OTN学习笔记1-5-完整版

OTN学习笔记1、Theopticaltransporthierarchy(OTH)supportstheoperationandmanagementaspectsofopticalnetworksofvariousarchitectures,e.g.,point-to-point,ringandmesharchitectures.ThisRecommendationdefinestheinterfacesoftheopticaltransportnetworktobeusedwithinandbetweensubnetworksoftheopticalnetwork,intermsof:–opticaltransporthierarchy(OTH);–functionalityoftheoverheadinsupportofmulti-wavelengthopticalnetworks;–framestructures;–bitrates;–formatsformappingclientsignals.光传送序列（OTH）支持各种体系结构（即点对点、环形和网孔形体系结构）光网络的运行和管理。依据光传送序列（OTH）、多波长光网络支持中的开销功能、帧结构比特率及映射客户信号的方式，本建议定义了光传送网络的接口，以便将这些接口用于光网络的子网内部和子网之间。2、opticaltransportmodule(OTM-n.m):TheOTMistheinformationstructurethatistransportedacrossanONNI.Theindexnandmdefinethenumberofsupportedwavelengthsandbitratesattheinterface.TwoOTMstructuresaredefined:TheOTMwithfullfunctionality(OTM-n.m)istheinformationstructureusedtosupportopticaltransmissionsection(OTS)layerconnectionsintheOTN.Thecharacteristicinformationoftheopticaltransmissionsectionlayer(OTS_CI)consistsofinformationpayload(OTS_CI_PLD)andopticaltransmissionsectionoverheadinformationfields(OTS_CI_OH).Theopticaltransmissionsectionoverhead(OTS_OH)informationfieldsarecontainedwithintheOTMoverheadsignal(OOS)informationstructure.TheOTM-n.mconsistsofuptonmultiplexedopticalchannelsandanOTMoverheadsignaltosupportthenon-associatedoverhead.TheOTMwithreducedfunctionality(OTM-nr.m/OTM-0)istheinformationstructureusedtosupportopticalphysicalsection(OPS)layerconnectionsintheOTN.Thecharacteristicinformationoftheopticalphysicalsectionlayer(OPS_CI)consistsofinformationpayload(OPS_CI_PLD).OTM-0consistsofasingleopticalchannelwithoutaspecificcolourassigned.TheOTM-nr.mconsistsofuptonmultiplexedopticalchannels.Non-associatedoverheadisnotsupported光传送模块（OTM）：OTM是穿越ONNI传送的信息结构。n和m定义了接口支持的波长数量和比特率。定义了两种OTM：完全功能OTM（OTM-n.m）和简化功能OTM（OTM-0和OTM-nr.m）。完全功能OTM（OTM-n.m）是用于支持OTN中光传输段（OTS）层连接的信息结构。光传输段层的特征信息（OTS_CI）由信息净荷（OTS_CI_PLD）和光传输段开销信息（OTS_CI_OH）组成。光传输段开销（OTS_OH）信息包含在OTM开销信号（OOS）信息结构中。为了支持非联合开销，完全功能OTM-n.m由最多n个复用的光信道和一个OTM开销构成。简化功能OTM（OTM-nr.m/OTM-0）是用于支持OTN中光物理段（OPS）层连接的信息结构。光物理段层的特征信息（OPS_CI）由信息净荷（OPS_CI_PLD）组成。OTM-0由不具有分配特定颜色的单个光信道构成。OTM-nr.m最多由n个复用光信道组成。不支持非联合开销。3、opticalchannel(OCh[r]):TheOChistheinformationstructureusedtosupporttheOChtrail.TwoOChstructuresaredefined.TheOChclientsignalsdefinedinthisRecommendationaretheOTUksignals.Otherdigitalclientsignals(e.g.,STM-n,GbE)maybesupportedbytheOTM.Opticalchannelwithfullfunctionality(OCh):TheOChisaninformationstructureconsistingoftheinformationpayload(OCh_PLD)withacertainbandwidthandnon-associatedoverhead(OCh_OH)formanagementoftheopticalchannel.Opticalchannelwithreducedfunctionality(OChr):TheOChrisaninformationstructureconsistingoftheinformationpayload(OCh_PLD)withacertainbandwidth.Non-associatedoverheadisnotsupported.光信道（OCh）：OCh是用于支持OCh踪迹的信号结构。定义了两种结构的OCh。本建议中定义的OCh客户信号为OTUk信号。可以通过OTM支持其他数字客户信号（即STM-n和GbE）。完全功能光信道（OCh）：为了管理光信道，OCh是一种由具有特定带宽和非联合开销（OCh_OH）的、信息净荷（OCh_PLD）组成的信息结构。简化功能光信道（OChr）：OChr是一种由具有特定带宽的、信息净荷组成的信息结构。不支持非联合开销。4、opticalchanneltransportunit(OTUk[V]):TheOTUkistheinformationstructureusedfortransportofanODUkoveroneormoreopticalchannelconnections.ItconsistsoftheopticalchanneldataunitandOTUkrelatedoverhead(FECandoverheadformanagementofanopticalchannelconnection).Itischaracterizedbyitsframestructure,bitrate,andbandwidth.TwoversionsoftheOTUkaredefined:CompletelystandardizedOTUk(OTUk):ThecompletelystandardizedOTUkisusedonOTMIrDIsandmaybeusedonOTMIaDIs.FunctionallystandardizedOTUk(OTUkV):ThepartlystandardizedOTUkisusedonOTMIaDIs.光信道传送单元（OTUk）：OTUk是为了在一个或多个光信道连接上进行光信道数据单元（ODUk）传送的信息结构。它由ODUk和OTUk相关开销（用于光信道连接的FEC和开销）组成。它由其帧结构、比特率及带宽规范。定义了两种版本的OTUk。完全标准化OTUk（OTUk）：完全标准化OTUk可以用于OTMIrDIs和OTMIaDIs。功能标准化OTUk（OTUkV）：部分标准化OTUk用于OTMIaDIs。5、opticalchannelpayloadunit(OPUk):TheOPUkistheinformationstructureusedtoadaptclientinformationfortransportoveranopticalchannel.ItcomprisesclientinformationtogetherwithanyoverheadneededtoperformrateadaptationbetweentheclientsignalrateandtheOPUkpayloadrateandotherOPUkoverheadsupportingtheclientsignaltransport.Thisoverheadisadaptationspecific.光信道净荷单元（OPUk）：OPUk是为了用于在一个光信道中传送适配客户信息的信息结构。它由客户信息与需要在客户信号比特率与OPUk比特率之间完成速率适配的任何开销和支持客户信号传送的其他OPUk开销一起组成。该开销是适配特定的。6、opticalmultiplexunit(OMU-n,n≥1):TheOMU-nistheinformationstructureusedtosupportopticalmultiplexsection(OMS)layerconnectionsintheOTN.Thecharacteristicinformationoftheopticalmultiplexsectionlayer(OMS_CI)consistsofinformationpayload(OMS_CI_PLD)andopticalmultiplexsectionoverheadinformationfields(OMS_CI_OH).TheOMS_CI_PLDconsistsoftheOCG-npayload.TheOMS_CI_OHconsistsoftheOCG-noverheadandOMSspecificoverheadandistransportedwithintheOOSinformationstructure.TheorderoftheOMUisdefinedbytheorderoftheOCGthatitsupports光复用单元（OMU-n,n≥1）：OMU-n是用于在OTN中支持光复用段（OMS）层连接的信息结构。光复用段层的特定信息（OMS_CI）由信息净荷（OMS_CI_PLD）和光复用段开销信息（OMS_CI_OH）组成。OMS_CI_PLD由OCG-n净荷组成。OMS_CI_OH由OCG-n开销和OMS特定开销组成，并且在一个OOS信息结构中传送。OMU的阶数支持的OCG阶数决定。7、opticaltransportnetworknodeinterface(ONNI):Theinterfaceatanopticaltransportnetworknodewhichisusedtointerconnectwithanotheropticaltransportnetworknode.光传送网络节点接口（ONNI）：用于与其他光传送网络节点连接的、在光传送网络节点处的接口。8、OTMoverheadsignal(OOS):TheOOSistheinformationstructureusedfortransportofOTMnon-associatedoverheadovertheopticalsupervisorychannel.Thenon-associatedoverheadconsistsoftheopticaltransmissionsectionoverhead,opticalmultiplexsectionoverheadandopticalchannelnon-associatedoverhead.Itischaracterizedbyitsframestructure,bitrateandbandwidth.OTM开销信号（OOS）：OOS是用于在光监控信道上进行OTM非联合开销传送的信息结构。非联合开销由光传输段开销、光复用段开销和光信道非联合开销组成。它由其帧结构、比特率及带宽规范。9、opticalsupervisorychannel(OSC):ThephysicalcarrieroutsideoftheamplifierbandthatprovidestransportoftheOTMoverheadsignal.光信道监控信道（OSC）：提供OTM开销信号传送的放大器带外物理载波。10、OTUk,ODUkandOPUkoverheadassignment:Theassignmentofoverheadintheopticalchanneltransport/data/payloadunitsignaltoeachpartisdefinedinFigure5-1.OTUk、ODUk和OPUk开销分配：光信道传送/数据/净荷单元信号到每一部分中的开销分配如下。图5.111、OpticaltransportnetworkinterfacestructureTheopticaltransportnetworkasspecifiedinITU-TRec.G.872definestwointerfaceclasses:-Inter-domaininterface(IrDI);-Intra-domaininterface(IaDI).ThebasicsignalstructureisshowninFigure6-1.光传送网络接口结构ITU-TG.872建议中规范的光传送网络定义了两种接口类型：域间接口（IrDI）和域内接口（IaDI）。图6.112、opticaltransportnetwork（OTN）:atransportnetworkboundedbyopticalchannelaccesspoints.AnOpticalTransportNetwork(OTN)iscomposedofasetofOpticalNetworkElementsconnectedbyopticalfibrelinks,abletoprovidefunctionalityoftransport,multiplexing,routing,management,supervisionandsurvivabilityofopticalchannelscarryingclientsignals,accordingtotherequirementsgiveninITU-TG.872.光传送网络（OTN）：一种由光信道接入点约束的传送网络。根据ITU-TG.872建议给定的要求，OTN由一组通过光纤链路连接的、能够提供携带客户信号的传送、复用、路由发现、管理功能、监控和生存性功能的光网元组成。13、accesspoint（AP）:A"referencepoint"thatconsistsofthepairofco-located"unidirectionalaccess"points,andthereforerepresentsthebindingbetweenthetrailterminationandadaptationfunctions接入点（AP）：由一对共点“单向接入”点组成的“参考点”。所以，接入点代表踪迹终结和适配功能之间的绑定关系。OTN学习笔记214、ODUkpath(ODUkP):Theopticalchanneldataunitkpath(ODUkP)istheinformationstructureusedtosupporttheend-to-endODUktrail.ODUk通道（ODUkP）：ODUkP是用于支持端到端ODUk踪迹的信息结构。15、ODUkTCM(ODUkT):TheopticalchanneldataunitkTCM(ODUkT)istheinformationstructureusedtosupporttheTCMtrails.Upto6TCMsublayersaresupported.ODUkTCM（ODUkT）：ODUkT是用于支持TCM踪迹的信息结构。最多可以支持6个TCM子层。16、opticalchannelcarrier(OCC[r]):TheopticalchannelcarrierrepresentsatributaryslotwithintheOTM-n.TwoOCCstructuresaredefined:OCCwithfullfunctionality(OCC):TheOCCconsistsoftheOCCPayload(OCCp)andOCCOverhead(OCCo).TheOCCpcarriestheOCh_CI_PLDandisassignedtoawavelength/frequencyslotoftheWDMgroup.TheOCCocarriestheOCh_CI_OHandistransportedwithintheOOSinformationstructure.OCCwithreducedfunctionality(OCCr):TheOCCconsistsoftheOCCPayload(OCCp).TheOCCpcarriestheOCh_CI_PLDandisassignedtoawavelength/frequencyslotoftheWDMgroup.Non-associatedoverheadisnotsupported.光信道载波（OCC）：OCC表示OTM-n中的支路时隙。定义了两种结构的OCC：完全功能OCC（OCC）：OCC由OCC净荷（OCCp）和OCC开销（OCCo）组成。OCCp携带OCh_CI_PLD，并且被安排在WDM组的一个波长/频率位置。OCCo携带OCh_CI_OH，并且在OOS信息结构中传送。简化功能OCC（OCCr）：OCCr由OCCp组成。OCCp携带OCh_CI_PLD，并且被安排在WDM组的一个波长/频率位置。不支持非联合开销。18、opticalcarriergroupofordern(OCG-n[r]):nopticalchannelcarriersoccupyingfixed,definedpositionsinanOTMpayloadaretermedanopticalcarriergroup(OCG[r]).TwoOCGstructuresaredefined:OCGwithfullfunctionality(OCG-n):TheOCG-nconsistsofuptonOCCpayload(OCCp)andOCCOverhead(OCCo).OCGwithreducedfunctionality(OCG-nr):TheOCG-nrconsistsofuptonOCCpayload(OCCp).Non-associatedoverheadisnotsupportedn阶光载波组（OCG-n）：在OTM净荷中占据固定、限定位置的n个光信道载波是用于描述光载波组的术语。定义了两种结构的OCG：完全功能OCG（OCG-n）：OCG-n由最多n个OCCp和OCCo组成。简化功能OCG（OCG-nr）：OCG-nr由最多n个OCCp组成。不支持非联合开销。19、opticalphysicalsectionofordern(OPSn):alayernetworkthatprovidesfunctionalityfortransmissionofamulti-wavelengthopticalsignalonopticalmediaofvarioustypes(e.g.,G.652,G.653andG.655fibre).Notethata"multi-wavelength"signalincludesthecaseofjustoneopticalchannel.ItcombinesthetransportfunctionalityoftheOMSandOTSlayernetworkswithouttheirsupervisoryinformation.OPSncapacitiesforn=0andn=16aredefined.n阶OPS（OPSn）：为各种类型光介质（即G.652、G.653和G.655光纤）提供多波长光信号传输功能的层网络。注意：这里的“多波长”信号包括一个光信道的情况。它将OMS和OTS层网络的传送功能，并且不包括它们的监控信息。定义了n=0和n=16的OPSn容量。20、TheinformationstructurefortheOTNinterfacesisrepresentedbyinformationcontainmentrelationshipsandflows.TheprincipalinformationcontainmentrelationshipsaredescribedinFigures6-2,6-3and6-4.TheinformationflowsareillustratedinFigure6-5.ForsupervisionpurposesintheOTN,theOTUk/OTUkVsignalisterminatedwhenevertheOChsignalisterminated.OTN接口的信息结构由基本信息包含关系和信息流表示。在图6-2、6-3和6-4中描述了这种基本信息包含关系。在图6-5中，描述了相应的信息流。图6-2OTM-n.m基本信息包含关系图6-3OTM-0.m基本信息包含关系图6-4OTM-nr.m基本信息包含关系图6-5信息流关系举例（略）21、Figure7-1showstherelationshipbetweenvariousinformationstructureelementsandillustratesthemultiplexingstructureandmappings(includingwavelengthandtimedivisionmultiplexing)fortheOTM-n.图7-1表示各种信息结构之间的关系，并且也表明了OTM-n的复用结构和映射结构（包括波长和时分复用）。图7-1（1）图7-1左上部分图7-1（2）图7-1左中部分图7-1（2）图7-1左下部分图7-1（3）图7-1中间部分图7-1（4）图7-1右半部分我理解的OTN大概是这样的：第一步，将客户光信号变成电信号；第二步，形成OPUk信号；第三步，形成ODUk信号；第四步，形成OTUk信号；第五步，形成OCh或OChr信号；第六步，由OCh形成（实际是复用）OMSn或由OChr形成OPSn信号（并且以OTM-0.m或OTM-0形式传送），并且完成电光变换（这一步有疑问，需要继续学习）；第七步，由OMSn信号形成OISn信号（并且以OTM-n.m形式传送）。OTN学习笔记4：36、Theopticalchannelwithfullfunctionality(OCh)structureisconceptuallyshowninFigure10-1.Itcontainstwoparts:OChoverheadandOChpayload完全功能光信道（OCh）结构概念性地示于图10-1中。它包含两个部分：OCh开销和OCh净荷。37、Theopticalchannelwithreducedfunctionality(OChr)structureisconceptuallyshowninFigure10-2.Itcontains:OChrpayload.简化功能光信道（OChr）结构概念性地示于图10-2中。它包含OCh净荷。38、TheOTUk[V]conditionstheODUkfortransportoveranopticalchannelnetworkconnection.TheOTUkframestructureiscompletelystandardized.TheOTUkVisaframestructurethatisonlyfunctionallystandardized(i.e.,onlytherequiredfunctionalityisspecified).ThecompletelystandardizedOTUkframestructureasdefinedinthisRecommendationisshowninFigureII.1.OTUkVwiththesameoverheadbyteallocationastheOTUk,butuseofanalternativeFECasshowninFigureII.2.OTUkVwiththesameoverheadbyteallocationastheOTUk,butuseofasmaller,alternativeFECcodeandtheremainderoftheOTUkVFECoverheadareafilledwithfixedstuffasshowninFigureII.3.OTUkVwithalargerFECoverheadbyteallocationastheOTUk,anduseofanalternativeFECasshowninFigureII.4.OTUkVwithnooverheadbyteallocationforFECasshowninFigureII.5.OTUkVwithadifferentframestructurethantheOTUkframestructure,supportingadifferentOTUoverhead(OTUkVoverheadandOTUkVFEC)asshowninFigureII.6.OTUkVwithadifferentframestructurethantheOTUkframestructure,supportingadifferentOTUoverhead(OTUkVoverhead)andwithnooverheadbyteallocationforFECasshowninFigureII.7.OTUk[V]为使ODUk在光信道网络连接上传送提供条件。OTUk帧结构完全标准化。OTUkV是一个功能标准化的帧结构（即仅仅规范了要求的功能）。在本建议做定义了完全功能OTUk，如图Ⅱ.1。具有与OTUk相同开销字节分配的、应用交替FEC的OTUkV帧结构如图Ⅱ.2。具有与OTUk相同开销字节分配的、应用较小、交替FEC编码和由固定字节填充的OTUkVFEC开销区余部的OTUkV帧结构如图Ⅱ.3。具有象OTUk一样的较大FEC开销字节分配的、应用应用交替FEC的OTUkV帧结构如图Ⅱ.4。没有FEC开销字节分配的OTUk，如图Ⅱ.5。具有与OTUk帧结构不同的、支持不同OUT开销（OTUkV开销和FEC开销）的OTUkV，如图Ⅱ.6。具有与OTUk帧结构不同的、支持不同OUT开销（OTUkV开销）和没有FEC开销字节分配的OTUkV，如图Ⅱ.7。39、TheOTUksignalmusthavesufficientbittimingcontentattheONNI.Asuitablebitpattern,whichpreventsalongsequenceof"1"sor"0"s,isprovidedbyusingascrambler.Theoperationofthescramblershallbefunctionallyidenticaltothatofaframesynchronousscramblerofsequencelength65535operatingattheOTUkrate.Thegeneratingpolynomialshallbe1+x+x3+x12+x16.Figure11-3showsafunctionaldiagramoftheframesynchronousscrambler.Thescramblershallberesetto"FFFF"(HEX)onthemostsignificantbitofthebytefollowingthelastframingbyteintheOTUkframe,i.e.,theMSBoftheMFASbyte.Thisbit,andallsubsequentbitstobescrambled,shallbeaddedmodulo2totheoutputfromthex16positionofthescrambler.ThescramblershallruncontinuouslythroughoutthecompleteOTUkframe.Theframingbytes(FAS)oftheOTUkoverheadshallnotbescrambled.ScramblingisperformedafterFECcomputationandinsertionintotheOTUksignal.在ONNI处，OTUk必须具有丰富的定时比特信息。通过应用扰码器，提供表示为长“1”或“0”序列的合适比特图案。在功能上，扰码器的运行应该与工作在OTUk速率的、序列长度为65535的帧同步扰码器相同。生成多项式应该是1+x+x3+x12+x16。图11-3给出了同步扰码器的功能图。在OTUk帧结构中，在跟随最后成帧字节后字节的最有效比特（即MFAS字节的MSB）时扰码器应该复位为“FFFF”（16进制）。该比特及所有被扰码的序列比特应该与扰码器x16位置的输出模二加。扰码器应该连续运行输出全部OTUk帧。OTUk开销的成帧字节（FAS）应该不扰码。应该在FEC计算和插入到OTUk信号后进行扰码。40、TheODUk(k=1,2,3)framestructureisshowninFigure12-1.Itisorganizedinanoctet-basedblockframestructurewithfourrowsand3824columns.ThetwomainareasoftheODUkframeare:-ODUkoverheadarea;-OPUkarea.Columns1to14oftheODUkarededicatedtoODUkoverheadarea.ODUk（k=1,2,3）帧结构示于图12-1。它被安排成4行和3824列的块状帧结构。ODUk帧的两个主要区域为ODUk开销区域和OPUk区域。ODUk的的第1到第14列为ODUk开销区域。41、TheOPUk(k=1,2,3)framestructureisshowninFigure13-1.Itisorganizedinanoctet-basedblockframestructurewithfourrowsand3810columns.ThetwomainareasoftheOPUkframeare:-OPUkoverheadarea;-OPUkpayloadarea.Columns15to16oftheOPUkarededicatedtoOPUkoverheadarea.Columns17to3824oftheOPUkarededicatedtoOPUkpayloadarea.OPUk（k=1,2,3）帧结构示于图13-1。它被安排成4行和3810列的块状帧结构。OPUk帧的两个主要区域为OPUk开销区域和OPUk净荷区域。OPUk的的第15到第16列为OPUk开销区域。OPUk的的第17到第3824列为OPUk净荷区域。42、TheOTMoverheadsignal(OOS)consistsoftheOTS,OMSandOChoverhead.Theformat,structureandbitrateoftheOOSisnotdefinedinthisRecommendation.TheOOSistransportedviaanOSC.Dependingonanoperator'slogicalmanagementoverlaynetworkdesign,generalmanagementcommunicationsmayalsobetransportedwithintheOOS.Therefore,theOOSforsomeapplicationsmayalsotransportgeneralmanagementcommunications.Generalmanagementcommunicationsmayincludesignalling,voice/voicebandcommunications,softwaredownload,operator-specificcommunications,etcOTM开销信号（OOS）由OTS、OMS和OCh开销组成。OOS的形式、结构和比特率不在本建议中定义。OOS通过OSC传送。与涉及网络设计的操作人员逻辑管理有关的，通用管理通信可以在OOS中传送。所以，一些应用的OOS也可以传送通用管理通信。通用管理通信可能包括信令、语音/语音频带通信、软件下载、操作者特定通信等。OTN学习笔记543、AnoverviewofOTS,OMSandOChoverheadispresentedinFigure15-1.AnoverviewofOTUk,ODUkandOPUkoverheadispresentedinFigures15-2and15-3.OTS、OMS和OCh开销示于图15-1。OTUk、ODUk和OPUk示于图15-2和15-3。44、OPUkOHinformationisaddedtotheOPUkinformationpayloadtocreateanOPUk.Itincludesinformationtosupporttheadaptationofclientsignals.TheOPUkOHisterminatedwheretheOPUkisassembledanddisassembled.TheOPUkoverheadconsistsof:payloadstructureidentifier(PSI)includingthepayloadtype(PT),overheadassociatedwithconcatenationandoverhead(e.g.,justificationcontrolandopportunitybits)associatedwiththemappingofclientsignalsintotheOPUkpayload.TheOPUkPSIandPToverheadlocationsareshowninFigure15-23.OnebyteisallocatedintheOPUkoverheadtotransporta256-bytepayloadstructureidentifier(PSI)signal.Thebyteislocatedinrow4,column15oftheOPUkoverhead.Aone-bytepayloadtypesignalisdefinedinthePSI[0]byteofthepayloadstructureidentifiertoindicatethecompositionoftheOPUksignal.SevenbytesarereservedintheOPUkoverheadformappingandconcatenationspecificoverhead.OPUkmappingspecificoverheadarelocatedinrows1to3,columns15and16andcolumn16row4.Inaddition,255bytesinthePSIarereservedformappingandconcatenationspecificpurposes.Theuseofthesebytesdependsonthespecificclientsignalmapping.将OPUkOH信息加入到OPUk信息净荷上以创建一个OPUk。它包括支持客户信号适配的信息。在建立和分解OPUk的地方，要终结OPUkOH。OPUkOH由包括净荷类型（PT）的净荷结构指示符（PSI）、具有级联有关的开销及与客户信号适配成OPUk净荷有关的开销（调整控制和调整机会比特）组成。OPUkPSI和PT的位置示于图15-23。为了传送一个256字节净荷结构指示符（PSI）信号，在OPUk中定义了1个字节。该字节定位于OPUk开销的第4行和第15列。为了指示OPUk信号的补偿，单字节净荷类型在净荷结构指示符的PSI[0]字节定义。在OPUk开销中预留7个字节用于映射和级联特定开销。OPUk映射特定开销定位在第1到第3行和第15到第16列、第4行和第16列。此外，在PSI中预留255字节用于映射和级联特定开销。这些字节的应用与特定客户映射有关。45、ODUkOHinformationisaddedtotheODUkinformationpayloadtocreateanODUk.Itincludesinformationformaintenanceandoperationalfunctionstosupportopticalchannels.TheODUkOHconsistsofportionsdedicatedtotheend-to-endODUkpathandtosixlevelsoftandemconnectionmonitoring.TheODUkpathOHisterminatedwheretheODUkisassembledanddisassembled.TheTCOHisaddedandterminatedatthesourceandsinkofthecorrespondingtandemconnections,respectively.将ODUkOH加入到ODUk信息净荷，以便形成一个ODUk。它包括支持光信道的维护和操作功能信息。ODUkOH由专用端到端ODUk通道和六级级联监视组成。ODUk通道OH在ODUk接入和接出的地方终结。TCOH（级联开销）分别在相关级联连接的源和宿处被加入和终结。46、OTUkOHinformationispartoftheOTUksignalstructure.Itincludesinformationforoperationalfunctionstosupportthetransportviaoneormoreopticalchannelconnections.TheOTUkOHisterminatedwheretheOTUksignalisassembledanddisassembled.OTUkOH信息是OTUk信号结构的一部分。它包括通过一个或多个光信道连接支持传送的操作功能信息。OTUkOH在OTUk信号接入和接出的地方被终结。47、OChOHinformationisaddedtotheOTUktocreateanOCh.Itincludesinformationformaintenancefunctionstosupportfaultmanagement.TheOChOHisterminatedwheretheOChsignalisassembledanddisassembled.OChOH信息被加入到OTUk，以便创建一个OCh。它包括用于支持故障管理的维护功能的信息。OChOH在OCh信号接入和接出的地方被终结。48、OMSOHinformationisaddedtotheOCGtocreateanOMU.Itincludesinformationformaintenanceandoperationalfunctionstosupportopticalmultiplexsections.TheOMSOHisterminatedwheretheOMUisassembledanddisassembled.OMSOH信息被加入到OCG，以便创建一个OMU。它包括用于支持光复用段维护和操作功能的信息。OMSOH在OMU信号接入和接出的地方被终结。49、OTSOHinformationisaddedtotheinformationpayloadtocreateanOTM.Itincludesinformationformaintenanceandoperationalfunctionstosupportopticaltransmissionsections.TheOTSOHisterminatedwheretheOTMisassembledanddisassembled.OTSOH信息被加入到信息净荷，以便创建一个OTM。它包括用于支持光传输段维护和操作功能的信息。OTSOH在OTM信号接入和接出的地方被终结。50、COMMSOHinformationisaddedtotheinformationpayloadtocreateanOTM.Itprovidesgeneralmanagementcommunicationbetweennetworkelements.COMMSOH信息被加入到信息净荷，以便创建一个OTM。它在网元之间提供一般的管理通信。51、ntenancesignalsincludeOTSmaintenancesignals(OTS-PMI),OMSmaintenancesignals(OMS-FDI-P,OMS-FDI-OandOMS-PMI),OChmaintenancesignals(OCh-FDI-P,OCh-FDI-OandOCh-OCI),OTUkmaintenancesignals(OTUk-AIS),ODUkmaintenancesignals(ODUk-AIS,ODUk-OCIandODUk-LCK)andClientmaintenancesignal.OTS-PMIisgeneratedasanindicationthattheOTSpayloaddoesnotcontainanopticalsignal.OMS-FDI-PisgeneratedasanindicationofanOMSserverlayerdefectintheOTSnetworklayer.OMS-FDI-Oisgeneratedasani