以太網(wǎng)OAM（802.3ah）協(xié)議分析及測試關(guān)注點DOCUMENTID:PRODUCT:RELEASE:2.0FEATURE:SUBSYSTEM:DISTRIBUTETO:1 以太網(wǎng)OAM簡介 22 以太網(wǎng)OAM在網(wǎng)絡(luò)上的應(yīng)用 23 OAMPDU報文解析及工作原理 2 報文解析 2 幾種最常見的OAMPDU用法： 2 InformationOAMPDU 2 EventNotificationOAMPDU 2 LoopbackControlOAMPDU 2 以太網(wǎng)OAM工作原理： 2 建立以太網(wǎng)OAM連接： 2 鏈路監(jiān)控 2 遠(yuǎn)端故障檢測 2 遠(yuǎn)端環(huán)回 24 Featurelist 2 主要功能 2 工作原理 2 EventNotification的處理 2 OAMPDU報文 2 LocalInformationTLVs 2 RemoteInformationTLVs 2 LinkEventTLVs 2 VariablesDescriptorsandContainers 25 測試關(guān)注點： 2 概述： 2 具體測試點： 2

以太網(wǎng)OAM簡介以太網(wǎng)OAM（Operations,AdministrationandMaintenance，操作、管理和維護(hù)）是一種監(jiān)控網(wǎng)絡(luò)問題的工具。它工作在數(shù)據(jù)鏈路層，利用設(shè)備之間定時交互OAMPDU（OAMProtocolDataUnits，OAM協(xié)議數(shù)據(jù)單元）來報告網(wǎng)絡(luò)的狀態(tài)，使網(wǎng)絡(luò)管理員能夠更有效地管理網(wǎng)絡(luò)。以太網(wǎng)OAM在網(wǎng)絡(luò)上的應(yīng)用隨著數(shù)據(jù)業(yè)務(wù)的廣泛應(yīng)用，以太網(wǎng)在通信網(wǎng)絡(luò)中扮演著越來越重要的作用，但是以太網(wǎng)與傳統(tǒng)的SDH相比，在網(wǎng)絡(luò)故障告警、鏈路質(zhì)量、維護(hù)手段等方面都略遜一籌。于是國際標(biāo)準(zhǔn)化組織IEEE，先后推出了802.3ah(2004)和802.1ag(2007)兩個標(biāo)準(zhǔn)化協(xié)議來強(qiáng)化以太網(wǎng)在維護(hù)、告警方面的能力。是偏網(wǎng)絡(luò)和應(yīng)用的OAM，主要用在匯聚層和核心層上，它的OAMPDU報文能夠傳輸多跳。它不僅能夠監(jiān)測鏈路質(zhì)量、收集告警，還能夠?qū)崿F(xiàn)電信級快速倒換以及traceroute、ping等功能。在TN705/725上的MPLSOAM就部分參考了802.1ag的協(xié)議，大家有興趣可以仔細(xì)研究下。由于TN703產(chǎn)品主要定位于接入網(wǎng)絡(luò)邊緣，因而目前只要求支持802.3ah的以太網(wǎng)OAM即可。802.3ah以太網(wǎng)OAM最主要的功能主要有三個方面，分別是：1、鏈路性能監(jiān)測：可以對鏈路故障進(jìn)行檢測；2、故障偵測和告警：可以在鏈路出現(xiàn)故障時及時通知網(wǎng)絡(luò)管理員；3、環(huán)路測試：通過將非OAMPDU環(huán)回來檢測鏈路故障。注：下文中“以太網(wǎng)OAM”如未特殊標(biāo)明，均指802.3ah的以太網(wǎng)OAM。OAMPDU報文解析及工作原理報文解析幾個重要字段的含義如下：。Destaddr：以太網(wǎng)OAM報文的目的MAC地址，為組播MAC地址0180c2000002。。Sourceaddr：以太網(wǎng)OAM報文的源MAC地址，為發(fā)送端的橋MAC地址，該地址是一個單播MAC地址。。Type：以太網(wǎng)OAM報文的協(xié)議類型，為0x8809。。Subtype：以太網(wǎng)OAM報文的協(xié)議子類型，為0x03。。Flags：Flags域，包含了以太網(wǎng)OAM實體的狀態(tài)信息。。Code：本字段指明了OAMPDU的報文類型。0x00表示InformationOAMPDU、0x01表示EventNotificationOAMPDU、0x04表示LoopbackControlOAMPDU

Flags域：主要用來標(biāo)示鏈路的故障信息：值得注意的是對于CriticalEvent,DyingGasp,andLinkFault這些鏈路告警的具體定義，在802.3ah協(xié)議中是沒有注明的。這可能要廠家根據(jù)需要自行定義。幾種最常見的OAMPDU用法：在ETHOAM中最常見的三種OAMPDU報文分別是InformationOAMPDU、EventNotificationOAMPDU和LoopbackControlOAMPDU，下面將分別加以介紹：InformationOAMPDU用于將以太網(wǎng)OAM實體的狀態(tài)信息（包括本地信息、遠(yuǎn)端信息和自定義信息）發(fā)給遠(yuǎn)端的以太網(wǎng)OAM實體，保持以太網(wǎng)OAM連接。具體的報文結(jié)構(gòu)形式：EventNotificationOAMPDU（事件通知OAMPDU）一般用于鏈路監(jiān)控，是用于對連接本端和遠(yuǎn)端以太網(wǎng)OAM實體的鏈路發(fā)生的故障進(jìn)行告警。具體的報文格式：LoopbackControlOAMPDU（環(huán)路控制OAMPDU）報文主要用于遠(yuǎn)端環(huán)回控制。環(huán)回控制OAMPDU報文用來控制遠(yuǎn)端設(shè)備的OAM環(huán)回狀態(tài)，該報文中帶有使能或去使能環(huán)回功能的信息，根據(jù)該信息開啟或關(guān)閉遠(yuǎn)端環(huán)回功能。具體的報文格式：以太網(wǎng)OAM工作原理：建立以太網(wǎng)OAM連接：以太網(wǎng)OAM連接過程也稱作Discovery階段，本階段是OAM實體發(fā)現(xiàn)遠(yuǎn)端設(shè)備的OAM實體，并與之建立穩(wěn)定對話的過程。在這個階段中，相連的以太網(wǎng)OAM實體（即使能OAM功能的端口）通過交互InformationOAMPDU向?qū)Χ送▓蟾髯缘囊蕴W(wǎng)OAM配置信息及本地節(jié)點支持的以太網(wǎng)OAM能力信息。OAM實體收到對端配置參數(shù)后，決定是否同意建立OAM連接，如果兩端的以太網(wǎng)OAM對Loopback功能、單向鏈路檢測及鏈路事件的配置都通過檢查時，以太網(wǎng)OAM協(xié)議將在鏈路層開始正常工作。我們可以選擇兩種模式來進(jìn)行以太網(wǎng)OAM的連接：主動模式和被動模式兩種模式下的設(shè)備處理能力如下表所示：處理能力主動模式被動模式初始化以太網(wǎng)OAMDiscovery過程可以不可以對以太網(wǎng)OAMDiscovery初始化過程的響應(yīng)可以可以發(fā)送InformationOAMPDU可以可以發(fā)送EventNotificationOAMPDU可以可以發(fā)送不攜帶TLV的InformationOAMPDU可以可以發(fā)送LoopbackControlOAMPDU可以不可以對LoopbackControlOAMPDU的響應(yīng)可以，但需要對端也處于主動模式下可以發(fā)送組織指定的OAMPDU可以可以發(fā)送VariableRequestOAMPDUs可以不可以發(fā)送VariableResponseOAMPDUs可以可以發(fā)送帶團(tuán)隊屬性的特殊OAMPDUs可以可以當(dāng)然在兩個peertopeer的端口上，都配置成active端口也是可以的。以太網(wǎng)OAM連接建立后，兩端的OAM實體通過發(fā)送InformationOAMPDU保持連接。若在5秒鐘內(nèi)沒有收到對端OAM實體的InformationOAMPDU，則認(rèn)為連接超時，需要重新建立OAM連接。鏈路監(jiān)控鏈路監(jiān)控用于檢測和發(fā)現(xiàn)鏈路層的故障。以太網(wǎng)OAM利用EventNotificationOAMPDU的交互來進(jìn)行鏈路監(jiān)控。當(dāng)鏈路故障發(fā)生時，本地鏈路監(jiān)控到故障后，將向?qū)Χ艘蕴W(wǎng)OAM實體發(fā)送EventNotificationOAMPDU，通報一般鏈路事件。我們可以通過觀察日志信息動態(tài)地掌握網(wǎng)絡(luò)的狀況。一般鏈路事件的定義如下：一般鏈路事件定義錯誤信號事件單位時間內(nèi)的錯誤信號數(shù)量超過定義的閾值錯誤幀事件單位時間內(nèi)的錯誤幀數(shù)量超過定義的閾值錯誤幀周期事件指定幀數(shù)N為周期，在收到N個幀的周期內(nèi)錯誤幀數(shù)超過定義的閾值錯誤幀秒數(shù)事件指定M秒數(shù)下有錯誤幀的秒數(shù)超過了定義的閾值（錯誤幀秒的定義：在某一秒內(nèi)發(fā)生了錯誤幀，則該秒為錯誤幀秒）

遠(yuǎn)端故障檢測OAMPDU定義了一個標(biāo)志（Flag域）允許以太網(wǎng)OAM實體把該故障信息傳送給對端。該標(biāo)志可以表示下列緊急鏈路事件：.鏈路故障（LinkFault）：對端鏈路信號丟失。.致命故障（DyingGasp）：不可預(yù)知的狀態(tài)發(fā)生，比如電源中斷。.緊急事件（CriticalEvent）：不能確定的緊急事件發(fā)生。以太網(wǎng)OAM連接過程中是不斷的發(fā)送InformationOAMPDU的，本端OAM實體可以將本端發(fā)生的緊急鏈路事件信息通過InformationOAMPDU告訴遠(yuǎn)端OAM實體。當(dāng)A與B之間的鏈路有一條發(fā)生故障時，B設(shè)備就會立即將含有鏈路故障信息的OAMPDU報文通過另一條鏈路發(fā)送給A。這樣，可以通過觀察日志信息動態(tài)地了解鏈路的狀態(tài)，對相應(yīng)的錯誤及時進(jìn)行處理。需要注意的是遠(yuǎn)端的故障監(jiān)測只能工作在雙發(fā)雙收的鏈路上，即雙向鏈路中有一條失效，另一條還繼續(xù)工作的那種情況。

遠(yuǎn)端環(huán)回LoopbackOAMPDU的底層轉(zhuǎn)發(fā)流程：遠(yuǎn)端環(huán)回只有在以太網(wǎng)OAM連接建立完成后才能實現(xiàn)。在連接建立的情況下，主動模式的OAM實體發(fā)起遠(yuǎn)端環(huán)回命令，對端實體對該命令進(jìn)行響應(yīng)。當(dāng)遠(yuǎn)端處于環(huán)回模式下，除了OAMPDU報文以外的所有報文都將按照原路返回，而OAMPDU報文將繼續(xù)上送至被環(huán)回設(shè)備的CPU進(jìn)行處理。通過進(jìn)行環(huán)回檢測可以及時發(fā)現(xiàn)網(wǎng)絡(luò)故障，并通過分段環(huán)回檢測來幫助定位故障發(fā)生的具體區(qū)域。Featurelist主要功能tmeaueSublaselu/CmmntSppotOOAMobetcas036MustCSIOAMcinterieitracs725MustSnenalsevcenefae72MustACAtvemo72MustASasiemod72MustLOAMremteopba721ble7–8MustUNIUiieconloprton7212,ble7–8ReqiesupprtforundrcioalpeainasdeiednCluse6.MustEVNTinkEens743.,75MustARaraleRtival743.,743.MayOOgaiatonSeciOAMPDU743.MayOEOgaiatonSecicEens753.5MayOIOgaiatonSecicnomtonT752.May工作原理ItemFeatureSubclausealue/CommentSupportOFS1Passivemodelimitedtransmission57CannotsendariableRequestorLoopbackControlOAMPDUsMustOFS2Discoverystatediagram57ImplementedasdefinedinFigure57–5MustOFS3ransmitstatediagram57ImplementedasdefinedinFigure57–6MustOFS4OAMPDUtransmissionwhenlocal_pduissettoLF_INFO57OnlyInformationOAMPDUswithLinkFaultbitofFlagsfieldandwithoutInformationTVscanbetransmittedMustOFS5OAMPDUtransmissionwhenlocal_pduissettoRX_INFO57NoOAMPDUtransmissionallowedMustOFS6OAMPDUtransmissionwhenlocal_pduissettoINFO57OnlyInformationOAMPDUscanbetransmittedMustOFS7OFS8OAMPDUtransmissionwhenlocal_pduissettoAN:OAequestserviceprimitivewithoneormorecriticallinkeventparametersOAquestserviceprimitive5757RequeststransmissionofInformationOAMPDUwithappropriatebitsofFlagsfieldsetRequeststransmissionofOAMPDUMustOFS9OFS10OAMPDUFlagsfieldreservedencodingsRemotetableandRemoteEvaluatingbitsLocaltableandLocalEval-uatingbitsable57–3able57–3Encodingof0x3isnottransmittedEncodingof0x3isnottransmittedMustOFS1Reservedbitsable57–3ReservedbitsarezeroontransmissionMustOFS12OAMPDUCodefield57OnlydefinedCodefieldvaluesarepermittedintransmittedOAMP-DUsMustOFS13OAMPDUreceptionwhenlocal_pduisnotsettoANY57OnlyInformationOAMPDUsaresenttoOAMcliententityMustOFS14OAMPDUreceptionwhenlocal_pduissettoANY57AllOAMPDUsaresenttoOAMcliententityMustOFS15Multiplexerstatediagram57ImplementedasdefinedinFigure57–7MustOFS16Multiplexertransparentpass-through57Providetransparentpass-throughofframesfromsuperiorsublayertosubordinatesublayerMustOFS17EffectofOAMPDUonaframealreadysubmittedtosubordinatesublayer57HasnoeffectMustOFS18Parserstatediagram57ImplementedasdefinedinFigure57–8MustEventNotification的處理ItemFeatureSubclauseValue/CommentSupportEV1ResponsetoCriticalEventsSet/clearFlagbitsbasedonOAM_CTL.requestserviceprimitiveMustEV2CriticalEventreceptionIndicatedviaFlagsfieldofOAMPDU.indicationserviceprimitiveMustEV3LinkEventreceptionIndicatedviaOAMPDU.indicationserviceprimitivewithallreceivedEventNotificationOAMPDUsMust

OAMPDU報文ItemFeatureSubclausealue/CommentSupportPDU1TaggingOAMPDUscannotbetaggedMustPDU2OAMPDUstructureAsdefinedinFigure57–9andfielddefinitionsMustPDU3MinimumOAMPDUsizeSupportOAMPDUsminFrame-SizeinlengthMustPDU4InformationOAMPDUframestructureShowninFigure57–10MustPDU5InformationOAMPDUwhenlocal_pdusettoLF_INFODatafieldcontainszeroInformationTLVsMustPDU6PDU7InformationOAMPDUwhenlocal_pdunotsettoLF_INFOremote_state_valid=FALSEremote_state_valid=TRUEDatafieldcontainsLocalInformationTLVDatafieldcontainsLocalandRemoteInformationTLVsMustPDU8Typevalues0x03-0xFDTable57–6NottobesentMustPDU9Typevalue0xFFTable57–6NottobesentMustPDU10EventNotificationOAMPDUframestructureShowninFigure57–11MustPDU11EventNotificationOAMPDUSequenceNumberThefirsttwobytesoftheDatafieldcontainaSequenceNumberencodedasanunsigned16-bitintegerMustPDU12EventNotificationOAMPDUEvent(s)DatafieldcontainingoneormoreLinkEventTLVsfollowingtheSequenceNumberMustPDU13VariableRequestOAMPDUframestructureShowninFigure57–12MayPDU14VariableRequestOAMPDUDatafieldDatafieldcontainsoneormoreVariableDescriptorsMayPDU15VariableResponseOAMPDUframestructureShowninFigure57–13MayPDU16VariableResponseOAMPDUDatafieldDatafieldcontainsoneormoreVariableContainersMayPDU17LoopbackControlOAMPDUframestructureShowninFigure57–14MustPDU18LoopbackControlOAMPDUDatafieldDatafieldcontainsasingleOAMRemoteLoopbackcommandfromTable57–5.MustPDU19Commandvalue0x00Table57–5NottobesentMustPDU20Commandvalues0x03-0xFFTable57–5NottobesentMustPDU21OrganizationSpecificOAMPDUframestructureShowninFigure57–15MayPDU22OrganizationSpecificOAMPDUOrganizationallyUniqueIdentifierfieldContains24-bitOrganizationallyUniqueIdentifierMayLocalInformationTLVstemFetueSubluselu/CmmntSupprtLTLcalInomaionT5...Cotistefoowigfedsnormtonyp,normtonLngh,OAMeson,Rviin,ae,OAMCofguaon,OAMPDUCofguaon,OU,ndorSecicnfrmaonMustLT2LcalInomaionTVOAMrine5...1Cotis0x01ocamompinceotipeiiainMustLT3LcalInomaionTVRev-inil5...1atstzroadinrmenedachimeaLcalInomaionTVedhage.MustLT4LcalIn5...1Asefndinabe5–7MustLT5LcalInomaionTVSaeild5...1snottanmitdMustLT6Rsevdbisale5–7RsevdisaezroonrnsmsiMustLT7LcalInomaionTVOAMCnfguaonfed5...1Asefndinabe5–8MustLT8Rsevdbisale5–8RsevdisaezroonrnsmsiMustLT9LcalInomaionTVOAMPDUConiurtonild5...1Asefndinabe5–9MustLT10LcalInomaionTVOUIil5...1Asefndinabe5–10MustLT1Rsevdbisale5–9RsevdisaezroonrnsmsiMustLT12LcalnfrmaonVndrSecicInfrmtoned5...1Asefndinabe5–1Must

RemoteInformationTLVstemFetueSubluselu/CmmntSupprtRT1RmtenormtonTV5...2CotisteIfomainpeildpeiyngteRemoenormtonTVyevauendalrmanngfedsreopedromtelsteevedLcalInomaionTVfomemoeOAMper LinkEventTLVsIemFetueSubluselu/CmmntSppotET1EroedymbolPeidEvntTVsucue57531Conansheolowngild:Evntyp,EvntLngh,Evntmetmp,ErreSymblndo,ErredSymblThehod,ErrdSymbl,ErorRunnngoa,EvntRunigtlMustET2EroedFameEvntTVsrctre57532Conansheolowngild:Evntyp,EvntLngh,Evntmetmp,ErreFrmeido,EroedFameThesod,Errdrms,ErorRnnngoa,EvntRuningoalMustET3EroedFamePeodEvntTVsucue57533Conansheolowngild:Evntyp,Evntngh,Evntmetmp,ErreFrmeido,EroedameThesod,ErrdFrm,ErorRnnngoa,EvntRuningoalMustET4EroedFameSeonsSummayEvetTVsrctre57534Conansheolowngild:Evntyp,EvntLngh,Evntmetmp,ErreFrmeSeondsSummayido,EroedFameSeondsSummayThrsol,EroedFameSconsSumma,ErrRnnngoa,EvntRunigtlMustET5OgniainSpeiicventTVsucue57535Conansheolowngild:Evntyp,EvntLngh,OgniainalyUiqeIenii,OgniainSecfcauMustET6OgniainpeiicventOgniainalyUiqeIeniirie57535Conans2-itOgniainalyUiqeIeniirMustET7pevles0050xFDbe57–2NotobesntMustET8pevle0xFFbe57–2NotobesntMustVariablesDescriptorsandContainers（主要用于mib管理）tmFaueSubluseaueCommentSppotAR1araleDscptrsrcure5761Asdeiedinale7–13MayARARaraleDscptr/rabeBacheeenestrbueoesoteeeneacins57615761Ifnbectorpckgesreeene,onyatbuescanbeondwihnaibleConanerAtosaenotoudinaialeCnaiesMayAR4araleCntiertucueornatiut5762Asdeiedinale7–14MayARARaraleCntier/aralBacheeenestrbueoesoteeeneacins57625762Ifnbectorpckgesreeene,onyatbuescanbeondwihnaibleConanerAtosaenotoudinaialeCnaiesMayAR7yevauex00abe5716NtoesntMayAR8yevaus0x0-x1Fabe5716NtoesntMayAR9yevaus0x2-x2Fabe5716NtoesntMayAR0yevaus0x4-x5Fabe5716NtoesntMayAR1yevaus0x6-x7Fabe5716NtoesntMay測試關(guān)注點：概述：由于ETHOAM是TN703產(chǎn)品新增的協(xié)議模塊，有關(guān)協(xié)議一致性的測試將通過IXIA的協(xié)議測試套來進(jìn)行，以保證和標(biāo)準(zhǔn)協(xié)議的一致性。測試這邊將從以下幾個部分進(jìn)行測試：協(xié)議一致性測試：OAMPDU報文一致性測試協(xié)議狀態(tài)機(jī)測試功能測試：故障監(jiān)測鏈路監(jiān)測遠(yuǎn)端環(huán)回功能組合測試：與mac層的組合測試與lacp的組合測試與流控的組合測試性能規(guī)格測試：多端口同時啟用大流量情況測試組網(wǎng)應(yīng)用測試復(fù)雜流量測試長時間老化測試異常及攻擊測試異常操作異常攻擊具體測試點：NmberAssrtionReferenceSetup/rificationss11AMPDUsraerseasilelik,bigssdbetweenpeerOAMentities,andassuch,arentforwardedbyMACcliens(e.g.,bridgesorswitches).IEEE004Section57.1.1,12AmechanismisprovidedtoindicatetoapeerthatthereceiveathofthelocalDTEisnon-opera-iaIEEE004Section57.1.2,SummaryofObjectivesandarne13AMremoteloopbackisanintrusiveoperationthatprevensalinkfromssingfraesbetweentheMACclientofthelocalDTEandtheMACclientoftheremoteDTE.IEEESection,FrameLossDuringOAMRemoteLoopback.14heOAMclientdoesnotrespondtoilleglrequesssuchasariableRequestandLoopbackControlOAMPDUsfromPassiveDTEs.(Note:DUTasactiveshouldnotrespondtoriableRequestOAMPDUsfromssiveANVL).IEEE004Section57.2.4,Page188,ResponsiilitiesofOAMClien.IEEEStd802.3ah-2004Section57.2.4,Page188,ResponsibilitiesofOAMClient.IEEEStd802.3ah-2004Section,Page195,ActiveMode.IEEEStd802.3ah-2004Section,Page195,PassiveMode.IEEEStd802.3ah-2004Section,Page195,PassiveMode.IEEEStd802.3ah-2004Section,Page195,PassiveMode.Fntoalpcfitins21tisticsfromboththelocalandremoteDTEcanbequeriedandcomaredataytimewhiletheremoteDTEisinOAMremoteloopbackode.IEEESection57.2.1,Page196,OAMRemoteLoopback.22hsequeriscankeplacebefore,duringoraterloopbackfraeshavebeensenttotheremoteDTE.IEEESection57.2.1,Page196,OAMRemoteLoopback.23AterreceivingtheLoopbackControlOAMPDU,theremoteAMclientfirstsesislocal_ar_actionrametertoLBandislocal_mux_actionrametertoDISCARDviatheOAuestserviceprimitive,andthensendsanInformaionOAMPDUwithupdatedsateinformationrefletingislocal_a_actionsettoLBandislocal_mux_ationrametersettoDSCARD.IEEESection,Page196,InitiatingOAMRemoteLoop-back.24fanOAMclienthassentaLoopbackConrolOAMPDUandiswaitingforthepeerDTEtorespondwithanInformationOAMPDUthatindi-catesitisinAMremoteloopbackmod,andthatOAMclientreceivesanOAMremoteloopbackcom-mandfromthepeerdevice,thefollowingproce-duresarerecommended:a)IfthelcalDTEhsahighersource_addresthanthepee,itshouldenterOAMremoteloopbackmodeatthecommandofispee.IEEESection,Page196,InitiatingOAMRemoteLoop-back.IEEEStd802.3ah-2004Section,Page196,InitiatingOAMRemoteLoop-back.IEEEStd802.3ah-2004Section,Page196,DuringOAMRemoteLoopback.IEEEStd802.3ah-2004Section,Page196,ExitingOAMRemoteLoopback.IEEEStd802.3ah-2004Section,Page198,TimingConsiderationsforOAMRemoteLoopback.IEEEStd802.3ah-2004Section,Page198,TimingConsiderationsforOAMRemoteLoopback.IEEEStd802.3ah-2004Section,Page198,TimingConsiderationsforOAMRemoteLoopback.IEEEStd802.3ah-2004Section57.2.12,Page198,UnidirectionalOAMOperation.DiledFunctiosandateDiagrams31nethelcalDTEhasreceivedanInformationOAMPDUwiththeLocalInformationTVfromtheremoteDTE,thelcalDTEeinssnigIfrm-tionOAMPDUsthatconainboththeLocalandtenoainIEEESection,Page203,OAMDisco32fheAMlclDTEisinfultsaeaditiscni-uredasactiveentit,itwillsendiformationOAMP-DUsthatonlyconainLocalInformationT.IEEESection,Page203,OAMDisco33fheAMlclDTEisinfultsaeaditiscni-uredasssiveentit,itwillwaitforiformationOAMPDUsthatolyconainLocalInformationT.Withotwhichitcannotcompletediscoveryprocess.IEEESection,Page203,OAMDisco34hileintheAIT_FOR_Xsae,ifthepdu_timerexpiresandoneormoreOAMPDUshavebeensentwithinthelastseond,theransmitprocesstransitionstotheRESETsate.(Note:Checkingtrasitiontriggeredbypdu_timer_done*pdu_cnt!=10).IEEESection,Page205,ransmitateDiagram.35f,howeve,inheAI_OR_TXsate,thepdu_timerexpiresandnoOAMPDUshavebeensentwithinthelastseondandthereisnovalidrequesttosendanOAMPDUpresent,theasmitprocesstransiionstotheTX_OAMPDUsaesend-inganInformationOAMPDU.ThisprevensheDis-coveryprocessfromresarting.IEEEd802.3ah-2004Section,Page205,ransmitateDiagram.36fintheAIT_FOR_TXsate,local_pduissettoLF_INFO,theransmitprocessesurestheInfor-mationOAMPDUhastheLinkFaultbitoftheFlagsfieldsetandhasnoInformationTVsintheDaaiIEEESection,Page205,ransmitateDiagramIEEEahection.6,Page206asmitRules.37fintheAIT_FOR_TXsate,howee,theOAMsublayeretityisconfiguedtonotsendanyOAMPDUs,asindicatedbythelocal_pduvariablesettoRX_INO,theransmitfunctionwillsimplyresartthepdu_timerbyreturningtotheRESETsae.(Note:Checkingtransitiontriggeredbypdu_timer_done*lcal_pdu=RX_INF).IEEESection,Page205,ransmitateDiagram.41Reservedbis(157)shallbesettozerowhensend-inganOAMPDU,andshouldbeignoredonrecep-tionforcomaiilitywithfutureuseofreservedsoe:ecigtDUTshouldnotsendFlagswiththereservedbisseswithDUTactingasPassiveOAMDTE).IEEESection,Page210,FlagsField.Reservedbits(15:7)shallbesettozerowhensend-inganOAMPDU,andshouldbeignoredonrecep-tionforcompatibilitywithfutureuseofreservedbits.(Note:CheckingthatDUTshouldnotsendFlagswiththereservedbitsset,withDUTactingasActiveOAMDTE).IEEEStd802.3ah-2004Section,Page210,FlagsField.LocalStableandLocalEvaluatingformatwo-bit(4:3)encodingshownbelow:0x1=LocalDTEDis-coveryprocesshasnotcompleted.0x2=LocalDTEDiscoveryprocesshascompleted.0x3=Reserved.Thisvalueshallnotbesent.Ifthevalue0x3isreceived,itshouldbeignoredandnotchangethelastreceivedvalue.IEEEStd802.3ah-2004Section,Page211,FlagsField.CriticalEventbitsofFlagfieldsencodingshownbelow:1=Acriticaleventhasoccurred.0=Acriticaleventhasnotoccurred.IEEEStd802.3ah-2004Section,Page211,FlagsField.DyingGaspbitofflagfieldencodingshownbelow:1=Anunrecoverablelocalfailureconditionhasoccurred.0=Anunrecoverablelocalfailurecondi-tionhasnotoccurred.IEEEStd802.3ah-2004Section,Page211,FlagsField.LinkFaultbitofflagfieldencodingshownbelow:1=Localdevice'sreceivepathhasnotdetectedafault.IEEEStd802.3ah-2004Section,Page211,FlagsField.TheoptionalEventNotificationOAMPDU,identifiedwiththeCodefieldsetto0x01,isusedtoalerttheremoteDTEoflinkevents.IEEEStd802.3ah-2004Section,Page212,EventNotificationOAMPDU.AparticularEventNotificationOAMPDUmaybesentmultipletimeswiththesamesequencenum-ber.ANDAnyduplicateEventNotificationOAMP-DUsfollowitsoriginalwithoutadifferent,interveningEventNotificationOAMPDU.IEEEStd802.3ah-2004Section,Page213,EventNotificationOAMPDU.TheOAMclientincrementstheSequenceNumberforeachuniqueEventNotificationOAMPDUformedbytheOAMclient.IEEEStd802.3ah-2004Section,Page212,EventNotificationOAMPDU.TheoptionalVariableResponseOAMPDU,identi-fiedwiththeCodefieldof0x03,isusedtoreturnoneormoreMIBvariables.IEEEStd802.3ah-2004Section,Page214,VariableResponseOAMPDU.AVariableResponseOAMPDUneedstobesentbytheOAMclientwithinonesecondofreceiptofaVariableRequestOAMPDU.IEEEStd802.3ah-2004Section,Page214,VariableResponseOAMPDU.IfaDTEisunabletoretrieveoneormorevariables,itneedstorespondwithinonesecondandindicatetheappropriateerror(s).(Note:ANVLisrequestingaOAMRemoteStatebeforediscovery).IEEEStd802.3ah-2004Section,Page214,VariableResponseOAMPDU.IfaDTEisunabletoretrieveoneormoreattributeswithinapackageorobject,itneedstoeither:a)returntheappropriateVariableIndicationforthepar-ticular attribute(s)andreturnallotherrequestedvariablesorb)returnaVariableIndicationfortheentirepackageorobject.ANDAttributeswithinpackagesandobjectsarereturnedintheorderthoseattributesarelisted.IEEEStd802.3ah-2004Section,Page214,VariableResponseOAMPDUIEEEStd802.3ah-2004Section,Page226,FormatofVariableContainersWhenReturningPackagesandObjects.TheoptionalLoopbackControlOAMPDU,identifiedwiththeCodefieldsetto0x04,isusedtocontroltheremoteDTE'sOAMremoteloopbackstate.IEEEStd802.3ah-2004Section,Page214,LoopbackControlOAMPDU.Value0x00forLoopbackControlOAMPDUcom-mandisreserved-shallnotbetransmitted,shouldbeignoredonreceptionbyOAMclient.(Note:TestforDUTshouldnottransmitLoopbackControlOAMPDUCommandwithValue0x00).IEEEStd802.3ah-2004Section,Page215,LoopbackControlOAMPDU.Value0x03-0xFFforLoopbackControlOAMPDUcommandisreserved-shallnotbetransmitted,shouldbeignoredonreceptionbyOAMclient.(Note:TestforDUTshouldnottransmitLoopbackControlOAMPDUCommandwithvaluesgreaterthan0x02).IEEEStd802.3ah-2004Section,Page215,LoopbackControlOAMPDU.Value0x00forLoopbackControlOAMPDUcom-mandisreserved-shallnotbetransmitted,shouldbeignoredonreceptionbyOAMclient.(Note:TestforDUTshouldignoreLoopbackControlOAMPDUCommandwithValue0x00).IEEEStd802.3ah-2004Section,Page215,LoopbackControlOAMPDU.Value0x03-0xFFforLoopbackControlOAMPDUcommandisreserved-shallnotbetransmitted,shouldbeignoredonreceptionbyOAMclient.(Note:TestforDUTshouldignoreLoopbackControlOAMPDUCommandwithValue0x04).IEEEStd802.3ah-2004Section,Page215,LoopbackControlOAMPDU.AMT51nLinkEventTVs,values0x05-0xFDforypefieldisreserved-shallnotbetrasmitted,shouldbeignoredonreceptionbyOAMclien.(Note:DUTshouldntsendLinkEventTVwithtypefield0x05-0xFD).IEEE004Section57.5.3,Page219,LinkEvetTVs.52DetectionofaTVtype0x00sholdindicatetherearenomoreTVstoprocess(thelengthandvalueoftheype0x00TVcanbeignored).IEEE004Section57.5.1,Page215,Parsing.53Vswithlenths0x00or0x01sholdbeconsid-eredinvalid,andtheOAMPDUsholdbeconsi-eredtohavenomoreTVs.IEEE004Section57.5.1,Page215,Parsing.54Vswithunknownorunexpectedtypesshouldbeignred.IEEE004Section57.5.1,Page215,Parsing.IEEEStd802.3ah-2004Section57.5.1,Page215,Parsing.IEEEStd802.3ah-2004Section57.5.1,Page215,Parsing.IEEEStd802.3ah-2004Table57-7Section,Page217,LocalInformationTLV.NEGATIVEIEEEStd802.3ah-2004Sec-tion,Page216,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page216,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page216,LocalInformationTLV.IEEEStd802.3ah-2004Section57.5.2,Page216,InformationTLVs.IEEEStd802.3ah-2004Section57.5.2,Page216,InformationTLVs.IEEEStd802.3ah-2004Table57-8Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Table57-8Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page216,LocalInformationTLV.IEEEStd802.3ah-2004Section57.5.2,Page216,InformationTLVs.IEEEStd802.3ah-2004Section57.5.2,Page216,InformationTLVs.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page217,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page218,LocalInformationTLV.IEEEStd802.3ah-2004Section,Page218,LocalInformationTLV.OAMTso61nLocalInformationTVs,reservedbis(15:)shallbesettozerowhensendinganOAMPDU,andshouldbeignredonrecepionforcomatibilitywithfutureuseofreservedbis.(Note:stforDUTshouldignrereservedOAMPDUConfigurationBis).IEEESection,Page218,LcalInformaionT.62nclfrmtionVs,MaximumOAMPDUsizeis-bitfieldwhichrepresensthelrgestOAMPDU,inoctes,supportedbytheDTE.Thisvleiscmardoteremote'sMaximumPDUSizeandthesmallrofthetwoisused.IEEESection,Page218,LcalInformaionT.63heRemoteInformationTVshallbeacopyofthelastreceivedLocalInformationTVfomthereoeOAMpee,withtheexcepionoftheInformationypefield.(Noe:ithDUTasActiveAMDE).IEEESection,Page219,RemoteInformationT.64heRemoteInformationTVshallbeacopyofthelastreceivedLocalInformationTVfomthereoeOAMpee,withtheexcepionoftheInformationypefield.(Noe:WithDUTasPassiveOAMDTE).IEEESection,Page219,RemoteInformationT.65nLinkEventTVs,value0xFFforypefieldisreserved-shallntbetransmitte,sholdbeignredonreceptionbyOAMclien.(Note:DUTshouldnotsendanyLinkEvetTVwithtypefield0xFF).IEEE004Section57.5.3,Page219,LinkEvetTVs.66hiseventisgeneraedifthesymblerrorcountisequaltoorgreaterthanthespeiiedthresholdforhtpdIEEESection,Page220,ErroredSymbolPeriodEvet67ErroredSymbolPeriodEventusesalengthvalueof40(0x28).IEEESection.section(b),Page220,EventLength.68hiseventisgeneratediftheeroredframecountisequaltoorgreaterthanthespecifiedthresholdforthatpriod.IEEESection,Page221,ErroredFrameEventT.69ErroredFraeEventusesalenthvalueof26(0x1A).IEEESection,Page221,ErroredFrameEventT.610Thiseventisgeneratediftheeroredframecountisgreaterthanorequaltothespeiiedthresholdforthatpriod(forexample,iftheeroredfraecoutisgreaterthanorequalto10forthelast1,000,000raesrceiv).IEEESection,Page221,ErroredFramePeriodEvent61ErroredFraePeriodEventusesalengthvalueof28(0x1C).IEEESection,Page222,ErroredFramePeriodEvent612Thiseventisgeneraedifthenumberoferroredfraesecondsisequaltoorgreaterthanthespeci-fiedthresholdforthatperiod.IEEESection,Page222,ErroredFrameSecondsSum-ayntErroredFrameSecondsSummaryEventusesalengthvalueof18(0x12).IEEEStd802.3ah-2004Section,Page223,ErroredFrameSecondsSum-maryEventTLV.ribe71MIBvariablesarequeriedthroughtheuseofri-ableRequestOAMPDUsandreturnedthroughtheuseofariableRsponseOAMPDUs.IEEEdSection57.6,Page224,riables.72AnOAMclientmayrequestoneormorevariablesineachrialeRequestOAMPDU.IEEEdSection57.6,Page224,riables.73AnOAMclientmayrequestoneormorevariablesineachrialeRequestOAMDU.EachreturnedriableConainerresideswithinasingleariableResposeOAMPDU.IEEEdSection57.6,Page224,riables.74alue0x25-3FforcodingfieldisreservedforAttribueIndications-shallnotbetrasmitted,shouldbeignredonreceptionbyOAMclien.(Note:DUTsholdnotsendvariableindicationwithcode53IEEE004Section57.6.5,Page227,riableIndications.75DetectionofaariableBrachfieldequalto0x00shouldindicatethereaenomoreariableDscrip-torstoprocess(subsequentfieldscanbeignore).IEEE004Section57.6.3,Page226,Parsing.76DetectionofaariableBrachfieldequalto0x00shouldindicatetherearenomoreariableConain-erstoproess(subsequentfieldscanbeignred).IEEE004Section57.6.3,Page226,Parsing.77nrialeIndicatios,value0x00forcodingfieldisreserved-shallnotbetransmitte,shouldbeignoredonreceptionbyOAMclien.(Note:DUTshouldnotse