1. Management Information Systems, 4 th Edition 1 Chapter 6 Information Technology in Business: Telecommunications and Networks

2. Management Information Systems, 4 th Edition 2 Learning Objectives Explain why successful managers must be familiar with telecommunications concepts and terminology Describe the principles of communication within a computer system and among computers Identify the major media and devices used in telecommunications

3. Management Information Systems, 4 th Edition 3 Learning Objectives (Cont.) List and explain the functions of different network layouts and the concept of protocols Explain how telecommunications can improve operations in organizations Cite the latest developments in telecommunications media and transmission speed

4. Management Information Systems, 4 th Edition 4 Telecommunications in Business Transmittal of data from one computer to another over a distance Telecommunications has improved business in three main ways: –Better communication –Higher efficiency –Better distribution of data

5. Management Information Systems, 4 th Edition 5 Telecommunications in Daily Use Cellular Phones Videoconferences Voice Mail Facsimile Information Kiosks Pay at the Pump

6. Management Information Systems, 4 th Edition 6 Easy Passing Web-Based Electronic Commerce Worldwide Peer-to-Peer File Sharing –Napster, Gnutella, BearShare, Morpheus –With directory –Without directory Telecommunications in Daily Use (Cont.)

7. Management Information Systems, 4 th Edition 7 Telecommunications in Daily Use (Cont.)

8. Management Information Systems, 4 th Edition 8 Data Communications Any transfer of data within a computer, between a computer and another device, or between two computers Parallel and Serial Data Communications

9. Management Information Systems, 4 th Edition 9 Data Communications (Cont.)

10. Management Information Systems, 4 th Edition 10 Simplex –One-way in one direction Half-Duplex –One-way in two directions Full-Duplex –Two-way in two directions Communication Direction

11. Management Information Systems, 4 th Edition 11 Communication Direction (Cont.)

12. Management Information Systems, 4 th Edition 12 Parity Check –Error detection method –Checks that no bits are added or deleted during transmission –Odd Parity Check looks for an odd number of ones –Even Parity Check looks for even number of ones Error Detection

13. Management Information Systems, 4 th Edition 13 Communications medium –Physical medium through which data can be communicated –Telephone lines, television cables Capacity –Speed at which data are communicated –Also called the transmission rate –It is often called “bandwidth” Bandwidth is measured in bits per second (bps) –The greater the capacity, the faster the transmission Bandwidth and Media

14. Management Information Systems, 4 th Edition 14 Bandwidth and Media (Cont.)

15. Management Information Systems, 4 th Edition 15 Bandwidth –Narrowband is low speed –Broadband has greater capacity Media –A medium is any means by which data can be transmitted Bandwidth and Media (Cont.)

16. Management Information Systems, 4 th Edition 16 A medium’s capacity is determined by the range of bits per second at which it can operate Baud is the number of signals per minute Repeater receives and strengthens signals before sending them on Transmission speed

17. Management Information Systems, 4 th Edition 17 Transmission Speed (Cont.)

18. Management Information Systems, 4 th Edition 18 Telephone line made of a pair of copper wires twisted to reduce electromagnetic interference (EMI) Twisted Pair

19. Management Information Systems, 4 th Edition 19 Coaxial Cable Commonly used for cable television transmission –More expensive than twisted pair –Greater transmission rate than twisted pair –Much less susceptible to EMI

20. Management Information Systems, 4 th Edition 20 High-frequency, short radio-frequency (RF) waves –Terrestrial microwave –Satellite microwave Microwaves

21. Management Information Systems, 4 th Edition 21 Optical Fiber Fiber-optic technology uses light instead of electricity to transmit data

22. Management Information Systems, 4 th Edition 22 Characteristics of Media

23. Management Information Systems, 4 th Edition 23 Modulation Modification of a digital signal into an analog signal Demodulation –Modification of an analog signal into a digital signal

24. Management Information Systems, 4 th Edition 24 Analog vs. Digital –Analog: A continuous series of waves –Digital: A series of discrete bits Modulation (Cont.)

25. Management Information Systems, 4 th Edition 25 Modulation (Cont.)

26. Management Information Systems, 4 th Edition 26 Modulation (Cont.) Amplitude Modulation (AM) Frequency Modulation (FM) Phase Modulation Modems –Devices that modulate and demodulate signals

27. Management Information Systems, 4 th Edition 27 Modulation (Cont.) Figure 6.9 Multiplexing

28. Management Information Systems, 4 th Edition 28 Networks LANs (Local Area Networks) –Networks within a building, or within a group of adjacent buildings WANs (Wide Area Networks) –Networks that cross organizational boundaries or reach outside the company Value-added networks (VANs) Wireless communication

29. Management Information Systems, 4 th Edition 29 Network Topology Physical layout of the nodes in a network –Star –Ring –Bus –Tree

30. Management Information Systems, 4 th Edition 30 Network Topology

31. Management Information Systems, 4 th Edition 31 Networking Hardware Network Interface Card Hub Switch Bridge Router

32. Management Information Systems, 4 th Edition 32 Virtual Private Network A combination of private and public lines A link between a private network and the Internet “Virtual” refers to the illusion that the use is accessing a private network directly

33. Management Information Systems, 4 th Edition 33 Protocols Communication protocols –Rules governing the communication between computers or between computers and other computer-related devices Network protocols –Rules governing a network of devices

34. Management Information Systems, 4 th Edition 34 Protocols (Cont.) LAN Protocols –Polling –Contention –Token passing WAN Protocols –OSI (Open Systems Interconnection) Standard protocol model Seven layers

35. Management Information Systems, 4 th Edition 35 Protocols (Cont.)

36. Management Information Systems, 4 th Edition 36 Switching Techniques Circuit Switching –Message is communicated in its entirety from the transmitting computer to the receiving computer Packet Switching –Message is divided into packets of bytes and transmitted via several nodes –TCP/IP

37. Management Information Systems, 4 th Edition 37 Switching Techniques (Cont.)

38. Management Information Systems, 4 th Edition 38 The Changing Business Environment Cellular Phones Teleconferencing Voice Mail Facsimile

39. Management Information Systems, 4 th Edition 39 A Variety of Services Cable Digital Subscriber Line (DSL) T1 and T3 Lines Satellite Fixed Wireless Gigabit Ethernet Optical Carrier

40. Management Information Systems, 4 th Edition 40 A Variety of Services (Cont.)

41. Management Information Systems, 4 th Edition 41 A Wireless Revolution Popular Wireless Technologies Would You Like Wi-Fi With That? Combining Technologies

42. Management Information Systems, 4 th Edition 42 Wireless Technologies (Cont.)

43. Management Information Systems, 4 th Edition 43 Wireless Technologies (Cont.)

44. Management Information Systems, 4 th Edition 44 Ethical and Societal Issues Telecommuting: Pros and Cons Pros –Saves travel cost and time –Decreases pollution –May reduce unemployment. –Productivity higher among telecommuters

45. Management Information Systems, 4 th Edition 45 Ethical and Societal Issues Telecommuting: Pros and Cons Cons –Employers tend to pressure telecommuters to work harder than workers in the office. –No office to foster new social ties and camaraderie. –May negatively impact some segments of the economy Restaurants Downtown business and industries

46. Management Information Systems, 4 th Edition 46 Summary Telecommunications concepts and terminology Communication within a computer system and among computers Telecommunications media and devices Network layouts and protocols Telecommunications impact on operations Telecommunications developments and speed