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Chapter 2 - The Internet This slide presentation is designed to be viewed as a Slide Show. If viewed as a Slide Show your will be able to observe the animation and you should have functional hyperlinks. When in the Slide Show view, click to advance the slide. If the presentation is working very slowly, you may want to save it to your computer and then run the show. I hope you find this presentation educational. Could you create a presentation like this? Chapter 2 The Internet THE INTERNET Worldwide group of connected networks that allow public access to information and services No single organization owns or controls Estimated 360 million users in 2000 One-half billion in 2003 More than one billion in 2005 Internet Uses Access information, new, research & educational material Send or receive messages (e-mail) One of the original services of the Internet Meet and converse with people around the world in discussion groups or chat rooms Electronic commerce; click to view video, be patient What are some services found on the Internet? Instant Messaging Internet Telephony Web Newsgroups Chat E-mail HISTORY OF THE INTERNET Started as a WAN network of four computers at the University of California at Los Angeles in 1969 This Pentagon project was called ARPANET Advanced Research Projects Agency (ARPA) – ARPANET Internet Goals: Allow scientists at different locations to share information Function if part of the network were disabled Cold War Terrorism The Internal Structure - INTERNET Backbone first provided by National Science Foundation (NSF) – NSFnet NSF had (and still has) advanced technology that it applies to the Internet A backbone = main communications lines that carry the bulk of Internet traffic; several supercomputers networked Internet Backbone Backbone now provided by variety of corporations Telephone, cable, satellite companies and the government Various organizations help advise and define standards for the Internet Internet2 is an experimental area for research & a test site for new Internet technologies intended to improve the performance of the Internet World Wide Web Consortium (W3C) Click to view Quick Time video How can you connect to the Internet? Slow-speed technology High-speed connection Dial-up access modem in your computer uses a standard telephone line to connect to the Internet Digital subscriber line (DSL), cable telephone Internet services (CATV), cable modem, fixed, wireless, and satellite modems Connection must be established each time you log on. Slow but inexpensive Connection is always on— whenever the computer is running Fast but costs more Other high-speed broadband services In the Bismarck area I am the most familiar with services in RED Cable Internet service DSL Fiber to the Premises (FTTP) Fixed wireless Cellular Radio Network Wi-Fi Satellite Internet Service Internet Service Providers & Online Services ISPs are businesses that provide access to the Internet for a fee Regional are local (Bismarck area) ISPs National ISPs serve the entire country (AT&T; Earthlink) Online service providers (OSP) offer services to members only (AOL & MSN) News; weather; financial data; games travel guides; etc. Wireless service providers (WSP) Handheld devices; cell phones, pagers, notebook computers, automobiles, etc. How Data Travels the Internet Client can access server Server/Host computers Manage network resources In 1984; 1,000 computer hosts In 2003; 150,000,000 hosts Modem or Network card converts and transmits data Message is broken into little Packets of data that are sent individually Routers smart switches that select the route that the packets will follow Protocol An agreed-upon format for transmitting data between two devices TCP-IP (transmission control protocol/Internet protocol) Backbone Internet IP Addresses IP (Internet protocol) address is the unique number of a device on the Internet Domain name is a text name that represents the IP address Domain name servers (DNS) Translate domain names into IP addresses TLD is a top-level domain abbreviation com, edu, gov, org, etc. THE WORLD WIDE WEB WWW – a service on the Internet that consists of a worldwide collection of electronic documents (Web pages) containing links Started in 1991 – Tim Berners-Lee Hyperlinks (links) – navigate the WWW Links are found on Web pages Several Web pages make up a Web site Web servers manage Web sites & communications Webmasters create Web pages The World Wide Web (continued) Web servers deliver (serve up) the Web pages that you request Web browser or browser software provides a user a friendly way to access and view Web pages Internet Explorer, Firefox, etc. Microsoft Internet Explorer Safari Firefox Google Chrome Opera The World Wide Web A home page is the first page that a Web site displays Web pages provide links to other related Web pages Surfing the Web Downloading is the process of receiving information (continued) • Some Web pages are designed specifically for microbrowsers Uniform Resource Locator (URL) A Web page has a unique address called a URL or Web address Protocol://domain name / path to a specific Web page or file Hypertext transfer protocol (http://) Rules that define how pages (data) transfers on the Web. What is downloading? The process of a computer receiving information Depending upon connection speed, downloading can take from a few seconds to several minutes Uploading ? p. 76 Spider (Webopedia) software reads Web pages & creates an index. Hit is a Web page link that is listed as a result of a search. (IP address is not listed in the hit, test question) What is a search engine? Program used to find Web sites and Web pages by entering words or phrases called search text p. 80 Also called a keyword What is a subject directory? Search tool with organized set of topics and subtopics Lets you find information by clicking links rather than entering keywords Automobile; Automobile Sales; Automobile Sales Imports; Automobile Sales Imports Honda…. What is a hit? Any Web site name that is listed as the result of a search Note: Page Name & Domain Name but no IP numbers! This is a frequently missed test question! p. 80 Fig. 2-12 Check Prices Microsoft Office 2007 Pro Compare Prices Retail Store vs. Academic Online Prices Retail Stores Academic Online Stores Best Buy = $500 Gradeware = $170 Office Depot = $330 (upgrade) Academic Superstore = $170 Sam’s Club = $271 (upgrade) Ultimate Steal = $59 What are the nine basic types of Web sites? Portal News Informational Business/Marketing Educational Entertainment Advocacy Blog – on line journal/diary Vlog – video log Personal Evaluating a Web Site Beware! Information presented on the Web must be evaluated for accuracy No one oversees the content of Web pages Multimedia on the Web Web pages incorporate color, sound, motion, and graphics with text Plug-ins – run multimedia elements Sound, video, graphics & animated graphics Added to and becomes part of the browser Extend the capabilities of the browser Java – multimedia language Applets Multimedia on the Web Multimedia refers to any application that combines text with: Multimedia on the Web (continued) Graphic file formats JPEG for pictures GIF for line art (clip art) Other graphic formats include BMP, PNG & TIFF Thumbnails – small versions of a larger image JPEG thumbnail GIF thumbnail Multimedia on the Web (continued) Animation is the appearance of motion Marquees – text scrolling across the screen Animated GIF combines several still images into a single file Animation = Next Slide Audio on the Web Common sound formats Streaming audio MP3 (compressed) & WAV Example of “Streaming” in a couple of slides. Listen as sound file is downloaded Internet telephony – Internet telephone service VoIP = Voice over IP (Internet Protocol) Audio on the Web RealAudio Listen (live) to radio & TV Try it! Select a station and then click PLAY Are your speakers on? Video on the Web Streaming video Check out the “Webcam” View as video file is downloaded Allows videoconferencing RealVideo – live video feeds A popular video file format Motion Picture Experts Group (MPEG) Be patient this may take a while to download. Streaming Audio & Video Sound ? Quick Time Plug-in required Consider downloading the free plug-in, you may be prompted when you click the image. http://www.apple.com/trailers/miramax/cold_mountain/t1_large.html Virtual Reality on the Web Simulation of real or imagined environment that appears as a three-dimensional (3-D) space Virtual reality modeling language (VRML) A site created with VRML is a VR (virtual) world Used for modeling 3d games Architects use to model buildings Scientists use to study molecules and other structures Virtual Tour Custer House, Ft Lincoln, Mandan, ND Click to take a virtual tour WEBCASTING Pull technology – client requests the Web page from the Web server Push technology - Web files are downloaded automatically from Web servers to the client At a periodic interval The user does not need to request the information ELECTRONIC COMMERCE Conducting business activities online Businesses have Electronic money (e-money) Encryption Scrambled data sent over the WWW Used for secured transactions E-Commerce Click the image to view a video WEB PUBLISHING Web pages are created with the Hypertext markup language (HTML) - tags Web authoring software HTML editors make programming more user friendly Microsoft Expression Web Dreamweaver and HomeSite Word processing packages To publish a Web site the Web pages must be uploaded to a Web server OTHER INTERNET SERVICES E-mail An original service of the Internet Primary communication method for both personal and business use E-mail users have e-mail addresses Electronic messages are stored in mailboxes residing in mail servers Outlook, Netscape, Eudora & many others E-mail Addresses An e-mail address consists of Post Office Protocol (POP3) is used to retrieve e-mail from a mail server Username & domain name The set of rules for e-mail transfer The technology used by many mail servers Attachments (graphics, video clips, & files) can be sent with e-mail messages Encoding converts attachment to a binary form and back What is a PDF file? How do you edit a PDF file? FTP INTERNET SERVICES FTP (file transfer protocol) is an Internet standard that permits files to be uploaded and downloaded on the Internet Web pages to Web servers to clients. Many operating systems include FTP capabilities FTP servers contain files that can be transferred Anonymous FTP – anyone can transfer the files Search for: FTP Site PDF to Word (free?) (Convert a PDF document into a Word document & then edit) Telnet INTERNET SERVICES Telnet Log into remote computers & have the remote computer work for the user Access remote databases, directories, and library catalogs Today’s use of Internet Service Providers and Web browsers has reduced the need for Telenet Most libraries have converted to a Web based system OTHER INTERNET SERVICES Newsgroups An online discussion about a particular subject You may discuss sports or a breaking news story Collection of newsgroups is called a Usenet Mailing Lists & LISTSERVs Send mail to a large group of people at one time LISTSERV is a popular mailing list software product What is a chat? Real-time typed conversation that takes place on a computer Chat room is location on a server that permits users to discuss topics of interest Instant messaging notifies you when someone you know is online & then you can exchange messages with them p. 98 Fig. 2-32 NETIQUETTE Internet etiquette The code of acceptable behavior users should follow while on the Internet Avoid “spam” – sending messages to several people Respect Chat room Lawsuit Benedictine value = Respect for others Chapter 2 Complete