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【英文标准名称】:Informationtechnology-FibreDistributedDataInterface(FDDI)-Part9:Low-costfibrephysicallayermediumdependent(LCF-PMD)
【原文标准名称】:信息技术光纤分布式数据接口(FDDI)第9部分:低价光纤物理层相关媒体(LCF-PMD)
【标准号】:ISO/IEC9314-9-2000
【标准状态】:现行
【国别】:国际
【发布日期】:2000-06
【实施或试行日期】:
【发布单位】:国际标准化组织(IX-ISO)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:
【英文主题词】:Communicationprocedures;Controlprocedures;Datainterface;Dataprocessing;Datatransmission;FDDI;Fibredistributeddatainterface;Informationinterchange;Informationtechnology;Interfaces;Interfaces(dataprocessing);Networkinterconnection;Opticalfibr
【摘要】:ThispartofISO/IEC9314specifiestherequirementsfortheFibreDistributedDataInterface(FDDI);tokenringlow-costfibrephysicallayermediumdependent(LCF-PMD).FDDIprovidesahigh-bandwidth(100Mbit/s),general-purposeinterconnectionamongcomputersandperipheralequipmentusingfibreopticsastheprimarytransmissionmedium.FDDIcanbeconfiguredtosupportasustaineddatatransferrateofatleast80Mbit/s(10Mbyte/s).FDDIprovidesconnectivityformanynodesdistributedoverdistancesofseveralkilometersinextent.DefaultvaluesforFDDIarecalculatedonthebasisof1000physicallinksandatotalfibrepathlengthof200km(typicallycorrespondingto500nodesand100kmofdualfibrecable).FDDIconsistsof:a)aPhysicalLayer(PL),whichisdividedintotwosublayers1)APhysicalLayer,MediumDependent(PMD)sublayer(ISO/IEC9314-3),withseveralalternativemediumchoices,whichprovidesthedigitalbasebandpoint-to-pointcommunicationbetweennodesintheFDDInetwork.ThePMDprovidesallservicesnecessarytotransportasuitablycodeddigitalbitstreamfromnodetonode.ThePMDdefinesandcharacterizesthemediumdriversandreceivers,medium-dependentcoderequirements,cables,connectors,powerbudgets,opticalbypassprovisions,andphysical-hardware-relatedcharacteristics.ItspecifiesthepointofinterconnectabilityforconformingFDDIattachments.TheoriginalPMDstandard(ISO/IEC9314-3),calledPMD,definesattachmenttomulti-modefibreupto2km,whilethisLCF-PMD,opticallyinteroperablewiththeoriginalPMD,defineslow-costattachmentstomulti-modefibreupto500m.AdditionalPMDsublayerstandardsareforattachmenttosinglemodefibre(SMF-PMD),andtwisted-pairupto100m(TP-PMD);2)APhysicalLayerProtocol(PHY)sublayer(ISO/IEC9314-1),anditsenhancement,(PHY-2),whichprovidesconnectionbetweenthePMDandtheDataLinkLayer.PHYestablishesclocksynchronizationwiththeupstreamcode-bitdatastreamanddecodesthisincomingcode-bitstreamintoanequivalentsymbolstreamforusebythehigherlayers.PHYprovidesencodinganddecodingbetweendataandcontrolindicatorsymbolsandcodebits,mediumconditioningandinitializing,thesynchronizationofincomingandoutgoingcode-bitclocks,andthedelineationofoctetboundariesasrequiredforthetransmissionofinformationtoorfromhigherlayers.InformationtobetransmittedonthemediumisencodedbythePHYusingagrouptransmissioncode;b)aDataLinkLayer(DLL),whichisdividedintotwoormoresublayers1)AnoptionalHybridRingControl(HRC)(ISO/IEC9314-5),whichprovidesmultiplexingofpacketandcircuitswitcheddataonthesharedFDDImedium.HRCcomprisestwointernalcomponents,aHybridMultiplexer(H-MUX)andanIsochronousMAC(I-MAC).H-MUXmaintainsasynchronous125μscyclestructureandmultiplexesthepacketandcircuitswitcheddatastreams,andI-MACprovidesaccesstocircuitswitchedchannels;2)AMediaAccessControl(MAC)(ISO/IEC9314-2),anditsenhancement(MAC-2),whichprovidesfairanddeterministicaccesstothemedium,addressrecognition,andgenerationandverificationofframechecksequences.Itsprimaryfunctionisthedeliveryofpacketdata,includingframegeneration,repetition,andremoval;3)AnoptionalLogicalLinkControl(LLC),whichprovidesacommonprotocolforanyrequiredpacketdataadaptationservicesbetweenMACandtheNetworkLayer.LLCisnotspecifiedbyFDDI;4)AnoptionalCircuitSwitchingMultiplexer(CS-MUX),whichprovidesacommonprotocolforanyrequiredcircuitdataadaptationservicesbetweenI-MACandtheNetworkLayer.CS-MUXisnotspecifiedbyFDDI;c)aStationManagement(SMT),whichprovidesthecontrolnecessaryatthenodeleveltomanagetheprocessesunderwayinthevariousFDDIlayerssuchthatanodemayworkcooperativelyonaring.SMTprovidesservicessuchascon
【中国标准分类号】:M33
【国际标准分类号】:33_180_01;33_180_10;35_100_10;35_110
【页数】:48P.;A4
【正文语种】:英语