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Communications Networks
Digital vs. analog signalsModem
External modemInternal modem
Network interface cards
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Communications Networks
Communications NetworksLocal Area Networks (LAN)
Covers limited geographical areaServer manages resources
Wide Area Networks (WAN)Covers large geographical areaCan consist of several LANs
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Home NetworksConnects multiple
computers in your home
Share Internet access
Share peripheralsCan be wired or
wireless
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Communications Networks
School network serverExample classroom
Three Macintosh computers
PrinterExample school
networkClassroomsAdministrationComputer lab
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Networking the Classroom, School, and District
Networking the Classroom, School, and District
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Networking the Classroom, School, and DistrictExample school district
Central officeVarious schools
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Wireless schools and classroomsKeep in touch with
family and friends from anywhere Smart pagers Smart phones Handheld computers Notebook computers
Wireless technology brings the computer lab to students
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Networking the Classroom, School, and District
Networking the Classroom, School, and DistrictHigh-Speed or Broadband Access
Government works to provide high speed Internet access to classrooms
Broadband technology transmits signals at much faster speeds
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Sharing of computer hardware, software, and data resources
Unlimited educational resources
Communicate with other educators and students
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The Benefits of Computer Networks in Education
What Is the Internet?Worldwide group of connected networks that
allow public access to information and services
No single organization owns or controls Estimated over one billion usersVariety of users
Chapter 2: Communications, Networks, the Internet, and the World Wide Web 18
What Is the Internet?
Chapter 2: Communications, Networks, the Internet, and the World Wide Web 19
History of the InternetStarted as a network of four computers at the
University of California at Los Angeles in 1969
Advanced Research Projects Agency (ARPA) - ARPANET
More than 350 million computers todayBackbone first provided by National Science
Foundation (NSF) - NSFnet
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History of the Internet
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History of the InternetBackbone now provided by variety of
corporationsVarious organizations help define standardsInternet2 (I2)
Extremely high-speed networkDevelop and test latest Internet technologiesMembers include more than 200 universities in
the United States, along with 70 companies and
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How the Internet WorksData is divided into packetsRouters send packets across the InternetPacket switchingTransmission control protocol/Internet
protocol (TCP/IP) is the communications protocol used by the Internet
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How the Internet Works
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How the Internet WorksInternet Service Providers, Online Service
Providers, and Wireless Internet Service ProvidersHave permanent connections to the InternetProvide temporary connections to individuals
and companies for a feeRegional and national ISPsOnline service providers offer members only
areas
Chapter 2: Communications, Networks, the Internet, and the World Wide Web 25
How the Internet WorksConnecting to the Internet
Business or school network connected to the Internet
Dial-up accessCable TV (CATV)Digital subscriber line (DSL)Power line communications (PLC)Public Internet access point
Chapter 2: Communications, Networks, the Internet, and the World Wide Web 26
How the Internet Works
Chapter 2: Communications, Networks, the Internet, and the World Wide Web 27
How the Internet WorksThe Internet Backbone
Acts as a highwayNational ISPs use dedicated lines to connect
directly to the InternetRegional ISPs connect through leased lines to
national ISPs
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How the Internet Works
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How the Internet WorksInternet Addresses
Numeric addressesDomain name
Domain type abbreviations Country code abbreviations
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Started in the early 1990s
HyperlinksUniform Resource
Locator (URL)Hypertext transfer
protocol
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The World Wide Web
How a Web Page WorksHypertextHyperlinks
Target Relative Absolute
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The World Wide Web
The World Wide WebDiscovery learningWeb surfingWebmasterHypertext markup language (HTML)Web publishing
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Web Browser SoftwareInterprets HTML
and displays Web pages and enables you to link to other Web pages and Web sites
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The World Wide Web
The World Wide WebWeb Browser SoftwareMosaicNetscape NavigatorWindows Internet
Explorer
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Searching for Information on the WebDirectory maintained
by a search engine company
Helps find information on the Web
Search engineSubject directory
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The World Wide Web
The World Wide WebMultimedia on the Web
Web pages incorporate graphics, animation, audio, video, and virtual reality
Plug-ins
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Multimedia on the WebGraphics
Used to enhance text-based Internet
Graphics formats
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The World Wide Web
Multimedia on the WebGraphics
Used to enhance text-based Internet
Graphics formats Thumbnails
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The World Wide Web
The World Wide WebMultimedia on the Web
Animation Marquees Animated GIFs
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Multimedia on the WebAudio
MP3, WAV, and WMA Players
Streaming audio RealAudio Podcasting RSS
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The World Wide Web
Multimedia on the WebVideo
Streaming video
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The World Wide Web
Multimedia on the WebVirtual Reality
Simulation of real or imagined environment that appears as a three-dimensional (3-D) space
VR worlds
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The World Wide Web
Other Internet ServicesE-mail
Primary communication method for both personal and business use
E-mail programs Mailbox Mail server
E-mail address User name
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FTP (file transfer protocol)FTP sites and
serversAllows file
downloads and uploads
Anonymous FTPFTP programs
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Other Internet Services
Other Internet ServicesNewsgroups and Message Boards
Online area in which users conduct written discussions about a particular subject
UsenetNews serverArticlePostingThreaded discussionMessage board
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Other Internet Services
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Other Internet ServicesMailing Lists
Group of e-mail names and addresses given a single name
Subscribing and unsubscribingLISTSERVs
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Instant MessagingSee when one or
more people are online
Exchange messages and files
Join a private chat room
Text messagingShort Message
Service (SMS)
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Other Internet Services
Other Internet ServicesChat RoomsReal-time conversationChat roomsChat clients
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Other Internet ServicesInternet telephony
Voice over IP
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Internet etiquetteThe code of acceptable
behaviors users should follow while on the Internet
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Netiquette
Internet SecurityFirewallFiltering softwareAcceptable Use Policy (AUP)
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The Web is the Gutenberg printing press of modern times
Collaboration with other teachers and studentsePALS
New instructional strategies
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The Impact of the Internet and the World Wide Web on Education
The Future of the Internet and the World Wide WebIn the next few years, the Internet will connect
most of the world’s computersBy 2009, more than one billion wireless
communication devices will be in use worldwide, and many of these products will have the ability to access the Web wirelessly
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SummaryDefine communicationsIdentify the basic components of a
communications systemDescribe how and why network computers
are used in schools and school districtsExplain how the Internet works
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Chapter SummaryDescribe the World Wide Web portion of the
InternetExplain how Web documents are linked to
one anotherExplain the use of Web browser softwareExplain how to use a Web search tool to find
information
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Chapter SummaryIdentify several types of multimedia products
available on the WebExplain how Internet services such as e-mail,
newsgroups, chat rooms, and instant messaging work
Describe the educational implications of the Internet and the World Wide Web
Describe different ways to connect to the Internet and the World Wide Web
58
