Communications, Networks, the Internet, and the World Wide Web

1. Chapter 2 Communications, Networks, the Internet, and the World Wide Web

2. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 2 Chapter Objectives Define communications Identify the basic components of a communications system Describe how and why network computers are used in schools and school districts Explain how the Internet works

3. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 3 Chapter Objectives Describe the World Wide Web portion of the Internet Explain how Web documents are linked to one another Explain the use of Web browser software Explain how to use a Web search tool to find information

4. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 4 Chapter Objectives Explain 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

5. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 5 A process in which two or more computers or devices transfer data, instructions, and information Sometimes called telecommunications What Is Communications?

6. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 6 What Is Communications? Electronic mail (e-mail) Voice mail Fax (facsimile) Telecommuting Online services Videoconferencing Internet World Wide Web

7. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 7 Basic 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 Communications Networks

8. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 8 Communications Networks

9. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 9 Communications channel Path that data follows Transmissions media Twisted-pair cable (most common) Coaxial cable Fiber-optic cable Microwave Satellite Wireless Communications Networks

10. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 10 Communications Networks Digital vs. analog signals Digital: individual electrical pulses Analog: continuous electrical wave Modem (converts the signals; modulates & demodulates signal) External modem Internal modem Network interface cards

11. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 11 Local Area Networks (LAN) Covers limited geographical area Server manages resources Wide Area Networks (WAN) Covers large geographical area Can consist of several LANs Communications Networks

12. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 12 Home Networks Connects multiple computers in your home Share Internet access Share peripherals Can be wired or wireless Communications Networks

13. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 13 Networking the Classroom, School, and District School network server Example classroom Three Macintosh computers Printer Example school network Classrooms Administration Computer lab

14. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 14 Sharing of computer hardware, software, and data resources Unlimited educational resources Communicate with other educators and students The Benefits of Computer Networks in Education

15. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 15 Worldwide group of connected networks that allow public access to information and services No single organization owns or controls Estimated over one billion users Variety of users What Is the Internet?

16. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 16 What Is the Internet? (Fig. 2-11)

17. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 17 Started as a network of four computers at the University of California at Los Angeles in 1969 Advanced Research Projects Agency (ARPA) - ARPANET More than 200 million computers today Backbone first provided by National Science Foundation (NSF) - NSFnet History of the Internet

18. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 18 History of the Internet (Fig. 2-13)

19. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 19 Backbone now provided by variety of corporations Various organizations help define standards Internet2 (I2) Extremely high-speed network Develop and test latest Internet technologies Members include over 190 universities in the United States, along with 60 companies and the United States government History of the Internet

20. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 20 Data is divided into packets Routers send packets across the Internet Packet switching (breaking info into individual packets for “best route” transmission) Transmission control protocol/Internet protocol (TCP/IP) is the communications protocol used by the Internet and thereby defines packet switching How the Internet Works

21. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 21 How the Internet Works (Fig. 2-14)

22. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 22 Internet Service Providers (ISPs), Online Service Providers (OSPs), and Wireless Internet Service Providers (WISPs) Permanently connected to the Internet and provide connections to individuals and companies for a fee Regional ISPs provide access in limited geographical areas, using slow-speed dial-up Online service providers, such as AOL and MSN offer members-only services for an added fee National ISPs provide access in cities and towns, often through high-speed cable or DSL Wireless ISPs service mobile computers/devices How the Internet Works

23. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 23 How the Internet Works Connecting to the Internet Business or school network connected to the Internet Dial-up access ISDN Cable TV (CATV) Digital subscriber line (DSL) Power line communications (PLC) Public Internet access point

24. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 24 How the Internet Works (Fig. 2-16)

25. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 25 How the Internet Works The Internet Backbone Acts as a highway National ISPs use dedicated lines to connect directly to the Internet Regional ISPs connect through leased lines to national ISPs

26. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 26 How the Internet Works (Fig. 2-17)

27. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 27 How the Internet Works Internet Addresses Numeric addresses Domain name Domain type abbreviations Country code abbreviations

28. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 28 How the Internet Works (Fig. 2-19)

29. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 29 The World Wide Web Started in the early 1990s Hyperlinks Uniform Resource Locator (URL) Hypertext transfer protocol (http://)

30. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 30 How a Web Page Works Hypertext Hyperlinks Target (same document) Relative (same computer) Absolute (different document & computer) The World Wide Web

31. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 31 The World Wide Web Discovery learning (branching or non-linear) Web surfing (going from web site to web site) Webmaster (develops and maintains web sites) Hypertext markup language (HTML) Web publishing (putting web sites on the Internet via a server)

32. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 32 The World Wide Web (Fig. 2-22) Web Browser Software Interprets HTML and displays Web pages and enables you to link to other Web pages and Web sites

33. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 33 The World Wide Web Web Browser Software Mosaic Netscape Navigator Microsoft Internet Explorer Mozilla Firefox Microbrowsers

34. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 34 Searching for Information on the Web Directory maintained by a search engine company Helps find information on the Web Search engine Subject directory The World Wide Web

35. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 35 The World Wide Web (Fig. 2-26) Multimedia on the Web Web pages incorporate graphics, animation, audio, video, and virtual reality Plug-ins

36. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 36 The World Wide Web Multimedia on the Web Graphics Used to enhance text-based Internet Graphics formats

37. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 37 Multimedia on the Web Graphics First media used to enhance the text-based Internet Graphics formats (JPEGs, or JPGs, and GIFs) Thumbnails (smaller versions for faster downloading time) The World Wide Web (Fig. 2-29)

38. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 38 Multimedia on the Web Animation Appearance of motion Series of still images Displayed in rapid sequence Marquees (animated text scrolling across screen) Animated GIFs (several images combined into a single GIF file) The World Wide Web

39. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 39 Audio on the Web Audio formats MP3, WAV,WMA, RealAudio, QuickTime Players include Windows Media RealPlayer iTunes Streaming audio (allows one to listen to a sound file as it downloads) The World Wide Web

40. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 40 Multimedia on the Web Streaming audio & video Allows longer listening and viewing Plays as it downloads Players include Windows Media Player RealPlayer Apple QuickTime (video) iTunes (audio) The World Wide Web

41. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 41 The World Wide Web Multimedia on the Web Virtual Reality Simulation of real or imagined environment that appears as a three-dimensional (3-D) space VR worlds: 3-D Web sites created with special VR software Require free VR plug-in to view Ex: “Walking tour” of a home

42. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 42 Other Internet Services E-mail Primary communication method for both personal and business use One of the original services on the Internet Allows one to create, send, receive, forward, store, print or delete messages E-mail programs Mailbox Mail server E-mail address User name @ Domain name

43. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 43 FTP (file transfer protocol) FTP server allows file downloads & uploads FTP site contains text, graphics, audio, video & program files Anonymous FTP is for anyone to use An FTP program is required to FTP Other Internet Services

44. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 44 Other Internet Services Newsgroups Online area in which users conduct written discussions about a particular subject Usenet (collection of all Internet newsgroups) News server (computer storing newsgroup msgs) Newsreader (program used to access newsgroup) Article (a previously entered message) Posting (adding an article to the newsgroup) Threaded discussion (initial and related articles) Message board (discussion board; easier to use) Blog (short for Web log; regularly updated journal)

45. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 45 Other Internet Services

46. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 46 Other Internet Services Mailing Lists Group of e-mail names and addresses given a single name Subscribe - Adding name to newsgroup/mailing list Unsubscribe – Removing name from the list LISTSERVs – Popular software programs that manage mailing lists (esp. educational lists) Newsgroup versus mailing list Newsgroup uses a newsreader for discussions Mailing list uses email for discussions

47. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 47 Chat Rooms Real-time typed conversation via computers Chat rooms (the channel or medium) Chat clients (program used to connect to a chat server) Normally included on a browser Freely downloaded from the Web Some are text-only; others support voice & video Other Internet Services

48. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 48 Other Internet Services Instant Messaging (IM) Notifies you when one or more people are online Allows exchange of messages and files Allows you to join a private chat room

49. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 49 Other Internet Services Role-Playing Games (RPGs) Popular with middle and high school students Tied to themes or topics of common interest Massively Multiplayer Online Role-Playing Games (MMORGs) Wide range of topics Includes people from all over the world Facebooks (allow one to set up his/her profile) Podcasting (automatically publishes sound or video files using Really Simple Syndication, or RSS, protocol)

50. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 50 Other Internet Services Internet telephony Also called “Voice over IP” or VOIP

51. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 51 Netiquette (Fig. 2-39) Internet etiquette Code of acceptable behaviors for Internet user Examples Avoid “flames” (abusive or insulting messages) Be brief and polite Watch spelling/grammar Avoid spam (unsolicited messages to many) Avoid sarcastic, offensive language or humor Use emoticans to express emotion ? :\ ? ? :o

52. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 52 Internet Security Firewalls (hardware & software to restrict access to data on a network by unauthorized personnel) Filtering software (allows parents and teachers to block access to certain material on the Internet) Acceptable Use Policy (AUP) An outline of user standards Reminds teachers, students and parents that they are guests on the Internet and they need to use it appropriately

53. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 53 The Impact of the Internet and the World Wide Web on Education The Web is the Gutenberg printing press of modern times Collaboration with other teachers and students ePALS – a classroom world-wide email cultural exchange program New instructional strategies are growing incredibly due to the Internet and the WWW.

54. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 54 The Future of the Internet and the World Wide Web In the next few years, the Internet will connect most of the world’s computers By 2007, 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 All K-12 teachers will have access to high-speed Internet in their classrooms Wireless networks, wireless notebook computers, wireless mobile labs, wireless Tablet PCs, and other wireless devices will become commonplace in K-12 education Everyday home and office appliances and other devices that use embedded computers, such as automobiles, will have built-in Internet access capabilities.

55. Chapter 2: Communications, Networks, the Internet, and the World Wide Web 55 The Future of the Internet and the World Wide Web Web search capabilities will be more intelligent and focused Within a few years, the Web will operate at speeds 10,000 times faster than today Businesses will continue to be the driving force behind the Web’s expansion Increased access speeds and greater availability will allow teachers and students to view thousands of full-motion videos over the Web The Web will become an integral part of all education and will revolutionize the way students learn core subjects

56. Communications, Networks, the Internet, and the World Wide Web Chapter 2 Complete