Bài giảng Information Systems in Business - Chapter 6 Telecommunications and Networks

Telecommunicationsand NetworksChapter6McGraw-Hill/IrwinCopyright © 2011 by The McGraw-Hill Companies, Inc. All rights reserved.Understand the concept of a networkApply Metcalfe’s law in understanding the value of a networkIdentify major developments and trends in the industries, technologies, and business applications of telecommunications and Internet technologiesLearning ObjectivesProvide examples of the business value of Internet, intranet, and extranet applicationsIdentify the basic components, functions, and types of telecommunications networks used in businessExplain the functions of major components of telecommunications network hardware, software, media, and servicesLearning ObjectivesExplain the concept of client/server networkingUnderstand the two forms of peer-to-peer networkingExplain the difference between digital and analog signalsLearning ObjectivesNetwork ConceptsInterconnected chain, group, or systemConnections created by nodes Exponential growthMetcalf’s LawUsefulness, or utility, of a network Equals the square of the number of usersMore users = more useful Network Component AlternativesTelecommunications MediaTwisted-Pair WireSimilar to telephone wireCoaxial CableWire wrapped with insulationFiber-Optic CableOne or more hair-thin filaments of glass Communications SatellitesGeosynchronous orbit Serve as relay stationsWireless LANSWireless radio-wave technology BluetoothShort-range wireless technologyOther Wireless SystemsCellular phones, Mobile radio, PDAsTelecommunications vital and pervasiveWeb-enabled e-business processesWireless TechnologiesOther Wireless SystemsCellular phonesMobile radioPDAsTelecommunications pervasive roleWeb-enabled e-business processesElectronic commerceEnterprise collaborationOther applications Business operations, management, strategic objectivesWireless TechnologiesThe Wireless WebWeb-enabled appliances proliferateSmart telephones, pagers, PDAsAll are very thin clients in wireless networksTelecommunications ProcessorsModemsMost common type Modulation and demodulationConverts for transmission over telephone linesDigital signal to analogAnalog to digitalTelecommunications SoftwareMay reside in PCs, servers, mainframes, and communications processorsVital part of all telecommunications networksUsed to manage network performanceWANs often use telecommunications monitors or teleprocessing monitorsOther networks use operating system softwareMiddleware helps diverse networks communicate with each otherNetwork Management FunctionsTraffic ManagementSecurityNetwork MonitoringCapacity PlanningNetwork Architectures and ProtocolsProtocolRules and proceduresHandshakingExchanging predetermined to agree on a protocolNetwork ArchitectureMaster plan of standardsGoal is to promote an open, simple, flexible, and efficient telecommunications environmentOSI ModelOpen Systems Interconnection ModelSeven-layer standard for network architecturesControls how messages should be transmittedEnsures consistency among products