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1、1Telecom.pptBasic TelecommunicationsVocabulary, concepts, more “bullet proofing”Touch on just a few basic pointsessentials of technology and where its goingessentials of regulation and where its goingRaise for discussion certain management issues12Telecom.pptBasic Telecom Terms and Concepts, 1Transm
2、ission facilitiesTwisted pairCoaxial cableMicrowaveSatelliteFiber opticsWirelessSignalingAnalog-continuousDigital-discrete23Telecom.pptBasic Telecom Terms and Concepts, 2Analog signalingAM, FM, etc.LimitationsError correctionEncryptionDigital signalingComputer friendlyFacilitatesError correctionEncr
3、yptionFits with fiber optic transmission facilities“The way the world is going”Modems“Modulator-demodulator”A to D and D to ABecause the voice network is analogAt the handset34Telecom.pptBasic Telecom Terms and Concepts, 3SwitchingThe cloudThe cloud is expensiveSwitching makes better use of the clou
4、dKinds of switchingCircuit switchingMessage switchingPacket switchingAnd the InternetAnd ATMBroadcastingCellular45Telecom.pptBasic Telecom Terms and Concepts, 4Voice networksRBOCsOther local telcosLong distance carriersCable companies?Data networksLANWANetc.Often (usually) use voice network transmis
5、sion facilitiesCable TV networksMicrosoft and $1 billion/yr R&D on the set top box56Telecom.pptWhere Do Networks Come From?Long distance carriersAT&T, MCI, Sprint, etc.“Common carriers”VANsAnd the InternetThe Internet and ISPsPrivate networks67Telecom.pptTelecom Standards and RegulationVoice network
6、 regulation (U.S.A.)1934-19811982-presentRBOCs etc.-local loop provider regulated, but less so under the Telcom Act of 1996Long distance: largely unregulatedData communications?Basically, anything goesBut whose transmission facilities are used?Largely: from the voice networksVoice networksInterconne
7、cted world-wideStandardsLegal requirementsData networks? Cable?Recent (de)regulatory actions78Telecom.pptThe InternetThe worlds first network for making data callsNB telexHistory and cultureARPA net, nuclear attackNSF net and the open communityGovernanceDesign policiesSimple protocols (e.g., TCP/IP)
8、Public and openContinuing rapid growthElectronic commerceConsumer-orientedBusiness-to-businessUser base growing beyond “young male nerds”Cost of use?89Telecom.pptThe Last Mile ProblemWhat it isPossible solutionsUpgrades of existing plantCableFiber opticsWirelessThe competitive scene TODAYCable compa
9、nies (and Microsoft)DSL and the telcos (and Microsoft)Other telcosWhy is the computer industry mucking in the last mile problem?Prognostications?910Telecom.pptThe Protocols Problem(s)Important concept: layered architectures for telecommunications OSI reference model, 7 layersAlso important for softw
10、are in generalAbstraction as a way of handling complexityImportance of standardizationde jurede factoInternet?Development of standards to dateTelephonyData communicationsAnd the InternetFor electronic commerce? IncompleteManagerial/decision issues?1011Telecom.pptFurther Issues for DiscussionOutsourc
11、ing of network provision and managementOptionsManagement issuesImagine you are about to receive a sales callCommitment to standardsWhich ones?Who to believe, trust, or bet on?Assuming AAA networks (the Internet on steroids),Productivity opportunities? (and what will it take to realize them)Industria
12、l-organizational consequences?1112Telecom.pptThis slide unintentionallyleft blank1213Telecom.pptComputer Mediated Communication (CMC): 1TelexA world-wide telecommunications systemUp and running for 100 yearsDigital signalingTelephoneA world-wide telecommunications systemUp and running for 50 yearsIs
13、nt this enough?Whats missing?1314Telecom.pptCMC: 2Telephones are everywhere. From an arbitrary telephone you can call nearly any other telephone.Computers are . all over.From an arbitrary computer, why cant you make a data call to nearly any other computer?Data communications is inherently easier (i
14、n many ways) than voice communication.So why cant you make those data calls?1415Telecom.pptCMC: 3Increasingly, you can make those data callsAnd theres a lot of great stuff out there nowCall on special networksNSF NetCompuserveProdigyetc.And THE INTERNET.An internet: a network of networksThe Internet: The Mother of All InternetsThe world we are coming to“Anything, anytime, anywhere.”15
