Telecommunications, Networks, and Wireless Computing

1. Chapter 8 Telecommunications, Networks, and Wireless Computing

2. Objectives • What are the features of a contemporary corporate telecommunications system? On what major technology developments are they based? • What telecommunications transmission media should our organization use? • What kind of networks and network services are appropriate for our organization?

3. Objectives • What telecommunications applications can be used for electronic business and electronic commerce? • What issues should be addressed in telecommunications planning?

4. Management Challenges • Selecting appropriate technologies for enterprise networking • Managing bandwidth

5. The Corporate Telecommunications System Telecommunications System • Facilitation of electronic communication • Telephone systems • Broadcast and cable TV • Radio, satellite, and local area networks • Internet • Analog or digital

6. The Corporate Telecommunications System Features of Contemporary Telecommunications Systems Three Major Developments Shaping Contemporary Systems • Client/server computing • Packet switching • TCP/IP and other communications standards

7. The Corporate Telecommunications System A corporate telecommunications system Figure 8-1

8. The Corporate Telecommunications System Features of Contemporary Telecommunications Systems Client/Server Computing • Powerful personal computers connect to network with one or more server computers • Has extended networking to parts of business that could not be served by centralized architecture • Processing load balanced over many smaller machines

9. The Corporate Telecommunications System Features of Contemporary Telecommunications Systems Packet Switching • Messages broken into “packets” before transmission • Packets include destination and error-checking information • Packets travel independently using routers; reassembled into original message at destination

10. The Corporate Telecommunications System Packet-switched networks and packet communications Figure 8-2

11. The Corporate Telecommunications System Features of Contemporary Telecommunications Systems TCP/IP Transmission Control Protocol/Internet Protocol • Open suite of protocols for connectivity developed in 1970s • Provides standards for breaking messages into packets, routing them to destination addresses, and reassembling them at end • Allows for communication regardless of hardware/software

12. The Corporate Telecommunications System Features of Contemporary Telecommunications Systems TCP/IP: Four-Layer Reference Model • Application layer: Communication between applications and other layers • Transport layer: Acknowledging and sequencing packets to/from application • Internet layer: Addressing, routing, packaging data packets • Network interface layer: Placing packets on and receiving them from network medium

13. The Corporate Telecommunications System The Transmission Control Protocol/Internet Protocol (TCP/IP) reference model Figure 8-3

14. The Corporate Telecommunications System Transmission Media • Twisted wire • Copper wire twisted in pairs • Older analog transmission medium • Can be used for digital signals • Modems used for translating analog to digital • Coaxial cable: • Insulated copper wire • Faster, more interference-free than twisted pair • Difficult to install; doesn’t support analog signals

15. The Corporate Telecommunications System Functions of the modem Figure 8-4

16. The Corporate Telecommunications System Transmission Media • Fiber optics • Strands of clear glass fiber bound into cables • Data sent as pulses of light • Faster, lighter, more durable • Difficult to install; more expensive • Used in high-capacity optical networks • Currently slowed by need to convert back and forth to electrical data • Can use multiplexing; allows one channel to carry several transmissions

17. The Corporate Telecommunications System Transmission Media • Wireless Transmission • Use electromagnetic spectrum • Microwave and infrared use high-frequency radio signals • Paging systems, cellular telephones, PDAs, mobile data networks • Wireless communication requires compatible standards • Security/privacy issues

18. The Corporate Telecommunications System Frequency ranges for communication media and devices Figure 8-5

19. The Corporate Telecommunications System Amoco’s satellite transmission system Figure 8-6

20. The Corporate Telecommunications System Transmission Media Transmission Speed • Bps: Bits per second • Baud rate: Rate of signal changes • One signal change = cycle • Transmission capacity is function of frequency • Bandwidth: Range of frequencies accommodated on a particular channel

21. The Corporate Telecommunications System Transmission Media Transmission Speed

22. Communications Networks Local Area Networks • Connects computers and other digital devices within 2000 ft radius • Cabling or wireless technology links computers, network interface cards, and software • Ethernet • Network Operating System (NOS) • Client/server or peer-to-peer architecture • Star, bus, and ring topologies

23. Communications Networks A local area network (LAN) Figure 8-7

24. Communications Networks Network topologies Figure 8-8

25. Communications Networks Wireless Networks: Wi-Fi and Bluetooth • Use radio waves to connect stations • 802.11b: Current standard; 54 Mbps in 2.4 GHz range • Infrastructure mode: Wireless devices communicate with wired LAN via access points • Ad-hoc mode: Peer-to-peer mode; wireless devices communicate with each other directly

26. Communications Networks An 802.11 wireless LAN Figure 8-9

27. Communications Networks Wireless Networks: Wi-Fi and Bluetooth • Hot spot: Geographic location in which an access point provides public Wi-Fi network service • Bluetooth: Standard for wireless personal area networks that can transmit up to 722 Kbps within 10-meter area

28. Communications Networks Wide Area Networks • Span broad geographic distances • Can consist of combination of: • Switched lines • Dedicated lines • Microwave • Satellite communications • Private WANs expensive to support

29. Communications Networks Wide Area Networks • Metropolitan Area Network (MAN) • Scope between LAN and WAN • Limited distance; faster and less expensive than WAN • Value-Added Networks • Private, third-party managed, data only networks • Subscription basis

30. Communications Networks Window on Organizations Is the World Falling for Wi-Fi? • What management, organization, and technology factors account for different patterns of Wi-Fi adoption in various countries? • What value can Wi-Fi service provide to businesses?

31. Communications Networks Broadband Network Services and Technologies • Frame relay • Asynchronous transfer mode (ATM) • Integrated Services Digital Network (ISDN) • Digital subscriber line (DSL) • T1 line • Network convergence

32. Electronic Business and Electronic Commerce Technologies Electronic Mail and Groupware • E-mail • Eliminates telephone tag and costly long-distance telephone charges • Groupware • Enables work groups at different locations to participate in discussion forums and work on shared documents and projects

33. Electronic Business and Electronic Commerce Technologies Window on Management Monitoring Employees on Networks: Unethical or Good Business? • Should managers monitor employee e-mail and Internet usage? Why or why not? • Describe an effective e-mail and Web use policy for a company.

34. Electronic Business and Electronic Commerce Technologies Voice Mail and Fax • Voice mail • Digitizes spoken message and transmits it over a network • Fax • Digitizes and transmits documents over telephone lines

35. Electronic Business and Electronic Commerce Technologies Teleconferencing, Dataconferencing, and Videoconferencing • Teleconferencing • Ability to confer with a group of people simultaneously • Data conferencing • Two or more users can edit and modify data files simultaneously • Videoconferencing • Participants are able to see each other over video screens

36. Electronic Business and Electronic Commerce Technologies Digital Information Services, Distance Learning, and E-Learning • Digital Information Services: • Online services providing general and business information, such as LexisNexis, AOL, Dow Jones News • Distance learning • Education or training delivered over a distance to individuals in one or more locations • E-learning • Instruction delivered online using the Internet or private networks

37. Electronic Business and Electronic Commerce Technologies Electronic Data Interchange • Computer-to-computer exchange between two organizations of standard transaction documents, such as invoices, purchase orders • Minimizes paper-handling and data input; lowers transaction costs • Transmits structured data with fields, unlike e-mail

38. Electronic Business and Electronic Commerce Technologies Electronic data interchange (EDI) Figure 8-10

39. Developing a Business-Driven Telecommunications Plan Implementation Issues: Seven Factors • Distance • Services • Points of access • Utilization • Cost • Security • Connectivity

40. Chapter 8 Case Study Will New Systems Keep Delta Flying? • Analyze Delta using the competitive forces and value chain models. • What is Delta’s business strategy? What is the role of information systems and telecommunications technology in this strategy?

41. Chapter 8 Case Study Will New Systems Keep Delta Flying? • Assess Delta’s Digital Nervous System (DNS) effort. What value does it provide the company? How does it support Delta’s business strategy? • What problems at Delta can be solved with information systems? What problems cannot be solved with systems?