【英文标准名称】:Informationprocessingsystems-FibreDistributedDataInterface(FDDI)-Mediaaccesscontrol-2(MAC-2)
【原文标准名称】:信息处理系统.光纤分布式数据接口(FDDI).介质存取控制-2(MAC-2)
【标准号】:BSISO/IEC9314-8-1998
【标准状态】:现行
【国别】:英国
【发布日期】:1998-12-15
【实施或试行日期】:1998-12-15
【发布单位】:英国标准学会(GB-BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:纤维光学;数据传输方法;光纤分布数据接口(FIBERDISTRIBUTEDDATAINTERFACE);数据传输;开放系统互连;计算机网络;地址(数据处理);纤维光缆;语义学;信息交流;接口;权标环网;数据链路层;物理层(开放系统互连);光纤
【英文主题词】:Communicationprocedures;Controlprocedures;Datainterface;Dataprocessing;Datatransmission;Definition;Definitions;FDDI;Informationinterchange;Informationtechnology;Interfaces;Interfaces(dataprocessing);MAC;Networkinterconnection;Opticalfibres;Opticalwaveguides;Tokenring
【摘要】:ThispartofISO/IEC9314specifiestheMediaAccessControl(MAC),themiddlesublayeroftheDataLinkLayer(DLL),forFibreDistributedDataInterface(FDDI).FDDI(ISO/IEC9314)providesahigh-bandwidth(100Mbit/s),general-purposeinterconnectionamonginformationprocessingsystems,subsystemsandperipheralequipment,usingfibreopticsorothertransmissionmedia.FDDIcanbeconfiguredtosupportasustaineddatatransferrateofatleast80Mbit/s(10Mbyte/s).FDDIprovidesconnectivityformanynodesdistributedoverdistancesofmanykilometresinextent.CertaindefaultparametervaluesforFDDI(e.g.timersettings)arecalculatedonthebasisofupto1000transmissionlinksorupto200kmtotalfibrepathlength(typicallycorrespondingto500nodesand100kmofdualfibrecable,respectively);however,theFDDIprotocolscansupportmuchlargernetworksbyincreasingtheseparametervalues.Asshowninfigure1,ISO/IEC9314consistsofa)APhysicalLayer(PL),whichisdividedintotwosublayers:1)APhysicalMediumDependent(PMD),whichprovidesthedigitalbasebandpoint-to-pointcommunicationbetweennodesintheFDDInetwork.ThePMDprovidesallservicesnecessarytotransportasuitablycodeddigitalbitstreamfromnodetonode.ThePMDdefinesandcharacterizesthefibre-opticdriversandreceivers,medium-dependentcoderequirements,cables,connectors,powerbudgets,opticalbypassprovisions,andphysical-hardware-relatedcharacteristics.ItspecifiesthepointofinterconnectabilityforconformingFDDIattachments.TheinitialPMDstandard,ISO/IEC9314-3,definesattachmenttomulti-modefibre.AdditionalPMDsublayerstandardsarebeingdevelopedforattachmenttosingle-modefibreandSONET.2)APhysicalLayerProtocol(PHY),whichprovidesconnectionbetweenthePMDandtheDataLinkLayer.PHYestablishesclocksynchronizationwiththeupstreamcode-bitdatastreamanddecodesthisincomingcode-bitstreamintoanequivalentsymbolstreamforusebythehigherlayers.PHYprovidesencodinganddecodingbetweendataandcontrolindicatorsymbolsandcodebits,mediumconditioningandinitializing,thesynchronizationofincomingandoutgoingcode-bitclocks,andthedelineationofoctetboundariesasrequiredforthetransmissionofinformationtoorfromhigherlayers.InformationtobetransmittedonthemediumisencodedbythePHYusingagrouptransmissioncode.b)ADataLinkLayer(DLL),whichisdividedintotwoormoresublayers:1)AnoptionalHybridRingControl(HRC),whichprovidesmultiplexingofpacketandcircuitswitcheddataonthesharedFDDImedium.HRCcomprisestwointernalcomponents,aHybridMultiplexer(H-MUX)andanisochronousMAC(I-MAC).H-MUXmaintainsasynchronous125μscyclestructureandmultiplexesthepacketandcircuitswitcheddatastreams,andI-MACprovidesaccesstocircuitswitchedchannels.2)AMediaAccessControl(MAC),whichprovidesfairanddeterministicaccesstothemedium,addressrecognition,andgenerationandverificationofframechecksequences.Itsprimaryfunctionisthedeliveryofpacketdata,includingframegeneration,repetition,andremoval.ThedefinitionofMACiscontainedinthispartoflSO/IEC9314.3)AnoptionalLogicalLinkControl(LLC),whichprovidesacommonprotocolforanyrequiredpacketdataadaptationservicesbetweenMACandtheNetworkLayer.LLCisnotspecifiedbyFDDI.4)AnoptionalCircuitSwitchingMultiplexer(CS-MUX),whichprovidesacommonprotocolforanyrequiredcircuitdataadaptationservicesbetweenI-MACandtheNetworkLayer.CS-MUXisnotspecifiedbyFDDI.c)AStationManagement(SMT),whichprovidesthecontrolnecessaryatthenodeleveltomanagetheprocessesunderwayinthevariousFDDIlayerssuchthatanodemayworkcooperativelyonaring.SMTprovidesservicessuchascontrolofconfigurationmanagement,faultisolationandrecovery,a
【中国标准分类号】:L65
【国际标准分类号】:33_180_01;35_110
【页数】:108P.;A4
【正文语种】:英语
基本信息
标准名称: | 管路法兰用缠绕式垫片 |
中标分类: |
机械 >>
通用零部件 >>
管路附件 |
替代情况: | JB 90-1959 |
发布日期: | 1994-12-09 |
实施日期: | 1995-10-01 |
首发日期: | 1900-01-01 |
作废日期: | 1900-01-01 |
归口单位: | 机械工业部机械标准化研究所 |
出版日期: | 1900-01-01 |
页数: | 4 页 |
批文号: | 机械科[1994]1018号 |
适用范围
本标准代替JB 90-59。
前言
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目录
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引用标准
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所属分类: 机械 通用零部件 管路附件