Management Information Systems By Effy Oz & Andy Jones Chapter 5: Business Networks and Telecommunications www.cengage.co.uk/oz

Objectives Describe business and home applications of digital telecommunications Identify the major media and devices used in telecommunications Explain the concept of protocols

Objectives (continued) Compare and contrast various networking and Internet services List networking technologies and trends that are likely to have an impact on businesses and information management in the near future Discuss the pros and cons of telecommuting

Telecommunications in Business Telecommunications: transmittal of data and information Allows communications over large distances Network technologies bring about several improvements to business process

Telecommunications in Business (continued) Advantages of telecommunications Better business communication Geographical distance irrelevant Greater efficiency Information becomes immediately available Better distribution of data

Telecommunications in Business (continued) Advantages of telecommunications Instant transactions Flexible and mobile workforce Alternative channels However network security is risk

Telecommunications in Daily Use: Mobile Phones American term of “cellular phone” is derived from areas of service called cells Use computerized transceiver Transmits and receives signals Transmit and receive calls almost anywhere Other uses E-mail and faxing GPS Digital cameras Major advantage is mobility

Videoconferencing Videoconferencing: transmitted images and speech Brings conference rooms thousands of miles apart together Save on multiple costs Travel Lodging Time

Fax Fax: Transmission and reception of images over telephone line Fax machine digitizes image and transmits representative bits to other fax machine Can be sent through Internet Uses special software

Wireless Payments and Warehousing Radio frequency identification (RFID) technology enables quick transactions and payments Used in gas stations and wireless toll plazas Facilitates payments Used in warehouses Check availability Locate items to be picked up and stored

Peer-to-Peer File Sharing Peer-to-Peer file sharing: locate and download files from online computer through Internet LimeWire KaZaa Morpheus Exchange music and video files Raises many issues with copyright violation BitTorrent: Download segments of files from multiple sources

Web-Empowered Commerce Increasingly fast communication allows businesses options Research Market Educate Train Shop Entire industries created by Web Online exchanges and auctions

Bandwidth and Media Bandwidth: speed at which data are communicated Bits per second: unit of measure for bandwidth Baseband: carry only one transmission at a time Broadband: carry multiple transmissions simultaneously

Bandwidth (continued)

Media Several types of communications media Tangible or intangible Twisted pair cable Coaxial cable Optical fibre Intangible media Microwave radio technologies

Media (continued) Twisted pair cable: pairs of insulated copper wires twisted together Twisting reduces electromagnetic interference Low cost Used in networking devices Coaxial cable: for cable television transmission Used for Internet Optical fibre: uses light to represent bits Not susceptible to interference

Media (continued) Microwaves: high-frequency radio waves that can carry signals over long distances Used in radio-frequency technologies Signals transmitted by satellite links Geostationary satellites are farther away from the Earth Electrical power lines: electrical power grid used for telecommunication

Media (continued)

Networks Network: combination of devices (nodes) connected through communication channels Any compatible device can transmit and receive on a network

Types of Networks Three basic types of networks Local area network (LAN): established by single organisation and shared among employees Server: single computer often used as central repository of programs and files for all computers Peer-to-peer LAN: no central device controls communications

Types of Networks (continued) Wireless LANs (WLANs): easier installation and more scalable Scalability: ease of expanding system Wireless networks less secure Metropolitan area network (MAN): links multiple LANs within large city Wide area network (WAN): far-reaching system of networks composed of LANs or MANs

Types of Networks (continued) Value-added networks (VANs): networks with enhanced services Reliability Management Maintenance Internet service providers (ISPs): preferred method of conducting commerce

PANs Personal area network (PAN): wireless network designed for handheld and portable devices Used by one or two people Transmission speed slower Maximum distance 10 metres

Networking Hardware Networks use variety of devices to connect computers and peripheral devices Network interface card: connects through cable or wireless antenna to middle device Middle device connects to LAN or WAN Hub: central location to connect computers Switch: controls direction of communications

Networking Hardware (continued) Bridge: connects two networks Router: routes data packets to next node Repeater: amplifies or regenerates signals Modem: translates communication signals form analog to digital and vice versa Dial-up connection: slower type of connection through modem

Virtual Private Networks Virtual private network (VPN): alternative to creating LAN Does not require leasing of lines Utilizes Internet, a public network to simulate a private network Enables intranets and extranets

Switching Techniques Circuit switching: dedicated channel established for duration of transmission Packet switching: message broken into packets Packet: group of bits transmitted together Frame relay: high-speed packet-switching protocol used in WANs Variable-sized packets routed quickly

Switching Techniques (continued)

Protocols Protocol: set of rules governing communication between computers Protocol is like human language and basic understanding Some protocols designed for WANs, LANs, and wireless communications Most important set of protocols called TCP/IP

TCP/IP TCP/IP: Transmission Control Protocol/Internet Protocol Ensures packets arrive accurately Ensures delivery of packets from node to node, respectively Internet backbone: highest speed channels Host: computer connect directly to backbone IP number: unique identification for device DNS: Domain Name Service maintains character-based names of IP numbers

TCP/IP (continued) Static IP number: permanent number assigned to device Dynamic IP number: temporary IP number assigned for duration of connection

Ethernet Ethernet: LAN protocol using coaxial cable Gigabit Ethernet: faster Ethernet connections Devices on network contend with other devices for transmission time CSMA/CD protocol ensures no collisions in transmission

Wireless Protocols IEEE 802.11: known as Wi-Fi Supports wireless communication within 100 metres of router Max speed 11 Mbps Access point (hotspot): allows Internet access within range of equipment Encryption: ability to scramble and code messages Use keys shared between sender and receiver Bluetooth: allows devices to communicate within 10 metres

Wireless Protocols (continued) Worldwide Interoperability for Microwave Access (WIMAX): increases range and speed of wireless communication Works with metropolitan area networks Mobile Broadband Wireless Access (MBWA): similar to cell phone communications Compatible with IP services Compatible with Wi-Fi and Bluetooth

Wireless Protocols (continued)

Generations in Mobile Communications Networking professionals refer to generations of mobile communication technologies First generation analog Second generation used digital voice encoding Third generation stepped up speeds Fourth Generation digital Packet switching Higher security

Internet Networking Services Variety of options to choose from when subscribing to network services Downstream: speed of receiving from network Upstream: speed of transmitting to network

Cable Internet links provided by television cable firms Cable connected to Internet server At residence, cable split into TV set and computer Cable shared by all subscribers

Digital Subscriber Line (DSL) Digital subscriber line (DSL): data remains digital through entire transmission Uses telephone lines connected to DSL bridge Several types of DSL Asymmetric allows different upstream and downstream rates Transmission rates closely related to distance from telephone company

Satellite Satellite services use microwaves Service provider installs dish antenna, used as communications satellite Speeds up to 45 Mbps GPS free satellite service

Fixed Wireless Fixed wireless: point-to-point transmission between two stationary devices Wireless Internet service provider (WISP) Provides fixed wireless service Highly modular and scalable

Optical Carrier Optical carrier Uses basic unit of 51.84 Mbps Used by Expensive High connection speeds Uses basic unit of 51.84 Mbps Used by ISPs Search engines Content-rich Web sites

Broadband over Power Lines (BPL) Broadband over Power Lines (BPL): uses electric power lines to carry digital signals Used by utility companies Monitor power consumption Detect power failure Track power outages

The Future of Networking Technologies: Broadband Telephoning Voice over Internet Protocol: uses Internet connection to conduct telephone conversations Free of charge Different quality of sound from traditional telephone services Does not allow calls to emergency numbers such as 999

Radio Frequency Identification RFID tags tiny and need little power Objects are embedded with tags that contain radio transceiver Tags encoded with electronic product code Readers decode data stored in tag’s memory and data passed to host computer

Future Uses of RFID

Converging Technologies Convergence occurs in networking technology Cell phones can act as Web phones Television sets connect to Internet Wireless technologies combined in same device enhance functionality

Summary Telecommunications is communication over distance Telecommunications technology has changed the business environment Different media have different bandwidths Networks are classified according to reach and complexity Network can be turned into a virtual private network (VPN)

Summary (continued) Two ways to switch a communication line: packet switching and circuit switching Network protocols are sets of rules to which all devices on network must adhere The Internet adheres to the TCP/IP protocol Wireless technologies make it easy and affordable to create wireless LANs organisations and individuals have variety of choices when subscribing to networking services

Summary (continued) As Internet links become faster, Internet telephoning is gaining in popularity Wireless technologies support the increasingly popular RFID technologies Much like hardware, telecommunications technologies are merging Increasing numbers of employees now telecommute