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The Internet

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The Internet

  1. 1. <ul><li>Using the Internet: </li></ul><ul><li>Making the Most of the Web’s Resources </li></ul>
  2. 2. Topics <ul><li>Internet communications </li></ul><ul><li>Online annoyances </li></ul><ul><li>How the Internet works </li></ul><ul><li>Internet Basics </li></ul><ul><li>Origin of the Internet </li></ul><ul><li>Future of the Internet </li></ul>
  3. 3. Communications through the Net <ul><li>VOIP </li></ul><ul><li>Wikis </li></ul><ul><li>Newsgroups </li></ul><ul><li>Email </li></ul><ul><li>Mailing lists </li></ul><ul><li>Social networking </li></ul><ul><li>E-commerce </li></ul>
  4. 4. Voice over Internet Protocol <ul><li>VoIP - The Internet as a means to place phone calls </li></ul><ul><li>Uses technology similar to e-mail to send voice data digitally </li></ul><ul><li>Requires </li></ul><ul><ul><li>a microphone </li></ul></ul><ul><ul><li>an Internet connection </li></ul></ul><ul><ul><li>A VoIP provider </li></ul></ul><ul><li>Services differ </li></ul><ul><ul><li>Free services require an account on both ends </li></ul></ul><ul><ul><li>Paid services connect phone to computer </li></ul></ul><ul><ul><li>Cable and DSL providers offer phone through broadband </li></ul></ul><ul><ul><li>WiFi IP phones call through Internet hotspots and wireless networks </li></ul></ul>
  5. 5. Wikis <ul><li>A wiki is a Web site that allows anyone to change its content </li></ul><ul><li>Wikis provide an excellent source for collaborative writing </li></ul><ul><li>Unlike blogs, wikis can be edited for a “common” opinion </li></ul><ul><li>Edits can be anonymous or named </li></ul><ul><li>Be careful of bias in entries </li></ul><ul><li>“ wiki” is a Hawaiian word for “fast” </li></ul><ul><li>First site with wiki in the name set up in 1995 </li></ul>
  6. 6. Newsgroups <ul><li>Usenet &quot;News&quot; formed in 1980 </li></ul><ul><li>Online discussion forums </li></ul><ul><li>Post and reply to messages publicly </li></ul><ul><li>Need a feed from a news server - most ISPs have one </li></ul>
  7. 7. E-mail <ul><li>fast, convenient, cheap </li></ul><ul><li>asynchronous </li></ul><ul><li>E-mail accounts </li></ul><ul><ul><li>Client-based </li></ul></ul><ul><ul><li>Web-based </li></ul></ul><ul><li>Forwarding </li></ul><ul><li>(image from Wikipedia &quot;How Email Works&quot;) </li></ul>
  8. 8. Mailing lists <ul><li>&quot;Listservs&quot; </li></ul><ul><li>people must subscribe </li></ul><ul><li>messages sent by email </li></ul><ul><li>sent only to people who subscribe, not general public </li></ul><ul><li>do NOT use the &quot;Reply All&quot; option unless you mean to! </li></ul>
  9. 9. Social Networking <ul><li>MySpace, FaceBook </li></ul><ul><li>easy, cheap </li></ul><ul><li>danger of identity theft </li></ul><ul><li>danger of revealing information which can be harmful later </li></ul><ul><li>danger of sexual predators </li></ul>
  10. 10. E-commerce <ul><li>buying, selling, advertising, banking </li></ul><ul><li>look for secure &quot;signed&quot; sites </li></ul><ul><li>https:// versus http:// </li></ul><ul><li>check with Better Business before buying </li></ul><ul><li>use credit card for purchase </li></ul>
  11. 11. Online Annoyances <ul><li>Spam – electronic junk mail </li></ul><ul><li>Pop-ups – intrusive advertising </li></ul><ul><li>Cookies – tracking user’s browsing habits </li></ul><ul><li>Malware - software that has a malicious intent - spyware, viruses, Trojans, worms, etc. </li></ul><ul><li>Phishing and Hoaxes – Ruses to fool and maybe steal from users </li></ul>
  12. 12. Spam <ul><li>Junk e-Mail </li></ul><ul><li>May soon comprise 90% </li></ul><ul><li> of email volume </li></ul><ul><li>Named after a Monty Python sketch Link </li></ul><ul><li>Antispam practices </li></ul><ul><ul><li>Don’t reply to it, even to “unsubscribe”! </li></ul></ul><ul><ul><li>Use “dummy” addresses – can get free ones </li></ul></ul><ul><ul><li>Read privacy statement on a site before you give them your address </li></ul></ul><ul><ul><li>Spam filters </li></ul></ul>
  13. 13. Pop-ups <ul><li>Usually advertising </li></ul><ul><li>Pop-up automatically </li></ul><ul><li>Can also contain spyware </li></ul><ul><li>Most browsers can prevent them </li></ul><ul><li>Pop-up blockers </li></ul>
  14. 14. Cookies <ul><li>Text files stored on client computers when visiting Web sites </li></ul><ul><li>Used on return visits to Web sites </li></ul><ul><li>Unique ID number </li></ul><ul><li>Personal information remembered </li></ul><ul><li>Privacy risk </li></ul><ul><ul><li>Selling information </li></ul></ul>
  15. 15. Spyware <ul><li>Added as a program piggybacked with a requested program </li></ul><ul><li>Secretly gathers information, usually about surfing habits </li></ul><ul><li>Antivirus software doesn’t detect it </li></ul><ul><li>Spyware removal programs are required </li></ul>
  16. 16. Spyware <ul><li>Very often comes in from file-sharing, P2P sites </li></ul><ul><li>Ties up system resources, can modify browser settings, can spawn popups and other ads </li></ul><ul><li>Read the EULA for any software you install before you install! </li></ul><ul><li>Run Ad-Aware to clean it up </li></ul>
  17. 17. Phishing and Hoaxes <ul><li>Phishing is a phony communication from a trusted source </li></ul><ul><li>Phishing attempts to scam someone into sending vital information </li></ul><ul><li>Hoaxes are attempts to scam people into sending money, or join a chain letter </li></ul>
  18. 18. Malware <ul><li>Software that has a malicious intent </li></ul><ul><li>Spyware is a form of malware </li></ul><ul><li>Other forms are viruses, worms, and Trojan horses </li></ul><ul><li>Designed to render a computer useless or control it completely </li></ul>
  19. 19. How the Internet works <ul><li>Domain Names </li></ul><ul><li>URLs </li></ul><ul><li>Navigating the Web </li></ul>
  20. 20. Domain Names <ul><li>Easy-to-remember names for Internet servers </li></ul><ul><ul><li>Ends with an extension that indicates its top-level domain </li></ul></ul><ul><li>Every domain name corresponds to a unique IP address </li></ul><ul><ul><li>Domain Name System </li></ul></ul><ul><ul><li>cybersquatting </li></ul></ul><ul><li>ICANN coordinates technical management of the Internet’s Domain Name System </li></ul>
  21. 21. Domain Names <ul><li>Most specific information on the LEFT </li></ul><ul><li>Top Level Domain Names </li></ul><ul><ul><li>.gov .com .edu .net </li></ul></ul><ul><li>Subnets and Sub Domains </li></ul><ul><ul><li>uky.edu </li></ul></ul><ul><ul><li>cs.uky.edu </li></ul></ul><ul><ul><li>www.cs.uky.edu </li></ul></ul><ul><ul><li>ftp.cs.uky.edu </li></ul></ul>
  22. 22. Current Top-Level Domains <ul><li>. aero Members of the air transport industry </li></ul><ul><li>.biz Businesses </li></ul><ul><li>.com Can be used by anyone </li></ul><ul><li>.coop Cooperative associations </li></ul><ul><li>.edu Degree granting institutions </li></ul><ul><li>.gov United States government </li></ul><ul><li>.info Information service providers </li></ul><ul><li>.mil United States military </li></ul><ul><li>. museum Museums </li></ul><ul><li>. name Individuals </li></ul><ul><li>.net Networking organizations </li></ul><ul><li>.org Organizations (often nonprofits) </li></ul><ul><li>.pro Credentialed professionals </li></ul>
  23. 23. Top Level Domains - Country Codes
  24. 24. URL <ul><li>Uniform Resource Locator </li></ul><ul><ul><li>Unique Internet address </li></ul></ul><ul><ul><ul><li>Protocol could be http, mailto, ftp, news, … </li></ul></ul></ul><ul><ul><ul><li>NOTE difference between http and https </li></ul></ul></ul>URL http:// Protocol identifies the means of access www.nytimes.com/ Domain name contains the host and top-level domain Pages/cartoons/ Path identifies the subdirectories within the Web site
  25. 25. Navigating the Web: Web Browsers <ul><li>Software running locally on your machine </li></ul><ul><li>Graphical </li></ul><ul><li>Enables Web navigation </li></ul><ul><li>Popular browsers: </li></ul><ul><ul><li>Internet Explorer </li></ul></ul><ul><ul><li>Firefox </li></ul></ul><ul><ul><li>Camino (Mac OSX) </li></ul></ul>
  26. 26. Web Sites <ul><li>Web site: </li></ul><ul><ul><li>Collection of related Web pages </li></ul></ul><ul><ul><li>First page known as Home or Index page </li></ul></ul><ul><li>Web pages: </li></ul><ul><ul><li>HTML documents </li></ul></ul><ul><ul><li>Hyperlinks </li></ul></ul>Related pages
  27. 27. The Internet and Copyright <ul><li>All original material on the Net is copyrighted, © or not </li></ul><ul><li>Copyright is violated when you get economic benefit from using the material </li></ul><ul><ul><li>Exception of &quot;academic fair use&quot; </li></ul></ul><ul><li>Plagiarism is different from copyright violation – it is presenting someone else's work as your own </li></ul><ul><ul><li>Credit your sources! </li></ul></ul>
  28. 28. Search Engines <ul><li>“ Spider” or “Web Crawler” program scans Web pages </li></ul><ul><li>Information found is entered in their database </li></ul><ul><li>User enters keyword or phrase in search box in browser </li></ul><ul><li>Results (hits) are sent to the client software and displayed </li></ul>
  29. 29. Evaluating Web Sites <ul><li>Who is the author of the article or Web site sponsor? </li></ul><ul><li>What audience is the site geared toward? </li></ul><ul><li>Is the site biased? </li></ul><ul><li>Is the information current? </li></ul><ul><li>Are links available? </li></ul><ul><li>Who is hosting? Is it a .gov site? .edu? .com? </li></ul>
  30. 30. File-sharing - P2P networks <ul><li>Files traded from machine to machine - broadband </li></ul><ul><li>Majority of files are copyrighted and permission has not been given for the copying </li></ul><ul><li>Risks </li></ul><ul><ul><li>Legal problems </li></ul></ul><ul><ul><li>Malware in both the software and the files </li></ul></ul>
  31. 31. Software Copyrights and Licenses <ul><li>Different types of software licenses - where the money come from? </li></ul><ul><ul><li>Commercial software -from sale of licenses </li></ul></ul><ul><ul><li>Shareware - from registrations and ads </li></ul></ul><ul><ul><li>Freeware - from advertising and spyware </li></ul></ul><ul><ul><li>Open source - free labor of volunteers and donations </li></ul></ul><ul><ul><li>Public domain - donations from community </li></ul></ul>
  32. 32. The Internet: The Basics <ul><li>Protocols </li></ul><ul><li>IP numbers </li></ul><ul><li>Clients and servers </li></ul><ul><li>Connecting to the Internet </li></ul><ul><li>Origin of the Internet </li></ul><ul><li>The Internet vs. the Web </li></ul>
  33. 33. Internet Protocols <ul><li>TCP and IP serve as the primary protocols responsible for message transmission on the Internet </li></ul>
  34. 34. Internet Protocol <ul><li>Messages are divided into small pieces called packets </li></ul><ul><li>These are labeled with the IP numbers of the machine they came from and the one they are going to, and a order number ( like 1 of 5) </li></ul><ul><li>The protocol says how to route them to get to the destination </li></ul><ul><li>Not all packets take the same route! </li></ul>
  35. 35. IP Addresses <ul><li>IP addresses are addresses that identify computers on the Internet </li></ul><ul><ul><li>Static IP address </li></ul></ul><ul><ul><li>Dynamic IP address </li></ul></ul>
  36. 36. IP Addresses <ul><li>IP addresses have the problem in TCP/IP of running out </li></ul><ul><li>Internet 2 consortium designing new protocols that fix the problem </li></ul><ul><li>Dynamic IP numbers – short term fix </li></ul>
  37. 37. Client and Server <ul><li>Client computer: </li></ul><ul><ul><li>Users connect to the Internet </li></ul></ul><ul><ul><li>Request data and Web pages </li></ul></ul><ul><li>Server computers: </li></ul><ul><ul><li>Store Web pages and data </li></ul></ul><ul><ul><li>Return the requested data to the client </li></ul></ul>Server Client
  38. 38. Connecting to the Internet <ul><li>Dial-up connection: </li></ul><ul><ul><li>Uses standard telephone line </li></ul></ul><ul><ul><li>Least costly connection </li></ul></ul><ul><ul><li>Requires a modem </li></ul></ul><ul><ul><ul><li>Converts analog to digital and vice versa </li></ul></ul></ul><ul><ul><li>Slowest connection speed (56Kbps) </li></ul></ul>
  39. 39. Broadband Connections <ul><li>Digital Subscriber Lines </li></ul><ul><ul><li>Faster than dial-up </li></ul></ul><ul><ul><ul><li>Upload (300Kbps – 1.5Mbps) </li></ul></ul></ul><ul><ul><ul><li>Download (1Mbps – 1.5Mbps) </li></ul></ul></ul><ul><ul><li>Requires special DSL modem </li></ul></ul><ul><ul><li>Symmetrical or Asymmetrical </li></ul></ul>DSL modem
  40. 40. Broadband Connections <ul><li>Cable: </li></ul><ul><ul><li>Uses TV coaxial cable </li></ul></ul><ul><ul><li>Fast connection speed (500Kbps – 4Mbps) </li></ul></ul><ul><ul><li>Speed depends on number of users </li></ul></ul><ul><ul><li>Not available in all areas </li></ul></ul><ul><ul><li>Requires a cable modem </li></ul></ul>Coaxial cable
  41. 41. Satellite Connections <ul><li>Uses a satellite dish and coaxial cable </li></ul><ul><ul><li>Download speed 500 kbps </li></ul></ul><ul><ul><li>Upload speed 100 kbps </li></ul></ul><ul><ul><li>Signal is affected by location and weather </li></ul></ul>
  42. 42. Comparing Internet Connection Options 500 Kbps 100 Kbps Satellite 4 Mbps 500 Kbps Cable 1.5 Mbps 1.5 Mbps DSL (SDSL) 1 Mbps 300 Kbps DSL (ADSL) 56 Kbps 56 Kbps Dial-Up Maximum Download Data Transfer Rate (approximate) Maximum Upload Data Transfer Rate (approximate) Connection Option
  43. 43. Choosing an ISP <ul><li>Factors to consider: </li></ul><ul><ul><li>Cost </li></ul></ul><ul><ul><li>Local access numbers </li></ul></ul><ul><ul><li>Services Offered – email, web page hosting, news reading </li></ul></ul><ul><ul><li>Reliability </li></ul></ul><ul><ul><li>Speed </li></ul></ul><ul><ul><li>Support and Customer Service </li></ul></ul>
  44. 44. ISP Infrastructure
  45. 45. The Origin of the Internet <ul><li>ARPANET: </li></ul><ul><ul><li>Advanced Research Projects Agency Network </li></ul></ul><ul><ul><li>Funded by the U.S. government in the 1960s, lasts until 90's </li></ul></ul><ul><ul><li>Allowed computers at leading universities and research organizations to communicate with each other over great distances </li></ul></ul><ul><ul><li>First Working Version of the Packet Switching Network </li></ul></ul>
  46. 47. NSFNet – National Science Foundation Network <ul><li>Connecting 5 supercomputers and the researchers using them, 1986 </li></ul><ul><li>commercialization of the Internet - late 80's </li></ul><ul><li>NSF stops funding the Net - 1994 </li></ul>
  47. 48. Internet Structure
  48. 49. The Web <ul><li>The Web is a part of the Internet distinguished by: </li></ul><ul><ul><li>common communication protocols TCP/IP and HTML </li></ul></ul><ul><ul><li>special links (called hyperlinks ) </li></ul></ul><ul><li>Web invented in 1989 by Tim Berners-Lee </li></ul><ul><li>1993, National Center for Supercomputing Applications (NSF) releases the Mosaic browser </li></ul><ul><li>Developers of Mosaic release Netscape (1994) </li></ul>
  49. 50. The Internet vs. The Web <ul><li>Internet – part of the system that is primarily hardware infrastructure (telecommunications, routers, servers, disk drives, etcetera) </li></ul><ul><li>Web – part of the system that contains intellectual property in many formats (text files, graphic files, sound files, video files, etc.) </li></ul><ul><li>The Internet existed before the WWW interface – people used command line programs </li></ul>
  50. 51. Future of the Internet <ul><li>Large Scale Networking (LSN): </li></ul><ul><ul><li>Research and development of cutting-edge networking and wireless technologies </li></ul></ul><ul><li>Internet2: </li></ul><ul><ul><li>Project sponsored by universities, government, and industry to develop new Internet technologies </li></ul></ul><ul><ul><li>Internet2 backbone supports transmission speeds of 9.6 Gbps </li></ul></ul>
  51. 52. Internet Access Security <ul><li>&quot;always on&quot; is security risk - turn the computer off! </li></ul><ul><li>keep OS and anti-virus software up to date </li></ul><ul><li>USE firewall software </li></ul><ul><li>browser security settings </li></ul><ul><li>for LAN, use NAT - router Network Address Translation </li></ul><ul><li>virtual private network (VPN) </li></ul>
  52. 53. Issue: Free Wi-Fi access <ul><li>Some people offer wireless access for free to the community </li></ul><ul><li>A good point - people who can't afford to pay for it can use it </li></ul><ul><li>Broadband providers don't like people giving it away for free </li></ul><ul><li>A bad point - can be used for illegal activities </li></ul>

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