40-Ethernet - distributed packet switching for local computer networks.pdf40-Ethernet - distributed packet switching for local computer networks.pdf

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COMPUTERSYSTEMSGBELL,SFULLERANDDSIEWIOREK,EDITORSETHERNETDISTRIBUTEDPACKETSWITCHINGFORLOCALCOMPUTERNETWORKSROBERTMMETCALFEANDDAVIDRBOGGSXEROXPALOALTORESEARCHCENTERETHERNETISABRANCHINGBROADCASTCOMMUNICATIONSYSTEMFORCARRYINGDIGITALDATAPACKETSAMONGLOCALLYDISTRIBUTEDCOMPUTINGSTATIONSTHEPACKETTRANSPORTMECHANISMPROVIDEDBYETHERNETHASBEENUSEDTOBUILDSYSTEMSWHICHCANBEVIEWEDASEITHERLOCALCOMPUTERNETWORKSORLOOSELYCOUPLEDMULTIPROCESSORSANETHERNETSSHAREDCOMMUNICATIONFACILITY,ITSETHER,ISAPASSIVEBROADCASTMEDIUMWITHNOCENTRALCONTROLCOORDINATIONOFACCESSTOTHEETHERFORPACKETBROADCASTSISDISTRIBUTEDAMONGTHECONTENDINGTRANSMITTINGSTATIONSUSINGCONTROLLEDSTATISTICALARBITRATIONSWITCHINGOFPACKETSTOTHEIRDESTINATIONSONTHEETHERISDISTRIBUTEDAMONGTHERECEIVINGSTATIONSUSINGPACKETADDRESSRECOGNITIONDESIGNPRINCIPLESANDIMPLEMENTATIONAREDESCRIBED,BASEDONEXPERIENCEWITHANOPERATINGETHERNETOF100NODESALONGAKILOMETEROFCOAXIALCABLEAMODELFORESTIMATINGPERFORMANCEUNDERHEAVYLOADSANDAPACKETPROTOCOLFORERRORCONTROLLEDCOMMUNICATIONAREINCLUDEDFORCOMPLETENESSKEYWORDSANDPHRASESCOMPUTERNETWORKS,PACKETSWITCHING,MULTIPROCESSING,DISTRIBUTEDCONTROL,DISTRIBUTEDCOMPUTING,BROADCASTCOMMUNICATION,STATISTICALARBITRATIONCRCATEGORIES381,432,635COPYRIGHT1976,ASSOCIATIONFORCOMPUTINGMACHINERY,INCGENERALPERMISSIONTOREPUBLISH,BUTNOTFORPROFIT,ALLORPARTOFTHISMATERIALISGRANTEDPROVIDEDTHATACMSCOPYRIGHTNOTICEISGIVENANDTHATREFERENCEISMADETOTHEPUBLICATION,TOITSDATEOFISSUE,ANDTOTHEFACTTHATREPRINTINGPRIVILEGESWEREGRANTEDBYPERMISSIONOFTHEASSOCIATIONFORCOMPUTINGMACHINERYAUTHORSPRESENTADDRESSESRMMETCALFE,TRANSACTIONTECHNOLOGY,INC,10880WILSHIREBOULEVARD,LOSANGELES,CA94304;DBOGGS,XEROXPALOALTORESEARCHCENTER,3333COYOTEHILLROAD,PALOALTO,CA943043951BACKGROUNDONECANCHARACTERIZEDISTRIBUTEDCOMPUTINGASASPECTRUMOFACTIVITIESVARYINGINTHEIRDEGREEOFDECENTRALIZATION,WITHONEEXTREMEBEINGREMOTECOMPUTERNETWORKINGANDTHEOTHEREXTREMEBEINGMULTIPROCESSINGREMOTECOMPUTERNETWORKINGISTHELOOSEINTERCONNECTIONOFPREVIOUSLYISOLATED,WIDELYSEPARATED,ANDRATHERLARGECOMPUTINGSYSTEMSMULTIPROCESSINGISTHECONSTRUCTIONOFPREVIOUSLYMONOLITHICANDSERIALCOMPUTINGSYSTEMSFROMINCREASINGLYNUMEROUSANDSMALLERPIECESCOMPUTINGINPARALLELNEARTHEMIDDLEOFTHISSPECTRUMISLOCALNETWORKING,THEINTERCONNECTIONOFCOMPUTERSTOGAINTHERESOURCESHARINGOFCOMPUTERNETWORKINGANDTHEPARALLELISMOFMULTIPROCESSINGTHESEPARATIONBETWEENCOMPUTERSANDTHEASSOCIATEDBITRATEOFTHEIRCOMMUNICATIONCANBEUSEDTODIVIDETHEDISTRIBUTEDCOMPUTINGSPECTRUMINTOBROADACTIVITIESTHEPRODUCTOFSEPARATIONANDBITRATE,NOWABOUT1GIGABITMETERPERSECOND1GBMPS,ISANINDICATIONOFTHELIMITOFCURRENTCOMMUNICATIONTECHNOLOGYANDCANBEEXPECTEDTOINCREASEWITHTIMEACTIVITYSEPARATIONBITRATEREMOTENETWORKS10KM1MBPSLOCALNETWORKS101KM110MBPSMULTIPROCESSORS1KM10MBPS11REMOTECOMPUTERNETWORKINGCOMPUTERNETWORKINGEVOLVEDFROMTELECOMMUNICATIONSTERMINALCOMPUTERCOMMUNICATION,WHERETHEOBJECTWASTOCONNECTREMOTETERMINALSTOACENTRALCOMPUTINGFACILITYASTHENEEDFORCOMPUTERCOMPUTERINTERCONNECTIONGREW,COMPUTERSTHEMSELVESWEREUSEDTOPROVIDECOMMUNICATION2,4,29COMMUNICATIONUSINGCOMPUTERSASPACKETSWITCHES1521,26ANDCOMMUNICATIONSAMONGCOMPUTERSFORRESOURCESHARINGI0,32WEREBOTHADVANCEDBYTHEDEVELOPMENTOFTHEARPACOMPUTERNETWORKTHEALOHANETWORKATTHEUNIVERSITYOFHAWAIIWASORIGINALLYDEVELOPEDTOAPPLYPACKETRADIOTECHNIQUESFORCOMMUNICATIONBETWEENACENTRALCOMPUTERANDITSTERMINALSSCATTEREDAMONGTHEHAWAIIANISLANDS1,2MANYOFTHETERMINALSARENOWMINICOMPUTERSCOMMUNICATINGAMONGTHEMSELVESUSINGTHEALOHANETWORKSMENEHUNEASAPACKETSWITCHTHEMENEHUNEANDANARPANETIMPARENOWCONNECTED,PROVIDINGTERMINALSONTHEALOHANETWORKACCESSTOCOMPUTINGRESOURCESONTHEUSMAINLANDJUSTASCOMPUTERNETWORKSHAVEGROWNACROSSCONTINENTSANDOCEANSTOINTERCONNECTMAJORCOMPUTINGFACILITIESAROUNDTHEWORLD,THEYARENOWGROWINGDOWNCORRIDORSANDBETWEENBUILDINGSTOINTERCONNECTMINICOMPUTERSINOFFICESANDLABORATORIES3,12,13,14,3512MULTIPROCESSINGMULTIPROCESSINGFIRSTTOOKTHEFORMOFCONNECTINGANI/OCONTROLLERTOALARGECENTRALCOMPUTER;RAMSASPISACOMMUAICATIONSJULY1976OFVOLUME19THEACMNUMBER7CLASSICEXAMPLE\29\NEXT,MULTIPLECENTRALPROCESSORSWERECONNECTEDTOACOMMONMEMORYTOPROVIDEMOREPOWERFORCOMPUTEBOUNDAPPLICATIONS\33\FORCERTAINOFTHESEAPPLICATIONS,MOREEXOTICMULTIPROCESSORARCHITECTURESSUCHASILLIAEIVWEREINTRODUCED\5\MORERECENTLYMINICOMPUTERSHAVEBEENCONNECTEDINMULTIPROCESSORCONFIGURATIONSFORECONOMY,RELIABILITY,ANDINCREASEDSYSTEMMODULARITY\24,36\THETRENDHASBEENTOWARDDECENTRALIZATIONFORRELIABILITY;LOOSELYCOUPLEDMULTIPROCESSORSYSTEMSDEPENDLESSONSHAREDCENTRALMEMORYANDMOREONTHINWIRESFORINTERPROCESSCOMMUNICATIONWITHINCREASEDCOMPONENTISOLATION\18,26\WITHTHECONTINUEDTHINNINGOFINTERPROCESSORCOMMUNICATIONFORRELIABILITYANDTHEDEVELOPMENTOFDISTRIBUTABLEAPPLICATIONS,MULTIPROCESSINGISGRADUALLYAPPROACHINGALOCALFORMOFDISTRIBUTEDCOMPUTING13LOCALCOMPUTERNETWORKINGETHERNETSHARESMANYOBJECTIVESWITHOTHERLOCALNETWORKSSUCHASMITRESMITRIX,BELLTELEPHONELABORATORYSSPIDER,ANDUCIRVINESDISTRIBUTEDCOMPUTINGSYSTEMDCS\12,13,14,35\PROTOTYPESOFALLFOURLOCALNETWORKINGSCHEMESOPERATEATBITRATESBETWEENONEANDTHREEMEGABITSPERSECONDMITRIXANDSPIDERHAVEACENTRALMINICOMPUTERFORSWITCHINGANDBANDWIDTHALLOCATION,WHILEDCSANDETHERNETUSEDISTRI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编号:201401051948286816    类型:共享资源    大小:1.05MB    格式:PDF    上传时间:2014-01-05
  
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