互联网络联网的基本原理-7_OSI开放系统互连(zslcn周生烈编译摘注评)

1啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊(fm.DocWikiCISCO/zslcn编译注)互联网络联网的基本原理-7_OSI(zslcn周生烈编译摘注评)七．OpenSystemInterconnectionProtocols开放系统互连协议关键词：物理层，数据链路层，网络层，传输层，会晤层，表示层，应用层:55七．OpenSystemInterconnectionProtocols开放系统互连协议FromDocWikiFromDocWiki从DocWikiJumpto:navigation,searchTheOpenSystemInterconnection(OSI)protocolsuiteiscomprisedofnumerousstandardprotocolsthatarebasedontheOSIreferencemodel.Theseprotocolsarepartofaninternationalprogramtodevelopdata-networkingprotocolsandotherstandardsthatfacilitatemultivendorequipmentinteroperability.TheOSIprogramgrewoutofaneedforinternationalnetworkingstandardsandisdesignedtofacilitatecommunicationbetweenhardwareandsoftwaresystemsdespitedifferencesinunderlyingarchitectures.开放系统互连（OSI）协议栈由许多标准协议组成,它们都基于OSI参考模型。这些协议是，一项国际安排,用来开发数据联网协议s,以及促进多厂商设备互操作性的其它标准s,的一部分。OSI的安排是出于一种对国际联网标准化的需要，设计成便于硬件系统和软件系统之间通信,而不管基础结构的差异。TheOSIspecificationswereconceivedandimplementedbytwointernationalstandardsorganizations:theInternationalOrganizationforStandardization(ISO)andtheInternationalTelecommunicationUnion-TelecommunicationsStandardsSector(ITU-T).ThisarticleprovidesasummaryoftheOSIprotocolsuiteandillustratesitsmappingtothegeneralOSIreferencemodel.指导目录联网技术手册指导目录Part1InternetworkingBasics互联网络联网基本原理Part2LANTechnologies局域网技术part3WANTechnologies广域网技术part4InternetProtocols互联网协议part5BridgingandSwitching桥接和交换part6Routing路由part7NetworkManagement网络管理part8Voice/DataIntegrationTechnologies声音/数据集成技术part9WirelessTechnologies无线技术part10CableAccessTechnologies有线接入技术part11Dial-upTechnology拨号技术part12SecurityTechnologies安全技术part13QualityofServiceNetworking联网服务质量part14NetworkCachingTechnologies网络缓存技术part15IBMNetworkManagementIBM网络管理part16MultiserviceAccessTechnologies多业务接入技术2OSI规范s是由两个国际标准化组织构思和组织实施的：国际标准化组织（ISO）和国际电信联盟电信标准化部（ITU-T）。本文提供了一个OSI协议栈的汇总,举例说明了它与一般OSI参考模型的映射关系。Contents[hide]1OSINetworkingProtocols1.1Figure:TheOSIProtocolSuiteMapstoAllLayersoftheOSIReferenceModel1.2OSIPhysicalandDataLinklayers1.3OSINetworkLayer1.3.1OSILayerStandards1.3.2OSIConnectionlessNetworkService1.3.3OSIConnection-OrientedNetworkService1.3.4NetworkLayerAddressing1.3.5OSIProtocolsTransportLayer1.3.6OSIProtocolsSessionLayer1.3.7OSIProtocolsPresentationLayer1.3.8OSIProtocolsApplicationLayer2ReviewQuestions目录[hide]1OSI网络协议1.1图：OSI协议参考模型套件映射到所有图层的OSI1.2OSI的物理和数据链路层1.3OSI网络层1.3.1OSI的层标准1.3.2OSI无连接网络服务1.3.3OSI的面向连接的网络服务1.3.4网络层寻址1.4传输层OSI协议1.5会话层OSI协议1.6表示层OSI协议1.7应用层OSI协议2ReviewQuestions2复习题1.OSINetworkingProtocolsFigure:TheOSIProtocolSuiteMapstoAllLayersoftheOSIReferenceModelillustratestheentireOSIprotocolsuiteanditsrelationtothelayersoftheOSIreferencemodel.Eachcomponentofthisprotocolsuiteisdiscussedbrieflyinthisarticle.图：OSI协议栈映射到OSI参考模型所有层说明了整个OSI协议栈,以及与OSI参考模型层的关系。该协议族的每个部分在本文中都作了简短的讨论。Figure:TheOSIProtocolSuiteMapstoAllLayersoftheOSIReferenceModel1.1图：OSI协议族映射到OSI参考模型的所有层31.2OSIPhysicalandDataLinklayersTheOSIprotocolsuitesupportsnumerousstandardmedia-accessprotocolsatthephysicalanddatalinklayers.Thewidevarietyofmedia-accessprotocolssupportedintheOSIprotocolsuiteallowsotherprotocolsuitestoexisteasilyalongsideOSIonthesamenetworkmedia.Supportedmedia-accessprotocolsincludeIEEE802.2LLC,IEEE802.3,TokenRing/IEEE802.5,FiberDistributedDataInterface(FDDI),andX.25.1.2OSI物理和数据链路层OSI协议族支持物理层和数据链路层上的多种标准媒体访问协议。在OSI协议栈中的大量媒体访问协议,允许其他多种协议与ISO一道,共存在同一个网络媒体上。所支持的媒体访问协议,包括IEEE802.2LLC,IEEE802.3,令牌环/IEEE802.5,光纤分布式数据接口（FDDI）和X.25。1.3OSINetworkLayerTheOSIprotocolsuitespecifiestworoutingprotocolsatthenetworklayer:EndSystem-to-IntermediateSystem(ES-IS)andIntermediateSystem-to-IntermediateSystem(IS-IS).Inaddition,theOSIsuiteimplementstwotypesofnetworkservices:connectionlessserviceandconnection-orientedservice.OSI网络层OSI协议栈在网络层上指定了两个路由协议：端系统到中间系统（ES-IS）和中间系统到中间系统（IS-IS）。此外，OSI栈实现了两类网络服务：无连接服务和面向连接服务。41.3.1OSILayerStandardsInadditiontothestandardsspecifyingtheOSInetworklayerprotocolsandservices,thefollowingdocumentsdescribeotherOSInetworklayerspecifications:1.3.1OSI的层标准s除了指定OSI网络层协议和服务的那些标准外，下列文档还描述了其他OSI网络层规范：ISO8648-Thisstandarddefinestheinternalorganizationofthenetworklayer(IONL),whichdividesthenetworklayerintothreedistinctsublayerstosupportdifferentsubnetworktypes.ISO8348-Thisstandarddefinesnetworklayeraddressinganddescribestheconnection-orientedandconnectionlessservicesprovidedbytheOSInetworklayer.ISOTR9575-Thisstandarddescribestheframework,concepts,andterminologyusedinrelationtoOSIroutingprotocols.ISO8648-此标准定义了网络层的内部机构（IONL），它将网络层分为三个明确的子层，以支持不同的子网类型。ISO8348-本标准规定了网络层寻址,并描述了为OSI网络层所提供的,面向连接和无连接的服务。ISOTR9575–本标准描述了用于与OSI路由协议s有关的框架，概念和术语1.3.2OSIConnectionlessNetworkServiceOSIconnectionlessnetworkserviceisimplementedbyusingtheConnectionlessNetworkProtocol(CLNP)andConnectionlessNetworkService(CLNS).CLNPandCLNSaredescribedintheISO8473standard.CLNPisanOSInetworklayerprotocolthatcarriesupper-layerdataanderrorindicationsoverconnectionlesslinks.CLNPprovidestheinterfacebetweentheConnectionlessNetworkService(CLNS)andupperlayers.CLNSprovidesnetworklayerservice