This document provides an overview of the Internet and its applications. It discusses various topics including Internet architectures (Internet, intranet, extranet), communication applications (email, messaging, e-commerce, voice over IP), virtual private networks, WAN technologies, and audio/video streaming and conferencing.

1. CHAPTER An Overview of Internet and Its Applications

2. Chapter Objectives Define the different architectures of the Internet Highlight some of the communication applications on the Internet

3. Chapter Modules Internet, Intranet and Extranet Messaging E-Commerce Voice Over IP and Internet Telephony

4. Chapter Modules ( Continued) Virtual Private Network (VPN) WAN and Access Technologies Audio and Video Streaming Video Conferencing

5. Web Research Audio and Video streaming www.calstatele.edu/ats/real www.microsoft.com Extranet e-server in a box Internet appliance VPN www.cisco.com www.lucent.com Overcoming latency in TCP/IP

6. MODULE Internet Architectures

7. Architectures Internet The global Intranet An Internet restricted to the company’s own perimeter Extranet Intranet extended to include outside organizations dealing with a particular organization

8. Internet Defined Internet Backbone run by major carriers Individuals SOHO User Company Network Internet Service Provider (ISP) Internet Service Provider (ISP)

9. Intranet Defined Internal Company Backbone Departmental LAN Fire Wall Mini or Mainframe Computer systems Departmental Computer System Internet

10. Extranet Defined Internet Company’s Intranet Business Associates Other businesses dealing with company A. Virtual Private Network (VPN)

11. END OF MODULE

12. MODULE Email and Messaging

13. Email Messages exchanged among Internet subscribers Vary from a simple text based messages to one that carries different attachments Word, PowerPoint documents Any computer file Video and audio clippings etc.

14. Messaging Email expanded to include a number of other functions and services Document sharing and collaboration Whiteboard applications Scheduling of group activities Etc.

15. Collaboration and Sharing Internet User 1 User 2 Document for Sharing or Collaboration Sharing: Both users can see the document but only one can make changes Collaboration: Both users can see and also make changes to the document NetMeeting

16. Implementation Of Messaging Lotus Domino server, Microsoft Exchange Server Server Client 1 Client 2 Internet Internet service Provider WWW Services

17. Major Messaging Products Microsoft Exchange Server Outlook and Outlook Express Clients Lotus Domino Server cc:Mail Lotus Notes (Client) Netscape ???

18. END OF MODULE

19. MODULE E-Commerce

20. Web Research e-server in a box IBM’s web site

21. END OF MODULE

22. MODULE Voice Over IP and Internet Telephony

23. Voice Over IP and Internet Telephony Defined The use of the internet to transmit voice in real-time Transmission of digitized voice using the Internet Protocol Internet Telephony is an example Usage of the Internet to transmit telephone calls

24. Internet Telephony Defined Using the Internet (TCP/IP) for largely the telephone related applications Termination of voice traffic

25. Voice over IP Prospects and Challenges Voice transmission over the Internet has been identified as one of the largest growth areas Companies will in the future use the Internet extensively for voice communications Current IP is not well suited for voice transmission Latency being the biggest drawback Bandwidth restrictions also hamper voice transmission IP is being improved to carry voice

26. Internet Telephony A growing market Further information http://www.internettelephony.com/ Current Products (???) Net meeting (Microsoft) ICQ Cooltalk (Netscape) etc. Long-term focus is on regularly using the Internet as a viable alternative to the Plain Old Telephone Service (POTS) H.323 is the prominent standard for Internet telephony

27. Sample Telephony Applications Source: Vocaltech Computer-to-Computer Calling Computer-to-Phone Calling: Requires ITSP service in addition to regular ISP service www.dialpad.com Phone-to-phone Using TCP/IP Live Motion Video Video Conferencing Whiteboarding: Share and edit photos, documents and drawings with others in real time. Voice Mail: Record compressed voice files and sending them as attachments.

28. END OF MODULE

29. MODULE Virtual Private Networks (VPN)

30. VPN Defined A private network that uses the public network infrastructure A secured web of tunnels that links various nodes to form the Virtual Private Network

31. Virtual Private Network Public VPN

32. VPN Implementation Internet Company’s Intranet Point-to-Point Tunneling Protocol (PPTP) Fire Wall

33. VPN Past and Present Past Based on PSTN (Public Switched Telephone Network) Present Based on next generation public network technologies Source: VPNWorx , VPN Quick Reference Guide

34. Base Technologies for VPN Carrier IP PPTP Frame Relay ATM

35. Areas of Applications All major business organizations that require a secured Extranet

36. END OF MODULE

37. MODULE WAN and Access Technologies

38. WAN Scope Enterprise-wide Metropolitan and National Global Underlying network infrastructure for the Internet Fastest growing network Growth is appreciable in the area of Virtual Private Network

39. The Early Days of Communications and Computing Telecommunication Centered on analog technology Data communication needs Centered around digital technology Digital to analog interface For long distance communications

40. Long-distance Communications Modulation Digital Digital Plain Old Telephone Service (POTS) Analog Interface

41. Initial WANs Introduced to overcome the limitations of general purpose analog telephone lines used Better conditioned lines such as leased lines were used Driven by a collection of computers for routing the data traffic from source to destination Arpanet was the first WAN to be created X.25 was the initial communication technology used X.21 was used in Europe

42. Basic Components of the WAN Computers/ Routing algorithms X.25 Driven Leased lines Routing devices

43. Present Status of WANs Information is carried in digitized form in many segments of the WAN Digital communication lines Over copper wire Over fiber-optics Telecommunications and computer communications are merging in terms of deploying digital technology

44. WANs: Present and Future Move towards digital technology Technologies Frame Relay ATM Point-to-point digital communication will become widely used in the future The WAN of the future will be designed to meet with the increasing bandwidth demands of the Internet Internet2

45. Internet2: The WAN of the Future ATM operating at several hundred Mbps Ramp Business Computer System ATM Switches High speed digital lines

46. Possible Convergence Digital Technology Networks Local Enterprise Wide area Global Point-to-point ATM connection is possible probably under a single technology ATM

47. ATM Promise Server Client 1 Client 2 25 Mbps ISP 100 Mbps Internet Backbone 1 Gbps 300 Mbps

48. Challeng Posed by Gigabit Ethernet to ATM 1 Gbps (Gigabit) 100 Mbps (Fast) 10 Mbps 1 Mbps (Past) Ethernet Evolution Client 2 10 Mbps/ 100 Mbps/ 1 Gbps Server ISP Client 1 Hub

49. Wide Area Network Technologies WAN Technologies: X.25 (old) FDDI Frame Relay ATM Los Angeles Seattle New York Florida

50. Front-end Access Technologies ISDN xDSL Cable modem Direct satellite access ADSL is an example of xDSL

51. Access Speeds Fastest speed of an analog modem is around 56K bps Newer technologies operate at faster speeds Newer technologies have made a significant contribution in increasing the speed of communication

52. Digital Internet Technologies Summarized FDDI Frame Relay ATM Cable Modem Direct Satellite Access xDSL ISDN

53. END OF MODULE

54. MODULE Audio and Video Streaming

55. Audio and Video Streaming Deliver continuous audio and video streams over a low bandwidth connection Packet switching networks do no guarantee real-time and continuous delivery of data packets Streaming involves compression and decompression (CODEC)

56. Application Areas Dissemination of multimedia information on the web Training and education Etc.

57. Streaming Examples Streaming Software Audio (wav) Video (AVI) Real Format RM, RMA, RT, RP etc. Windows Format ASF etc. Raw File Streamed File

58. Hosting of Streamed Media Streaming Server (Real Server or Windows Media Server) Internet Streaming at 28.8, 56, 128 etc. Kbps

59. Method of Delivery Unicasting Multicasting Broadcasting

60. Major Streaming Technologies Real Microsoft Windows Media Technologies

61. END OF MODULE

62. MODULE Video Conferencing

63. Video Conferencing The exchanging of audio and video information while engaged in conferencing

64. Major Types of Video Conferencing Dedicated video conferencing Telecommunication lines are used solely for the purpose of setting up a video conferencing facility Desktop video conferencing Video conferencing conducted from a computer connected to the Internet

65. Video Conferencing Standard H.232 Series of standards

66. Sample Desktop Video Conferencing Products CU-SeeMee Intel ProShare Microsoft NetMeeting PictureTel

67. END OF MODULE

68. Keywords Intranet, Extranet, Internet VPN, PPTP Real Media and Windows Media Network appliance and Internet Appliance Sharing, Collaboration Messaging Server and Messaging Client

69. Keywords SMTP, POP3, IMAP VoIP, H.323, IPv6 X.25, ATM, Frame Relay, FDDI T1, T3, OC1, OC2 ISDN, xDSL, Cable Modem, Satellite Unicasting, Multicasting and Broadcasting

70. Microcomputer-based Distributed Architecture Fiber Optic Backbone (FDDI) Mainframe/ Minicomputer Systems Bus LAN Ring LAN WAN Gateway (TCP/IP) Modem Gateway External Digital/ Analog Lines

71. END OF MODULE

72. Microcomputers Widespread usage Serious business computer Dramatic increase in power Comparable to mainframes of the past Declining cost Affordable to use in all levels of business Communication device Access services and resources on the Internet

73. Connectivity Computers are increasingly being viewed as resources in a network and not simply as stand-alone units any more LANs, Departmental networks, Enterprise networks, WANs etc. are deployed widely in business

74. Downsizing: Path of Evolution Centralized Mainframe More power to the user Better management of shared data Reduced cost of ownership Distributed Network Client-Server Architecture Thin-client concept

75. Client-Server Computing Architecture Centralized data Control and management Distributed processing Processing using client-tools Mainframe advantage Microcomputer flexibility

76. Preview of Client-Server Computing Back-end data storage and retrieval. Front-end interface and data manipulation tools. Server Clients

77. A Preview of Thin-Client Concept Limited front-end processing and storage Extensive back-end data storage, retrieval and Processing Powerful Server Thin Clients

78. Digitization Of Telecom Network Mode (ATM)

79. Front-end Access Technologies ISDN xDSL Cable modem Direct satellite access ADSL is an example of xDSL

80. Access Speeds Fastest speed of an analog modem is around 56K bps Newer technologies operate at faster speeds In the Mbps region Newer technologies have made a significant contribution in increasing the speed of communication

81. Summary of Digital Technologies in Telecommunications FDDI Frame Relay ATM Cable Modem Direct Satellite Access xDSL ISDN

82. END OF MODULE

83. Internet Access Gain access to the resources on the WWW. Software: Web Browser Micro Modem Serial Port Internet Access provider ISP

84. General Access Software: ProComm Plus, Hyper Terminal Public Switched Network (PSN) Gain access to a company’s mainframe to run Unix applications Micro Modem Serial Port

85. Telecommuting Main Office PSN Satellite Office Home ProComm PLUS ProComm PLUS

86. Typical LAN Client OS/ Windows 9x Client 1 Client 2 Client 3 Server: Network OS, Applications, Data etc. Windows NT server Operating System

87. EDI Defined Vendor (Supplier) Automate the Purchase/ Supply process Retail (Purchaser)

88. EDI Example Vendor Retailer Electronic procurement with minimum human intervention Purchase Order Invoice etc.

89. Distributed Data Processing Data/server Data/server Query Data/server Oracle Distributed DBMS

90. Transparency in the Search Process Data/server Data/server Query Data/server Oracle Distributed DBMS 1 3 2

91. END OF MODULE END OF CHAPTER

92. END OF MODULE END OF CHAPTER