IS312 Information Systems for Business

1. IS312 Information Systems for Business Lecture 5 Telecommunication & Network Applications [ Ch. 7 & Appendix B ]

2. LEARNING OBJECTIVES Benefits of telecommunication networks in business Networking basics: Architecture, Topology, Protocols, Media Network applications

3. Computer Networks Connected computers: Work together Are interdependent Exchange data with each other

4. Size of Computer Networks Home computer network National computer network Global computer network

5. Mobile Computing The characteristics, mobility and broad reach, create five value-added attributes that break the barriers of geography and time: Ubiquity : regardless of user’s location Convenience Instant connectivity Personalization Localization of products and services

6. Benefits of A Connected World • Networks offer many advantages for a business including • Sharing resources • Providing opportunities • Reducing travel

7. Challenges of A Connected World • Networks have created a diverse, yet globally connected world by eliminating time and distance, networks make it possible to communicate in ways not previously imaginable • Even though networks provide many business advantages, they also create increased challenges in • Security • Social, ethical, and political issues

8. Benefits of Business Mobility • Enhance mobility • Provides immediate data access • Increases location and monitoring capability • Improves work flow • Provides mobile business opportunities • Provides alternative to wiring

9. Challenges of Business Mobility • Protecting against theft • Protecting wireless connections • Preventing viruses on a mobile device • Addressing privacy concerns with RFID (Radio Frequency Identification) and LBS (Local Base Service)

10. Types of Networks A computer network is a system that connects computers via communications media so that data can be transmitted among them. Local area networks Wide are network Value-added network Enterprise network

11. Local Area Network

12. Wide Area Network

13. Enterprise Network

14. Human Communication

15. Computer Communication Senders and Receivers There must a be a sender and a receiver with something to share via a messageto facilitate communication Communication Medium(Channel) A medium must exist between the sender and receiver over which the message travels (e.g., a cable) Protocols Procedures, rules, or standards must be followed by computers when sending or receiving data

16. Coding, Sending, Decoding

18. The Telecommunications System A telecommunications system consists of hardware and software that transmit information from one location to another.

19. Typical Telecommunications System

20. Analog and Digital Signals

21. Communications Processors Modem – Modulation/Demodulaion: covert analog signals to digital signals and vice versa Multiplexer – a single channel can carry data simultaneously from many sources Front-End Processor – mainframe communicates with many computers

22. Modems • Digitizing (change info to bits 0-1) • Modem Modulator/Demodulator -(code/decode digital/analog)

23. Basic Networks

24. Personal Area Network • Personal area networks (PAN) - Provide communication over a short distance that is intended for use with devices that are owned and operated by a single user • Bluetooth - Wireless PAN technology that transmits signals over short distances between cell phones, computers, and other devices

25. Wireless LAN • Wireless LAN (WLAN) - A local area network that uses radio signals to transmit and receive data over distances of a few hundred feet • Wireless fidelity (Wi-Fi) - A means by which portable devices can connect wirelessly to a local area network, using access points that send and receive data via radio waves

26. Wireless MAN • Wireless MAN (WMAN) - A metropolitan area network that uses radio signals to transmit and receive data

27. Wireless MAN • Worldwide Interoperability for Microwave Access (WiMAX) - A communications technology aimed at providing high-speed wireless data over metropolitan area networks

28. Wireless WAN - Cellular • Wireless WAN (WWAN) - A wide area network that uses radio signals to transmit and receive data

29. Wireless WAN - Cellular • Smart phone - Offer more advanced computing ability and connectivity than basic cell phones • 3G - A service that brings wireless broadband to mobile phones • Streaming – A method of sending audio and video files over the Internet

30. Wireless WAN - Satellite • Satellite - A space station that orbits the Earth receiving and transmitting signals from Earth-based stations over a wide area

31. Network Basics • Networks are differentiated by the following: • Architecture - peer-to-peer, client/server • Topology - bus, star, ring, hybrid, wireless • Protocols - Ethernet, Transmission Control Protocol/Internet Protocol (TCP/IP) • Media - coaxial, twisted-pair, fiber-optic

32. Protocols • Protocol - A standard that specifies the format of data as well as the rules to be followed during transmission • Interoperability - The capability of two or more computer systems to share data and resources, even though they are made by different manufacturers

33. Ethernet • Ethernet- A physical and data layer technology for LAN networking

34. Transmission Control Protocol/ Internet Protocol • TCP/IP applications • File transfer protocol (FTP) • Simple mail transfer protocol (SMTP) • Hypertext transfer protocol (HTTP) • Simple network management Protocol (SNMP)

35. Network Protocols Rules or procedures used to transmit and receive data Specify: Connection of computers to the network Error checking Data compression Signal of finished transmission Signal of received message Examples of protocols: OSI, TCP, IP, UDP, IPX, SPX, etc.

36. The Four Layers of the TCP/IP Protocol

37. Architecture • There are two primary types of architectures • Peer-to-peer (P2P) network • Client/server network

38. Peer-to-peer Networks • Peer-to-peer (P2P) network - Any network without a central file server and in which all computers in the network have access to the public files located on all other workstations

39. Client/Server Networks • Client - A computer that is designed to request information from a server • Server - A computer that is dedicated to providing information in response to external requests • Client/server network - Model for applications in which the bulk of the back-end processing takes place on a server, while the front-end processing is handled by the clients

40. Client/Server Networks • Network operating system (NOS) - The operating system that runs a network, steering information between computers and managing security and users • Packet-switching -Occurs when the sending computer divides a message into a number of efficiently sized units called packets, each of which contains the address of the destination computer • Router - An intelligent connecting device that examines each packet of data it receives and then decides which way to send it onward toward its destination

41. Client/Server Networks

42. Packet Switching

43. Packet Switching

44. Router

45. Router

46. Topology

47. Ring Network

48. Star Network

49. Bus Network

50. Hybrid Network