1 / 59

Introduction

Introduction. The Internet Defined Internet History The Way the Internet Works Internet Congestion Internet Culture Business Culture and the Internet Collaborative Computing and the Internet. The Internet Defined. Introduction The Information Superhighway

garren
Télécharger la présentation

Introduction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction The Internet Defined Internet History The Way the Internet Works Internet Congestion Internet Culture Business Culture and the Internet Collaborative Computing and the Internet From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  2. The Internet Defined Introduction The Information Superhighway Interesting Internet Facts From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  3. Federal Networking Council (FNC) Global information system Logically linked IP addresses Supports communications using TCP/IP Provides services publicly and privately The Internet Defined Introduction From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  4. Freeways/Cars • Learning to drive (easy) • Learning highways, etc. • Routine maintenance/repairs • Performing complex repairs Internet • Learning to surf (easy) • Learning to navigate • Building Web pages • Developing Web-related software/tools The Internet Defined The Information Superhighway • Analogous to freeways and cars From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  5. The Internet Defined Interesting Internet Facts • 25,000 new users daily • 325 million users (October 2000) • 343.25 million users projected (October 2002) • 50% of users are female • 73 million hosts (October 2000) • 200+ countries connected • World Wide Web sites double every two months From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  6. Internet History • 1960s Telecommunications • Packet Switching vs. Circuit Switching • Advanced Research Projects Agency Network (ARPANET) • 1970s Telecommunications • Local Area Network (LAN) • 1980s Telecommunications • Transmission Control Protocol/Internet Protocol (TCP/IP) • 1990s Telecommunications • Gopher, World Wide Web, Mosaic, Netscape • Internet Growth From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  7. Internet History From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  8. Internet History 1960s Telecommunications Early 1960s • Packet switching 1969 • Advanced Research Project Agency Network (ARPANET) • Bolt, Beranek, and Newman, Inc. (BBN) • U.S. Department of Defense • Four nodes (hosts) From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  9. Internet History 1970s Telecommunications 1970s • Local area networks (LANs) • Open architecture 1972 • ARPANET nodes increased to 23 • Ray Tomlinson invented e-mail From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  10. Internet History 1970s Telecommunications 1976 • UNIX to UNIX CoPy (UUCP) developed 1979 • User Network (USENET) developed • Connection between Duke University and University of North Carolina at Chapel Hill • Newsgroups emerged From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  11. Internet History 1980s Telecommunications 1980 • Computer Science Network (CSNET) • U. S. university computer science departments 1981 • Because It’s Time Network (BITNET) • City University of New York and Yale University • Mailing lists From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  12. Internet History 1980s Telecommunications 1983 • TCP/IP required for all ARPANET hosts • No charge (open system) • Allowed Internet growth 1985 • National Science Foundation Network (NSFNET) • NSF’s 5 super-computing centers From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  13. Internet History 1980s Telecommunications 1988 • Internet Worm • Virus written by Robert Morris • Infected 10% of Internet hosts • Internet Relay Chat (IRC) • Jarkko Oikarinen From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  14. Internet History 1980s Telecommunications 1989 • NSF took over ARPANET By the end of the 1980s • Domain Name System (DNS) • 100,000+ Internet hosts From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  15. Internet History 1990s Telecommunications • Commercial organizations on-line • URLs appeared in advertisements • Graphical browsing tools developed • HTML allowed users everywhere to publish on the World Wide Web From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  16. Internet History 1990s Telecommunications 1991 • Gopher • University of Minnesota • World Wide Web (WWW) • Tim Berners-Lee at CERN 1992 • WWW publicly available From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  17. Internet History 1990s Telecommunications 1993 • Mosaic released • Graphical browser for Web • Marc Andreessen at University of Illinois • “Each person who used it, loved it and told five friends.” From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  18. Internet History 1990s Telecommunications 1994 • Netscape Navigator released • Netscape Communications • Marc Andreessen and Jim Clark • Yahoo! • David Filo and Jerry Yang (Stanford University) From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  19. Internet History 1990s Telecommunications 1995 • Java • Sun Microsystems, Inc. • Microsoft Internet Explorer • Internet courses in colleges 1998 • Netscape Navigator source code released From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  20. Internet History Internet Growth • 100% each year • 16+ million computers linked • Reasons for success: • Decisions not politically based • Internet is distributed operation • Homogeneity of language and outlook • Inherently interesting to people • Free (or inexpensive) software From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  21. The Way the Internet Works • Network Benefits • Interconnected Networks and Communication • Physical Components • Network Connections • Client-Server Model • IP Addresses • Internet Protocol Version 6 (IPv6) • Web Page Retrieval From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  22. The Way the Internet Works Network Benefits • Convenience • Resource sharing • Facilitates communication • Monetary savings • Reliable • Scalable From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  23. The Way the Internet Works Interconnected Networks and Communication • TCP/IP (Transmission Control Protocol/Internet Protocol) • How computers connect, send, and receive information • TCP permits communication between computers • IP specifies how data is routed to and from computers From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  24. The Way the Internet Works Interconnected Networks and Communication • Example 1: Sending an e-mail message • Formatted according to Simple Mail Transfer Protocol (SMTP) • Example 2: Requesting a Web page • Formatted according to Hyper Text Transfer Protocol (HTTP) From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  25. The Way the Internet Works Interconnected Networks and Communication • Message split into IP packets: • Pieces of message • Information about sender • Information about receiver • Sequence number • Error checking information From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  26. The Way the Internet Works Interconnected Networks and Communication • Destination (receiving) computer: • Reassembles message • Sends request for corrupt packets to be resent • Advantages of packets: • Error recovery • Load distribution • Flexibility From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  27. The Way the Internet Works From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  28. The Way the Internet Works Physical Components • Servers • Answer service requests • Routers • Direct data packets • Networks • Transport packets • Copper wires, fiber-optic cables, radio waves, microwaves, infrared light, and visible light From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  29. The Way the Internet Works Network Connections • Two modems • One, used to connect to Internet • Another, used by Internet Service Provider (ISP) • Maximum connection speed usually 56 Kbps • Converts analog to digital • Network Interface Cards • Connect PCs in LANs From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  30. The Way the Internet Works Network Connections • Integrated Services Digital Network (ISDN) • Regular telephone lines and special adapters • Five times faster than traditional modems • Cable television connection • Teledesic (Bill Gates and Craig MacCraw) • Low-earth-orbit satellites From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  31. The Way the Internet Works Network Connections • Network Service Provider (NSP) • Local ISPs connect to NSPs • Leased-lines from local telephone companies • Transmit data at 1.54 megabits (Mbps) • IBM Avantis, AT&T, MCI, Sprint From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  32. The Way the Internet Works From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  33. The Way the Internet Works Client-Server Model • Generalization of interaction between clients and servers • Client makes request • Server responds From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  34. The Way the Internet Works From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  35. The Way the Internet Works IP Addresses • Unique numerical name identifying each computer on Internet • Vs. domain name • People-oriented unique name using symbols • 32 bits (four bytes) • Four natural numbers separated by dots (i.e., 132.177.4.124) • Network component and host component From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  36. The Way the Internet Works IP Addresses • Vital in packet switching • Network Information Center (NIC) • Assigns IP addresses • IP address to domain names • Resolver converts symbolic name to IP address • Programs convert IP addresses to symbolic names (vice versa) • nslookup (UNIX-based systems) From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  37. The Way the Internet Works IP Addresses • Point-to-Point Protocol (PPP) • Static IP address • Permanent • Connection through router • Dynamic IP address • Changes with each Internet connection • Connection through ISP From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  38. The Way the Internet Works Internet Protocol Version 6 • Major changes: • More addresses • IP address size from 32 bits to 128 bits • Simplified IP headers • Reduction of header fields in IP packet • Added security features From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  39. The Way the Internet Works Web Page Retrieval • Enter a URL (1)Browser determines “how” part of URL is HTTP (2)Browser queries the DNS for IP address (3)DNS responds with IP address (4) Browser establishes TCP connection to IP address (5) Browser sends a request for “what” portion of the URL From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  40. The Way the Internet Works Web Page Retrieval • Enter a URL (6) Server sends back the file requested (7) TCP connection closed (8) Browser renders text portion of HTML (9) Browser repeats steps for image files (10)Browser displays images as retrieved From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  41. Internet Congestion • World Wide Wait Problem • Technical Solutions • Issues and Predictions From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  42. Internet Congestion World Wide Wait Problem • Delays while using Internet • Reasons: • Increase in Internet users • Elaborate Web pages From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  43. Internet Congestion Technical Solutions • World Wide Web Consortium (W3C) issues: • Improving process of connecting • New techniques to expedite Web page requests • Refining how URL resolved • Web page design suggestions: • Avoid unnecessary graphics • Cascading Style Sheets (CSS) • PNG instead of GIF From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  44. Internet Congestion Issues and Predictions • Intranets • Isolated, private network with an internal Web • Cost • Inexpensive • Is it time to charge more for use of the Internet? From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  45. Internet Culture • Critical Evaluation of Information • Freedom of Expression • Communication Mechanisms • Advertising • Societal Impact From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  46. Internet Culture Critical Evaluation of Information • Who wrote the information? • Is the writing quality high? • Is the document up to date? • Are there obvious errors in the content? From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  47. Internet Culture Freedom of Expression • Lack of regulation • Blue ribbon • Obscene or offensive material • Censorship • Platform for Internet Content Selection (PICS) From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  48. Internet Culture Communication Mechanisms • E-mail and mailing lists • Internet Relay Chat (IRC) • Newsgroups • Videoconferencing • Emoticons and shorthand • Flaming and SHOUTING From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  49. Internet Culture Advertising • Clickable images • Revolving advertisements Societal Impact • Jobs • Information and communication • Weather, news, stock prices, travel information From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

  50. Business Culture and the Internet • On-line Businesses • On-line Business Hurdles • Cookies • Business and Safety/Security on the Web • Legal Environment • U.S. Government’s Commitment to Electronic Commerce From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web

More Related