OTN原理及关键技术

PrincipleandKeyTechnologiesofOTNPage2

Chapter1BackgroundandConceptofOTNContentsChapter2

Hierarchy

ofOTNChapter3G.709IntroductionChapter4

OTNkeyTechnologiesChapter5ReviewandOutlook

Page3

Chapter1Background&ConceptofOTNSection1:BackgroundofOTNContentsInthenext3to5years,newbusinessdevelopmentwilldriverapidgrowthinbusinessvolume.Rapidgrowthofnewbusinessbasedbroadbandservicesoflargeparticles.Alargenumberbroadbandservicesoflargeparticlesrequireeffective

schedulingandmanagement,improvingtheQoS,tomeettheneedsofnetworkoperators.InternetAccessresidential31%BBAccInternet11%Privatelines25%VideoDistribution27%Voice(Fixed+Mobile)4%6X20052010NetworkDevelopmentunderIP-driventrendBroadbandbusinessisboomingwhichproposednewrequirementsonthetransmissionnetwork!DataServices(ATM/FR,VPN)2%Page4PDHSDH?TheRoadofTransportNetworkTechnologyEvolutionPage5AnalysisofthedifferentTransmissionTechnologyPDHSDHWDMPDH:Quasi-synchronousdigitalhierarchy，ithavebetteradaptabilityforpointtopointcommunication.

However,PDHnetworklackofmanagementcapacity.SDH：synchronousdigitalhierarchy.Ithasmanyadvantages,suchasstandardopticalinterface,apowerfulnetworkmanagementcapabilities.However,itcannotprovideuslarge-capacityandhigh-speed.WDM：Largebandwidth,lowtransmissioncosts,adaptingtohigh-speedlarge-capacitytransmission.

Butthenetworkisnotflexibleandcannotachieveeffectivemanagement.WDMSDH/ASONOurCurrentRequirementsLargebandwidthandlargeparticlesHighnetworksurvivabilityandreliability

Highnetworkefficiency，providebusinessquicklyLow-cost

networkmusteasytoexpandEasyforEquipmentmanufacturerstoconnectPage7Demanddrivestechnologydevelopment

SohowcanwehavetheadvantagesofSDHandWDMinthesametime?Then…OTNcameintobeingPage8

Chapter1Background&ConceptofOTNSection2:ConceptofOTNPage9ContentsConceptofOTN

OTNconceptproposed：In1998,ITU-Tformallyproposedtheconcept,andtookitasanidealbasisforfuturenetworkevolution.OTN：OpticalTransportNetworkOpticalTransportNetwork(OTN)iscomposedofasetofOpticalNetworkElementsconnectedbyopticalfiberlinks,abletoprovidefunctionalityoftransport,multiplexing,routing,management,supervisionandsurvivabilityofclientsignals,accordingtotherequirementsgiveninRec.G.872.AnOpticalTransportNetworkisantransportnetworkbasedonWDMtechnology.Itisthenext-generationbackbonenetwork.Page10FrameworkofOTNInFebruary1999,G.872,the

first

proposal

ofOTN

wasapproved.Nowadays,OTNstandardsystemhasbeenimproved.

ManagementinformationmodelG.874.1/875ArchitectureaspectsG.872PhysicallayercharacteristicsG.959.1/692/693EquipmentmanagementAspectsG.874/7710Jitter/driftperformanceG.8251OpticalsafetyregulationsG.664BERG.8201EquipmentfunctionG.806/G.798Structure/Mapping/OverheadG.709APSG.873.1/808.1Page11OTNCharacteristicOTNHierarchydefinedinG.872ComplexframingdefinedinG.709InterfacedefinedinG.709，Includingwavelengthdivisionsideandclientside(typicallyusedforinterconnection)Reconfigurableopticaladd-dropmultiplexerODUkcross（OTH)LoadcontrolplanePage12OTNcharacteristicNetworkHierarchyofOTNOPU→ODU→OTU ElectricallayerOCh→OMS→OTS OpticallayerROADMOTNOpticallayerandelectricallayerperformancemonitoringOpticallayerperformancemonitoringOTU（OTNframestructure）OTNincludeselectrical-layernetworkandoptical-layernetworkPage13OTNTechnicalSuperiority1.Full-serviceaccessandlargecapacitytransmission2.Maintenance&Management3.NetworkingandProtection

4.FlexiblegroomingSDH、Ethernet、IP、ATM、GFPtransparenttransmissionTbitsleveltransportcapabilityWealthofoverheadbytesSixlevelsofindependentTandemConnectionMonitoring(TCM)SupportingtraditionalWDMopticallayerprotectionIntelligentprotectionandrestorationwithMeshnetworks

Opticallayercross-connectMultiplexerandgroomingsub-wavelengthservices(ODUk/GE)

ODUkcascadeandvirtualcascadePage14OTNSuperiority

Chapter2HierarchyofOTNPage15ContentsOTNHierarchicalStructureTheopticallayercanbedividedinto

：

OpticalChannel(OCh)

、OpticalMultiplexSection

、

OpticalTransmissionSection(OMS)OChcanbedividedintothreesub-layerelectronicfield：

OpticalPayloadUnit（OPU）

、OpticalDataUnit（ODU）、

OpticalTransportUnit（OTU）OpticallayerOpticalChannellayernetwork（OCh）OpticalMultiplexSectionlayernetwork（OMS）OpticalTransmissionSectionlayernetwork（OTS）ClientlayerOChPayloadUnit（OPU）OChDataUnit（ODU）OChtransportUnit（OTU）OChOpticallayerThreeelectronicfieldlayersIP、ETHERNET、ATM、SDH/SONETPage16OTNHierarchicalStructureEssentially，OTNconsistsoffollowingparts：OpticalTransmissionSection(OTS)OpticalChannel(OCh)OpticalMultiplexSection(OMS)OpticalDataUnit(ODU)OpticalTransportUnit(OTU)OpticalPayloadUnit(OPU)

Page17FunctionofOTNeachlayerOTNOChOMSOTSRealizeestablishment,managementandmaintenanceforend-to-endopticalpathOpticallayerheaderprocessingOpticalchannelmonitoringAdaptiontoelectricallayer、multi-serviceaccessRealizethenetworkingfunctionofmulti-wavelengthopticalsignalsRealizetheprocessingofOMS’headerThemanagementandmaintenanceofOMSProvidethefunctionofopticalsignalstransportindifferenttypesofopticalmediumThemanagementandmaintenanceofOTSPage18ClientWrapperODUkFECOHOPUkOHAssociatedoverheadClientOHElectricallayerClientODUkFECOHOPUkOHClientOHOChPayloadE/OE/OOPS0OPSnOMSnOTSnOTM-nr.mOTM-0.mOTM-n.mNon-associatedoverheadOOSOSCOHOHOHOChPayloadOCCOCCOCCOpticallayer

ClientsignalsOTUkOTNhierarchicalstructureandrelationshipamonginformationflowPage19Page20

Chapter3G.709IntroductionSection1:FrameStructure&OPUOverheadContentsPage21G.709introductionPage22382540801781415161738241234OPUkPayloadOTUkFECOTUkOHOTUk－OpticalChannelTransportUnit-kAlignmFramealignment

K:rate-levelK

12.5G210G340GFrameStructureODUk－OpticalChannelDataUnit-k

ODUkOHOPUk－OpticalChannelPayloadUnit-k

OPUkOHClientSignalClientSignalmappedinOPUkPayloadPage23ComparedwithSDHStructure：4×4080，invariableRate：Variable

20.420kHz(48.971s)forOTU182.027kHz(12.191s)forOTU2329.489kHz(3.035s)forOTU3Contain：OPUk、ODUk、OTUk、FECG.709FrameStructureSDHFrameStructure

Structure：9×270n，Variable

Rate：8000F/s，invariableContain：SectionOverhead、pointerChannelOverhead、PayloadPage24PSIEachOPUkoverheadprovidesone

byteofPSI;OnecompletePSIinformationstructurecomposedwith256PSIinacomplexframe;PSI[0]is1byteofpayloadtype（PT）,PSI[1]-PSI[255]arereserved.OPUkOverhead(k=1,2,3)Page25OPUkOverhead(k=1,2,3)MSB

1

2

3

4LSB

5

6

7

8Hexcode

(Note1)Interpretation0000000101Experimentalmapping0000001002AsynchronousCBRmapping,0000001103BitsynchronousCBRmapping0000010004ATMmapping0000010105GFPmapping0000011006VirtualConcatenatedsignal0001000010Bitstreamwithoctettimingmapping0001000111Bitstreamwithoutoctettimingmapping0010011020ODUmultiplexstructure0101010155Notavailable0110011066Notavailable1000xxxx80-8FReservedcodesforproprietaryuse11111101FDNULLtestsignalmapping11111110FEPRBStestsignalmapping11111111FFNotavailablePTOverheadinstructions

：Page26JCOPUkOverhead(k=1,2,3)3bytesThefirstsixbitsof

Eachbytearereserved;ThelasttwobitsindicatePositiveandnegativeadjustmentbetween

ClientdataandOPUk.Page27

ContentsChapter3G.709IntroductionSection2:OTUk&ODUkOverheadOTUk/ODUkOverheadPage28Page29OTUk/ODUkOverhead(k=1,2,3)EXPTCMACTTCM5TCM4TCM3TCM2TCM1TCM6GCC1GCC2FTFLPMRESRESAPS/PCCSMRESGCC0FASMFASTCMiSTATTTIBIP-81234567812312345678BEI/BIAEBDI12345678181471234TTIBIP-812345678123PM12345678BEIBDISTAT12345678MFAS:Multi-FrameAlignmentSignalPCC:ProtectionCommunicationControlchannelPM:PathMonitoringPSI:PayloadStructureIdentifierRES:ReservedforfutureinternationalstandardisationSM:SectionMonitoringTCM:TandemConnectionMonitoringACT:Activation/deactivationcontrolchannelAPS:AutomaticProtectionSwitchingcoordinationchannelEXP:ExperimentalFAS:FrameAlignmentSignalFTFL:FaultType&FaultLocationreportingchannelGCC:GeneralCommunicationChannel6Page30OTUk/ODUkOverhead(k=1,2,3)MultiframeAlignmentSignal－MFAS（1Byte）,256framescomprisedamultiframe(256Bytes)FrameAlignmentSignal－FAS（6Bytes)OA1＝F6h，OA2＝28hindicatethebeginningofaframeAccessPointIdentifier（SAPI，DAPI）typecodedefinedbySuggestionT.50OTUk/ODUkOverhead(k=1,2,3)Page32OTUk

Overhead(k=1,2,3)OTUkSMoverheadBIP-8byte(1Byte)OTUkSMoverhead（3Bytes)Page33OTUk

Overhead(k=1,2,3)OTUkSMoverhead:BackwardErrorIndicationandBackwardIncomingAlignmentError(BEI/BIAE)

UsedtoreturnthenumberofErrorandIAEreceivedbyOTUk,“1011”equalstoBIAEOTUkSMBEI/BIAE

bits

1234BIAEBIPviolations0000false00001false10010false20011false30100false40101false50110false60111false71000false81001,1010false01011true01100to1111false0Page34OTUk

Overhead(k=1,2,3)OTUkSMoverhead:BackwardDefectIndication(BDI)UsedtoreturnsignaldefectstatusreceivedbyOTUk;“1”equalstoDefectstatus，else“0”OTUkSMoverhead:IncomingAlignmentError（IAE）UsedtoindicateAlignmenterrorstatusreceivedbyOTUk；“1”equalstoAlignmenterror，else“0”GCC:GeneralCommunicationChannelJustlikeDC1~DC12inSDH,usedtocommunicatebetweenOTUkterminal.Page35ODUk

Overhead(k=1,2,3)ODUkPMoverheadOTUkSMoverheadPage36ODUk

Overhead(k=1,2,3)ODUkPMOverhead:PathStatusindication(STAT)UsedtoindicatePathstatusPMbyte3,

bits

678Status000Reservedforfutureinternationalstandardization001Normalpathsignal010Reservedforfutureinternationalstandardization011Reservedforfutureinternationalstandardization100Reservedforfutureinternationalstandardization101Maintenancesignal:ODUk-LCK110Maintenancesignal:ODUk-OCI111Maintenancesignal:ODUk-AISPage37ODUk

Overhead(k=1,2,3)ODUkFaulttypeandFaultlocationreportingchannel（FTFL)0～127Byte

forwardindicationfield，128～255Byte

backwardindicationfieldForwardandBackwardindicationfieldinclude3sub-fieldsyetPage38ODUk

Overhead(k=1,2,3)FaultIndicationCodeForward/BackwardoperatoridentifierField(9bytes)IndicateForward/BackwardoperatorandCountrycode.othersusedbyoperatorseparately,nostandardization.FaultindicationcodeDefinition00000000NoFault00000001SignalFail00000010SignalDegrade00000011...11111111ReservedforfutureinternationalStandardizationGCC1GCC2:thefunctionissameasGCC0APS/PCC&EXP&TCMACK,nostandardization,reservedforfuture.ODUk

Overhead(k=1,2,3)OTNMeaningSDHOTNMeaningSDHFASFrameAlignmentA1/A2FTFLFaulttype&FaultLocationreport

MFASMultiframeAlignmentH4GCC1~2GeneralCommunicationChannelD1~D12SMSectionMonitoring

APS/PCCAutomaticProtectionSwitchK1/K2/K3TTITrialTraceIdentifierJ0PSIPayloadStructureIdentifier

BIP-8BIP-8CheckbytesB1/B2PTPayloadTypes

BEIBackwardErrorIndicationREIJCAdjustmentControlC1/C2BDIBackwardDefectIndicationRDINJONegativeAdjustmentS1/S2TCM1~6TandemConnectionMonitoringN1/N2PJOPositiveAdjustmentS1/S2STAT

PMPathMonitoring

OTNOverheadcomparewithSDHPage40

ContentsChapter3G.709IntroductionSection3:Mapping&MultiplexingMappingClientSignalsIP,ETHERNETATMMultiplexingWavelengthDivisionMultiplex(WDM)TimeDivisionMultiplex(TDM)Page41MappingIPandEthernetG.709providesanencapsulationforpacketbasedclientsignalsThereisnoneedforSDHor10G-EthernettoencapsulateIPAnewprotocolisbeingdefined:GenericFramingProcedureBandwidthforGFPstreaminODU1:2488320kbit/sODU2:9995276kbit/sODU3:40150519kbit/sPage42GenericFramingProcedureG.7041Page43MappingATMG.709providesamappingforcellbasedclientsignalsMappingATMintoODUkissimilartomappingintoSDHBandwidthforATMstreaminODU1:2488320kbit/sODU2:9995276kbit/sODU3:40150519kbit/sPage44TimeDivisionMultiplex-StructurePage45WavelengthDivisionMultiplex-StructurePage46Page47

ContentsChapter4OTNkeyTechnologiesSection1:OTHIntroductionOTHequipments:wavelengthleveltrafficcrosscompletethewavelengthcrossandscheduling

.TrafficparticlesODUk（k=1,2,3）RateoftrafficparticlesODU1（2.5Gb/s）、ODU2（10Gb/s）、ODU3（40Gb/s）

KeyTechnologiesOTH

OTH:OpticalTransmissionHierarchyPage48ODU1/ODU2/ODU3crossStrongsupportforOTNoverhead

Flexiblenetworking,ProtectionandRestorationSupportIntelligentcontrolplaneShortcomings

:-Smallparticletraffic

isnotsuitableforscheduling.

-Technologiesneedfurtherimprovement,suchasringprotectiontechnology,ProtectionandRestorationtechnology.

Page49

KeyTechnologiesOTHRealization

：OTUdividedintotheClientsideandGroupofroadside

Features:Largetrafficparticles：1-100Gb/sLargecrossparticlesThereisnouniformcrossparticleslikeVC4ProtectiontheScheduling

OnlyneedtochangeinterfaceplatewhentrafficchangesImplementationofOTHCross

Page50OTNOTNOTNOTNCrossmatrixClientClientClientClientOTHsystem:SDHequipmentremoved,increasingtheODUkcrossmatrix;

ODUkcrossmatrixachievedbycrossplate.Equipmentcomparison:OTHandSDH+WDM

Page51SDH+WDMsystemOTHsystemSDH+WDMsystemOTHsystemOpticallayerOpticallayerOTN-sideadaptationClientsignalClientsignalSDHEquipmentSDHsignaladaptationOTN-sideadaptationOTN-sideadaptationClient-sideadaptationODUkE-CrossMatrixPage52

ContentsChapter4OTNkeyTechnologiesSection2:ROADMTechnologyPage53TheEvolutionofOpticalNetworks

WDMPointtopointtransmissionMulti-pointnetworkROADM、WXCandASONrealizeopticallayerinterconnectionPage54OTNopticallayernetwork-ROADMThemainadvantage：(1)achievethe

pureopticaldomainnetwork;(2)withoutOEOconversion,reducenetworkcosts;(3)forlargeparticles

businesses,suchas10Gb/s,40Gb/s.Shortcoming：(1)transmissiondistancelimitation(CD,PMD,nonlinear,OSNR);(2)thehigherinitialinvestment.IP/MPLS/SDHIP/MPLS/SDHIP/MPLS/SDHWavelengthcross-level,purelightprocessing

introductionofintelligentcontrolplaneCD/PMD/nonlinear/OSNR？？Page55OpticallayerschedulingThedistributionofWavelengthresourcesinWDMequipment:FOADM（FixedOpticalAdd/DropMultiplexer）ROADM（ReconfigurableOpticalAdd/DropMultiplexer）FOADM:re-adjustthedistributionofwavelengthresourcesisdiffitcult.ROADM:Byblockingorcross-wavelength,Wavelengthresourcescanbeallocatedflexibly,dynamically.ROADMtechnology

remotlyanddynamicallyadjustthestateofwavelength，thenumberofwavelengthsupto40waves.Page56FOADM

&ROADMFOADM

ROADMλ1~λnλ1~λ4OAOAλ1~λnOADOADλ5~λ8λ1~λnλ1~λnOAOAλ1~λnROADMOAλ1~λnfixedwavelengthup/down,theinitialplanning

complex,upgradedifficulties.Complexupgradeproject,operationand

maintenancecostshigh;Manualconfiguration,increasehumanerror

possible.

multi-direction,Up/downwavelengthflexibility

Reconfiguredthrougharemotenetwork

managementsystem

Lowoperationandmaintenancecosts

Trafficforlargeparticles

Page57FOADMOMTfunctionalunit：OTU（LMS2E、OTU2S、OTU2E…）OMU/ODU（OMU48-O、ODU48-O…）OBA/OLA/OPA（OA、PA、RAU…）OSC/ADU（OSCAD）EMU(EMU)Page58

ROADMOpticallayerservicesautomaticschedulingby100GHzor50GHzthatcanachieveopticalcross;Trafficschedulingwithelectricallayerandprotection;Thecostofstaionishigh;Trafficforlargeparticles.Page59Withexistingtechnology,ROADMcanbeeasilyachievedfourlightdirectionscrossforeachdirectionof40or80waves,crosscapacityof1.6Tor3.2T.Itisexpectedtosupport8directionsquickly.OSCADOSCADDCMOSCADDCMOSCADDCM………………………………………………………………………………………………LocalAddLocalDropWestEastSouthNorthROADMPage60

ContentsChapter4OTNkeyTechnologiesSection3:RealizationofROADMCurrently,therearethreecommontechniquesinROADMsubsystem：PLC（PlanarLight-waveCircuits）WB（WavelengthBlocker）WSS（WavelengthSelectiveSwitch）RealizationofROADMPage61

TheworkingprincipleofWB

Wavelengthontheroadchosenwillcombinewiththeotheropticalsignalsoforiginaltransmitionsignalsthroughacouplertocontinuesendsignalsdowntransmissioncombination.Page62TechnologyofWB

2DdeviceControlthepowerofeachwavelengthBlocking/bywavelengthBalancedSpectrum

;LCD/MEMSwavelengthblockercansupportmorechannelsoflight,andsmallerintervals;50G/100GHz,128/64lightchannels

itcanreducedto25GHzint