信息与通信工程专业介绍英文版PPT课件.ppt

BriefIntroductiontoInformationandCommunicationEngineering 2011 5 30 1 BriefIntroductiontoInformationandCommunicationEngineering Amongalloftheessentialsforhumanexistence theneedtointeractwithothersranksjustbelowourneedtosustainlife Communicationisalmostasimportanttousasourrelianceonair water food andshelter Themethodsthatweusetoshareideasandinformationareconstantlychangingandevolving Whereasthehumannetworkwasoncelimitedtoface to faceconversations mediabreakthroughscontinuetoextendthereachofourcommunications Fromtheprintingpresstomobilephone eachnewdevelopmenthasimprovedandenhancedourcommunication 2 ThedevelopmentofCommunication 1 Inancienttimes informationcouldbetransferredthroughlightorsound 光通信 中国 烽火台 希腊 火炬的位置表示字母符号声通信 中国 击鼓鸣金 2 Beginningandturningpoint 1837 Morse telegram 1876 Bell telephone 1895 Marconi radio 3 ThedevelopmentofCommunication developmentoftransmissionchannelmulticorecable CoaxialCable opticalfiber多芯电缆 同轴电缆 光纤developmentofCommunicationcomponentsvacuumtube transistor integratecircuit largescaleintegratedcircuit真空管 晶体管 集成电路 大规模集成电路developmentoftransmissionmethodtelegram voice Muchcarriermodulation pulse codemodulation电报 声音 多载波调幅 pcmdevelopmentofrangeofmessagevoice text graph image声音 文字 图形 图像 4 ThedevelopmentofCommunication Aswitheveryadvanceincommunicationtechnology thecreationandinterconnectionofrobustdatanetworksishavingaprofoundeffect Earlydatanetworkswerelimitedtoexchangingcharacter basedinformationbetweenconnectedcomputersystems Currentnetworkshaveevolvedtocarryvoice videostreams text andgraphicsbetweenmanydifferenttypesofdevices Previouslyseparateanddistinctcommunicationformshaveconvergedontoacommonplatform Thisplatformprovidesaccesstoawiderangeofalternativeandnewcommunicationmethodsthatenablepeopletointeractdirectlywitheachotheralmostinstantaneously 5 ThefutureofCommunication 3 5w whateverwhereverwhoeverwhomeverwhenever任何人在任何时间 任何地点接收来自任何人的任何信息 6 ThefutureofCommunication 7 WhatisCommunication Asweallknow networkscansupportthewaywelearn thewayweworkandthewayweplay Livinginanetwork centricworld communicationisanessentialpartofourlives WhatisCommunication 8 WhatisCommunication Communicationinourdailylivestakesmanyformsandoccursinmanyenvironments Eachsituationhasitscorrespondingexpectedbehaviorsandstyles EstablishingtheRulesBeforebeginningtocommunicatewitheachother weestablishrulesoragreementstogoverntheconversation Theserules orprotocols mustbefollowedinorderforthemessagetobesuccessfullydeliveredandunderstood Amongtheprotocolsthatgovernsuccessfulhumancommunicationare AnidentifiedsenderandreceiverAgreeduponmethodofcommunicating face to face telephone letter photograph CommonlanguageandgrammarSpeedandtimingofdeliveryConfirmationoracknowledgementrequirements 9 EnsureQualityofCommunications Communicationbetweenindividualsisdeterminedtobesuccessfulwhenthemeaningofthemessageunderstoodbytherecipientmatchesthemeaningintendedbythesender Theexternalfactorsaffectingcommunicationarerelatedtothecomplexityofthenetworkandthenumberofdevicesamessagemustpassthroughonitsroutetoitsfinaldestination 10 EnsureQualityofCommunications Internalfactorsthatinterferewithnetworkcommunicationarerelatedtothenatureofthemessageitself Boththeinternalandexternalfactorsthataffectthereceiptofamessagemustbeanticipatedandcontrolledfornetworkcommunicationstobesuccessful Newinnovationsinnetworkhardwareandsoftwarearebeingimplementedtoensurethequalityandreliabilityofnetworkcommunications 11 CommunicationoverNetworks Beingabletoreliablycommunicatetoanyone anywhere isbecomingincreasinglyimportanttoourpersonalandbusinesslives Inordertosupporttheimmediatedeliveryofthemillionsofmessagesbeingexchangedbetweenpeopleallovertheworld werelyonawebofinterconnectednetworks Thesedataorinformationnetworksvaryinsizeandcapabilities butallnetworkshavefourbasicelementsincommon Rulesoragreementstogovernhowthemessagesaresent directed receivedandinterpretedThemessagesorunitsofinformationthattravelfromonedevicetoanotherAmeansofinterconnectingthesedevices amediumthatcantransportthemessagesfromonedevicetoanotherDevicesonthenetworkthatexchangemessageswitheachother 12 TheElementsofaNetwork Thediagramshowselementsofatypicalnetwork includingdevices media andservices tiedtogetherbyrules thatworktogethertosendmessages 13 TheElementsofaNetwork devices 14 TheElementsofaNetwork devices Switch themostcommondeviceforinterconnectinglocalareanetworksFirewall providessecuritytonetworksRouter helpsdirectmessagesastheytravelacrossanetworkWirelessRouter aspecifictypeofrouteroftenfoundinhomenetworks 15 TheElementsofaNetwork medium 16 TheElementsofaNetwork medium Foranetworktofunction thedevicesmustbeinterconnected Networkconnectionscanbewiredorwireless Inwiredconnections themediumiseithercopper whichcarrieselectricalsignals oropticalfiber whichcarrieslightsignals Inwirelessconnections themediumistheEarth satmosphere orspace andthesignalsaremicrowaves 17 TheElementsofaNetwork rules Humanbeingsoftenseektosendandreceiveavarietyofmessagesusingcomputerapplications theseapplicationsrequireservicestobeprovidedbythenetwork SomeoftheseservicesincludetheWorldWideWeb e mail instantmessaging andIPTelephony Devicesinterconnectedbymediumtoprovideservicesmustbegovernedbyrules orprotocols Inthechart somecommonservicesandaprotocolmostdirectlyassociatedwiththatservicearelisted 18 TheElementsofaNetwork rules 19 TheElementsofaNetwork messages Inthefirststepofitsjourneyfromthecomputertoitsdestination ourinstantmessagegetsconvertedintoaformatthatcanbetransmittedonthenetwork Alltypesofmessagesmustbeconvertedtobits binarycodeddigitalsignals beforebeingsenttotheirdestinations Thisistruenomatterwhattheoriginalmessageformatwas text video voice orcomputerdata Onceourinstantmessageisconvertedtobits itisreadytobesentontothenetworkfordelivery 20 TheElementsofaNetwork messages channel 21 Multipleservices multiplenetworks Traditionaltelephone radio television andcomputerdatanetworkseachhavetheirownindividualversionsofthefourbasicnetworkelements Inthepast everyoneoftheseservicesrequiredadifferenttechnologytocarryitsparticularcommunicationsignal Additionally eachservicehaditsownsetofrulesandstandardstoensuresuccessfulcommunicationofitssignalacrossaspecificmedium 22 Multipleservices multiplenetworks 23 ConvergedNetworks Technologyadvancesareenablingustoconsolidatethesedisparatenetworksontooneplatform aplatformdefinedasaconvergednetwork Theflowofvoice video anddatatravelingoverthesamenetworkeliminatestheneedtocreateandmaintainseparatenetworks Onaconvergednetworktherearestillmanypointsofcontactandmanyspecializeddevices forexample personalcomputers phones TVs butonlyonecommonnetworkinfrastructure 24 ConvergedNetworks 25 Whatisrequiredforus Convergednetworks whichcarryallcommunicationstypes data voice andvideo ononeinfrastructure provideanopportunitytoreducecostsandofferusersfeature richservicesandcontent However thedesignandmanagementofconvergednetworksrequiresextensivenetworkingknowledgeandskillsifallservicesaretobedeliveredasexpectedtousers Differenttypesofcommunicationsfl