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Chapter 6

Chapter 6. Telecommunications and Networks. Learning Objectives. Understand the concept of a network. Apply Metcalfe’s law in understanding the value of a network.

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Chapter 6

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  1. Chapter 6 Telecommunications and Networks

  2. Learning Objectives • Understand the concept of a network. • Apply Metcalfe’s law in understanding the value of a network. • Identify several major developments and trends in the industries, technologies, and business applications of telecommunications and Internet technologies. • Provide examples of the business value of Internet, intranet, and extranet applications.

  3. Learning Objectives • Identify the basic components, functions, and types of telecommunications networks used in business. • Explain the functions of major components of telecommunications network hardware, software, media, and services. • Explain the concept of client/server networking. • Understand the two forms of peer-to-peer networking. • Explain the difference between digital and analog signals.

  4. Learning Objectives • Identify the various transmission media and topologies used in telecommunications networks. • Understand the fundamentals of wireless network technologies. • Explain the concepts behind TCP/IP. • Understand the seven layers of the OSI network model.

  5. Case 1: Best Buy, MedStar Health, and Unifi: The Challenges and Benefits of Wireless Mobile Applications • Geek Squad is a 24-hour response unit that offers computer and network support for home PC users or businesses without an onsite IT staff. • They use wireless Pocket PCs and other mobile devices to access company’s business applications. • The biggest challenge - typing on their small pocket PCs. • Many businesses that provide or manage employees’ mobile devices for accessing company information are developing their own software for mobile devices.

  6. Case Study Questions • What are the business advantages and limitations of the Best Buy Geek Squad’s use of their wireless Pocket PC mobile devices? How have they overcome the limitations of their mobile devices? • What are the software development challenges of wireless mobile devices? How are MedStar Health and Unifi meeting those challenges? • Why don’t the companies in this case use some of the thousands of software packages available for their wireless mobile devices? What are the advantages and limitations of this approach?

  7. Real World Internet Activity • Use the Internet to research wireless mobile devices like the Sprint PPC-6700. Do an analysis of the desirable features and limitations of the smart wireless mobile device you would most be willing to use in a work situation. Defend your choice.

  8. Real World Group Activity • While Best Buy has standardized on the Sprint PPC-6700 for its Geek Squad, MedStar Health lets their medical practitioners pick their own devices. Should companies mandate a standard wireless mobile device for their employees? • Discuss the pros and cons of this question; then formulate and defend a proposed solution.

  9. Network Concepts • Network • An interconnected chain, group or system • Number of possible connections on a network is N * (N-1) • Where N = number of nodes (points of connections on the network) • Example, if there are 10 computers on a network, there are 10 * 9 = 90 possible connections

  10. Metcalfe’s Law • The usefulness of a network equals the square of the number of users • On a small network, a change in technology affects technology only • On a large network like the Internet, a change in technology affects social, political and economic systems

  11. Telecommunications • Telecommunications • Exchange of information in any form (voice, data, text, images, audio, video) over networks

  12. Trends in Telecommunications

  13. Open Systems • Information systems that use common standards for hardware, software, applications and networks • Internet networking technologies are a common standard for open systems • Connectivity: • Ability of networked computers to easily access and communicate with each other and share information • Interoperability: • The ability of an open system to enable end user applications to be accomplished using different varieties of computer systems, software packages, and databases provided by a variety of interconnected networks

  14. Middleware • Any programming that serves to “glue together” two separate programs

  15. Digital Network Technologies • Rapid change from analog to digital network technologies • Analog: voice-oriented transmission, sound waves • Digital: discrete pulse transmission • Digital allows: • Higher transmission speed • Larger amounts of information • Greater economy • Lower error rates • Multiple forms of communications on same circuit

  16. Internet2 • Next generation of the Internet • High-performance network • In use at 200 universities, scientific institutions, communications corporations

  17. Business Value of Telecommunication Networks

  18. The Internet • Over 46 million servers (2004) • 710 – 945 million users (2004) • No central computer system • No governing body • No one owns it

  19. Internet Service Provider • ISP • A company that specializes in providing easy access to the Internet • For a monthly fee, you get software, user name, password and access • ISPs are connect to one another through network access points

  20. Popular uses of the Internet

  21. Using the Internet for business

  22. Business value of the Internet

  23. An Intranet • A network inside an organization • That uses Internet technologies (such as Web browsers and servers, TCP/IP protocols, HTML, etc.) • To provide an Internet-like environment within the organization • For information sharing, communications, collaboration and support of business processes • Protected by security measures • Can be accessed by authorized users through the Internet

  24. Enterprise Information Portal

  25. Extranet • Network links that use Internet technologies • To connect the Intranet of a business • With the Intranets of its customers, suppliers or other business partners

  26. Extranet Uses

  27. Case 2:Metric & MultistandardComponents Corporation • A secure network foundation can improve a small company’s operational efficiency, secure sensitive data, contain costs, and enhance employee connectivity and customer responsiveness. • It allows customers to securely track their orders in real time over the Web • It empowers customer-service agents with detailed account information to answer their customer’s enquiry • It can provide easy, inexpensive videoconferencing for remote workers, vendors, and customers.

  28. Case Study Questions • What were the most important factors contributing to MMCC’s success with its new, secure, self-managed network? Explain the reasons for your choices. • What are some of the business benefits and challenges of self-managed and externally managed networks? • Which type of network management would you advise small-to-medium business firms to use? Explain the reasons for your recommendation.

  29. Real World Internet Activity • Use the Internet to discover more about the telecommunications products and services and current business performance and prospects of Cisco Systems and Hi-Link and some of their many competitors in the telecom industry. • Which telecom hardware and software company and IT consulting firm would you recommend to a small-to-medium business with which you are familiar? Explain your reasons to the class.

  30. Real World Group Activity • In telecommunications network installation and management, as in many other business situations, the choice between “do it yourself” and “let the experts handle it” is a crucial business decision for many companies. • Debate this choice for small-to-medium businesses. See if you can agree on several key criteria that should be considered in making this decision, and report your conclusions to the class.

  31. Telecommunications network • Any arrangement where a sender transmits a message to a receiver over a channel consisting of some type of medium

  32. Telecommunications network components • Terminals: any input/output device that uses networks to transmit or receive data • Telecommunications Processors: devices that support data transmission and reception • Telecommunications Channels: media over which data are transmitted and received • Computers: all sizes and types • Telecommunications Control Software: programs that control telecommunications activities

  33. Telecommunications network model

  34. Wide Area Network (WAN) • Telecommunications network that covers a large geographic area Source: Courtesy of Cisco Systems Inc.

  35. Local Area Network (LAN) • Connect computers within a limited physical area such as an office, classroom, or building

  36. Virtual Private Networks (VPN) • A secure network that uses the Internet as its backbone but relies on firewalls, encryption and other security • A pipe traveling through the Internet

  37. VPN

  38. Client/Server networks • Clients: End user personal computers or networked computers • Interconnected by LANs • Servers: manage networks • Processing shared between clients and servers

  39. Client/Server Network

  40. Network Computing • Networks are the central computing resource of the organization • Thin clients: network computers and other clients provide a browser-based user interface

  41. Peer-to-peer networks • Networks that connect from one PC to another PC • Common use is the downloading and trading of files

  42. Peer-to-Peer Network

  43. Telecommunications Media • Twisted-pair wire: • Ordinary telephone wire • Copper wire twisted into pairs Source: Phil Degginger/Getty Images.

  44. Telecommunications Media • Coaxial cable: • Sturdy copper or aluminum wire wrapped with spacers to insulate and protect it Source: Ryan McVay/Getty Images.

  45. Telecommunications Media • Fiber-optic cable: • One or more hair-thin filaments of glass fiber wrapped in a protective jacket Source: CMCD/Getty Images.

  46. Problem of “The Last Mile” • Network providers use fiber optic to provide backbone • But houses are connected to the backbone via twisted-pair • Cannot get the benefit of the faster, better technology

  47. Wireless Technologies • Terrestrial microwave • Earthbound microwave systems that transmit high-speed radio signals in a line-of-sight path • Between relay systems spaced approximately 30-miles apart • Communications satellites • Satellite serves as relay stations for communications signals • Uses microwave radio signals

  48. Wireless Technologies • Cellular and PCS telephone and pager systems • Divide the geographic area into small areas or cells • Each cell has transmitter or radio relay antenna to send message from one cell to another • Wireless LANs • Radio signals within an office or building • Connect PCs to networks • Bluetooth • Short-range wireless technology • To connect PC to peripherals such as printer

  49. Wireless Web • Connect portable communications devices to the Internet

  50. Telecommunications Processors • Modems • Convert digital signals from a computer into • Analog frequencies that can be transmitted over ordinary telephone lines

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