LTE典型信令流程分析介紹

1、 # ILTE典型信令流程分析介紹1.1隨機(jī)接入流程隨機(jī)接入分為基于沖突的隨機(jī)接入和基于非沖突的隨機(jī)接入兩個(gè)流程。其區(qū)別為針對(duì)兩種流程其選擇隨機(jī)接入前綴的方式。前者為UE從基于沖突的隨機(jī)接入前綴中依照一定算法隨機(jī)選擇一個(gè)隨機(jī)前綴;后者是基站側(cè)通過(guò)下行專用信令給UE指派非沖突的隨機(jī)接入前綴。具體流程如下：基于沖突的隨機(jī)接入：UEeNBRandomAccessPreambleRandomAccessResponseScheduledTransmissionJ4ContentionResolutionUE在RACH上發(fā)送隨機(jī)接入前綴；ENb的MAC層產(chǎn)生隨機(jī)接入響應(yīng)，并在DL-SCH上發(fā)送；UE的R

2、RC層產(chǎn)生RRCConnectionRequest并在映射到UL-SCH上的CCCH邏輯信道上發(fā)送；RRCContentionResolution由ENb的RRC層產(chǎn)生，并在映射到DL-SCH的CCCHorDCCH(FFS)邏輯信道上發(fā)送。基于非沖突的隨機(jī)接入 25.UUCONriXTRL-L12ASBC?OMPLlilBRAPreambleassignmentRandomAccessPreambleRandomAccessResponseENb通過(guò)下行專用信令給UE指派非沖突的隨機(jī)接入前綴(non-contcntionRandomAccessPreamble),這個(gè)前綴不在BCH上廣播的集合

3、中。UE在RACH上發(fā)送指派的隨機(jī)接入前綴。ENb的MAC層產(chǎn)生隨機(jī)接入響應(yīng)，并在DL-SCH上發(fā)送。1-2開(kāi)機(jī)附著流程1.2.1正常流程UE剛開(kāi)機(jī)時(shí)，先進(jìn)行物理下行同步，搜索測(cè)量進(jìn)行小區(qū)選擇，選擇到一個(gè)suitable或者acceptable小區(qū)后，駐留并進(jìn)行附著過(guò)程。附著流程圖如下： #25.UUCONriXTRL-L12ASBC?OMPLlilBIJHeNR #25.UUCONriXTRL-L12ASBC?OMPLlilBI.RAPreamble2.RA.Response3.RRCConneclionRequeslpleteyrequesl/ft4.RRCConnectionSetup5

4、.RRCC?onnectionSetup(?onAttachRequestPONconnectivit #25.UUCONriXTRL-L12ASBC?OMPLlilB #25.UUCONriXTRL-L12ASBC?OMPLlilBCAttachRc7.Iclenliiy/Auiheniication/Security6.InitialUHmessagequestPONconnectivityreque #25.UUCONriXTRL-L12ASBC?OMPLlilBInitialcontextsetuprequestActiVLite(litt5*AttachAcceptdefaultEP

5、Sbearercontextrequ1OUtiCopdbiliiytinquWy11.UECapabi1ityIniormatinnUECapabilityInioIndicatiI3.SecurilyIVIodeCommiind15RRC?C?oiiiieclinReconfiguralio(fVAttachAcceptAcliatedefaultISPSbearercontextreqLesl) #25.UUCONriXTRL-L12ASBC?OMPLlilB #25.UUCONriXTRL-L12ASBC?OMPLlilB16.KRCConnectionReconfiftLiration

6、Conplete17Initialcontextsetupresponse18.ULIniormationTransfcr19ActivatccUPLINKNASTRANSPORTC包含AttachCompleteet2inltHPSbeiircrcontextacceptFirstUplinkDataFirstI)own1inkData 25.UUCONriXTRL-L12ASBC?OMPLlilB #25.UUCONriXTRL-L12ASBC?OMPLlilB檢刪MUscrInactivityLiCON1LXPRBLLiASLiRHQU1SS(Cause)23.ULiC：ONILiXrR

7、HLLiASHCOMM/NO24.RRCConncclionRelease說(shuō)明:1）步驟15會(huì)建立RRC連接，步驟6、9會(huì)建立S1連接，完成這些過(guò)程即標(biāo)志著NASsignallingconnection建立完成,見(jiàn)24.301。2）消息7的說(shuō)明：UE剛開(kāi)機(jī)第一次attach,使用的IMSI,無(wú)Identity后續(xù)，如果有有效的GUTI,使用GUTIattach,核心網(wǎng)才會(huì)發(fā)起Identity過(guò)程（為上下行直傳消息）。3）消息10-12的說(shuō)明:如果消息9帶了UERadioCapabilityIE,則eNB不會(huì)發(fā)送UECapabilityEnquiry消息給UE,即沒(méi)有1012過(guò)程；否則會(huì)發(fā)送，U

8、E上報(bào)無(wú)線能力信息后,eNB再發(fā)UECapabilityInfoIndication,給核心網(wǎng)上報(bào)UE的無(wú)線能力信息。為了減少空口開(kāi)銷，在IDLE下MME會(huì)保存UERadioCapability信息，在INITIALCONTEXTSETUPREQUEST消息會(huì)帶給eNB,除非UE在執(zhí)行attach或者”firstTAUfollowingGERAN/UTRANAttachorUEradiocapability叩date”TAU過(guò)程（也就是這些過(guò)程MME不會(huì)帶UERadioCapability信息給eNB,并會(huì)把本地保存的UERadioCapability信息刪除,eNB會(huì)問(wèn)UE要能力信息,并報(bào)給

9、MME。注：MUEradiocapabilityupdate*1TAUisonlysupportedforchangesofGERANandLJTRANradiocapabilitiesinECM-IDLE.）。在CONNECTED下,eNB會(huì)一直保存UERadioCapability信息。UE的E_UTRAN無(wú)線能力信息如果發(fā)生改變，需要先detach,再attache4）發(fā)起UE上下文釋放（即2125）的條件：eNodeB-initiatedwithcausec.g.O&MIntervention,UnspecifiedFailure,UserInactivity,RepeatedRRCs

10、ignallingIntegrityCheekFailure,ReleaseduetoUEgeneratedsignallingconnectionrelease,etc.;orMME-initiatedwithcausee.g.authenticationfailure,detach,ec.5）eNB收到msg3以后，DCM給USM配置SRB1，配置完后發(fā)送msg4給UE；eNB在發(fā)送RRCConnectionReconfiguration前，DCM先給USM配置DRB/SRB2等信息，配置完后發(fā)送RRCConnectionReconfiguration給UE,收到RRCConncction

11、RcconfigurationComplctc后,控制面再通知用戶面資源可用。 # #6）消息13-15的說(shuō)明：eNB發(fā)送完消息13,并不需要等收到消息14,就直接發(fā)送消息15o7）如果發(fā)起IMSIattach時(shí),UE的IMSI與另外一個(gè)UE的IMSI重復(fù),并且其他UE己經(jīng)attach,則核心網(wǎng)會(huì)釋放先前的UE。如果IMSI中的MNC與核心網(wǎng)配逬的不一致，則核心網(wǎng)會(huì)回復(fù)attachrejecto8）消息9的說(shuō)明：該消息為MME向eNB發(fā)起的初始上下文建立請(qǐng)求，請(qǐng)求eNB建立承載資源，同時(shí)帶安全上下文，可能帶用戶無(wú)線能力、切換限制列表等參數(shù)。UE的安全能力參數(shù)是通過(guò)amchrequest消息帶給

12、核心網(wǎng)的，核心網(wǎng)再通過(guò)該消息送給eNB。UE的網(wǎng)絡(luò)能力（安全能力）信息改變的話，需要發(fā)起TAUo #1.2.2異常流程1.2.2.1RRC連接建立失敗 # # # T300 #1.2.2.2核心網(wǎng)拒絕eNBEPCUE1.RAPreamble2.RAResponse3.RRCConnectionRequest4.RRCConnectionSetupTiplete5.RRCConnectionSetupCoAttachRequestPDNconnectivityrequest6.InitialUEmessageAttachRequestPDNconnectivityrequest7.MMES-GW

13、8.DAttachReDWNLINKNASTRANSPORTjectPDNconnectivityreject)9.DLlnformationTansfeAttachRejectPDNconnectivityreject)IO.UECONTEXTRELEASECOMMAND11.RRCConnectionReleose12.UECONTEXTRELEASECOMPLETE # # # #l）如果是ESM過(guò)程導(dǎo)致的拒絕（比如默認(rèn)承載建立失?。艜?huì)帶PDNCONNECTIVITYREJECT消息；EMM層拒絕，只有ATTACHREJECT消息。 # 常見(jiàn)的拒絕原因有：IMSI中的MNC與核心網(wǎng)配

14、置的不一致。1.2.2.3eNB未等到Initialcontextsetuprequest消息UEcNBEPC開(kāi)機(jī)后先進(jìn)行小區(qū)選擇，接收系統(tǒng)信息，然后開(kāi)始附若I.RAPreamble2.RAResponse3.RRCConncctionRcqucst4.RRCConnectionSetup5.RRCConncctionSctupConplctc(包含(AttachRequest、PDNconnectivityrequest消息)啟動(dòng)T3410(I5s)(包含AttachR(6.InitialUEnlessagequest、PDNconnectivityrequest?肖X!、)7.Idcnti

15、ty/Authpntication/Sccurity8建琥認(rèn)EPS朮我等)定時(shí)器超時(shí)13.RRCConnectionReleae冷止T3410.如處可繭發(fā)，則啟動(dòng)T34ll(IQs)T34ll超時(shí)，IE新發(fā)送a【(achrequest9.Initialcontextsetuprequest-IX #1.2.2.4RRC重配消息丟失或者沒(méi)收到RRC重配完成消息或者eNB內(nèi)部配UE的安全參數(shù)等失敗 /I機(jī)用先14冇水區(qū)遙并孩枚系統(tǒng)信息然后開(kāi)怡附著eNBI.RAPreamble2.RAResponse3.RRCConnectionRequest4.RRCConnectionSetup（包含5.RRC

16、ConnectionSetupConAttachRequest、PDNconnectivitpleteyrequeslifj息)啟T34io(15s)6.InilialUEmessage(包含AliachquestPDNconnectivityreque兒消息)7.Idcmi(y/Au(hcnlkation/SccurityActivate10.UECapabilityEnquiry(s耀立戲認(rèn)EPS脈牧答Initialconiextseluprequest(包含AttachAccept.defaultEPSbearercontextrequjst)Acti11.UECapabilitylnf

17、onnation1-.UECapabilityInfoIndication13.SecurityModeCommand14.SecurityModeComplete15.RRCConneclionReconfiguralio1包含AttachAcccpl、aledefaultEPSbearercontextrcqicsl)I6Inilialconicxlsclupfailure17.UECONTEXTRELEASERLQUEST19.1(i8.更紡點(diǎn)拔)ECONTEXTRELEASECOMM/ND20.RRCConncctionRclcascffibT3410,如果可錶發(fā)則啟功JT341I,I

18、21.LECONTEXTRELEASECOMPL:n:(T341闔時(shí)，重新發(fā)送.attachrequest # 1.3UE發(fā)起的servicerequest流程1.3.1正常流程UE在IDLE模式下，需要發(fā)送業(yè)務(wù)數(shù)據(jù)時(shí)，發(fā)起servicerequest程，流程圖如下： #cNBEPC # #RAPreambleRAResponseRRCConneclionRcqucslRRCConneciionSeiupRRCConneciionSeui|)Comphle(包含ServiceRequest泊息)6.Initiallbmessage(包含ServiceRequestiff.&)Aulhcniic

19、alion # # # #SIAP:Initial(oiiicxiSclupRejueslUECapabililyEnquir)*10.1/ECapabililyInformation11.12.SecurityMixleConiniandUECapabilityInfiIndicalioi # # # #13.SecurityModeConipkle14RRCConnectionReconfigurationRCConncchonRcconfigurationConplctc # # # #16.SIponseAP:InilialContextSetupReFirstUplinkDataHi

20、rsiDomilinkDala # #tnt.UeeA17.inac：Mty丿UEConiextReleaseReques(Cause)UEContexlReleaseComm;19.RRCConnectionRelease20.UEContextReleaseComplc # # # #1-3.2異常流程1.3.2.1RRC連接建立失敗處理同3.321。 # 1.3.2.2核卜網(wǎng)拒絕 # # #6dleservicerequest丿J:丿1.RAPreambleRAResponseRRCConnectionRequestRRCConnectionSetup5.RRCConnectionSet

21、upCompkite(servicerequest6.InitialUEmessageservicerequest7.MMES-GW8DOWNLINKNASTRANSPO(servicereject) # # # 9.DLlnformationTansferservicereject)11.RRCConnectionRelease丨0UECONTEXTRELEASECOMMAND12.UECONTEXTRELEASECOMPLETEeNB未等到Initialcontextsetuprequest消息處理同3.323,區(qū)別在于servicerequest過(guò)程失敗沒(méi)有重發(fā)。RRC重配消息丟失或者e

22、NB內(nèi)部配置UE的安全參數(shù)失敗或者沒(méi)有建立起來(lái)一個(gè)非GBR承載同3.324,區(qū)別在于servicerequest過(guò)程失敗沒(méi)有重發(fā)。 #1.3.2.5eNB建立專用承載失敗當(dāng)amch成功，建立一個(gè)專用承載后，如果RRC連接釋放進(jìn)入了IDLE,下次UE發(fā)起數(shù)據(jù)時(shí)會(huì)發(fā)起servicerequest,該過(guò)程會(huì)為默認(rèn)承載和專用承載建立對(duì)應(yīng)的DRB等參數(shù)。如果eNB建立專用承載失敗，則冋復(fù)給核心網(wǎng)Initialcontextsetupresponse,帶失敗列表，告知核心網(wǎng)專用承載建立失敗，核心網(wǎng)會(huì)本地去激活該專用承載；同時(shí)RRCConnectionReconfiguration消息也不會(huì)帶該專用承載的D

23、RB,UE收到后發(fā)現(xiàn)該專用承載對(duì)應(yīng)的DRB沒(méi)有建立起來(lái)，也會(huì)本地去激活該承載，這樣UE和核心網(wǎng)承載保持一致。流程圖同341正常流程。1.3.2.6eNB建立默認(rèn)承載失敗場(chǎng)景同上，當(dāng)建立的這個(gè)專用承載也為非GBR承載時(shí)，eNB可能會(huì)成功建立該專用承載，而失敗建立跌認(rèn)非GBR承載，這樣口I復(fù)給核心網(wǎng)Initialcontextsetupresponse,帶失敗列表，核心網(wǎng)發(fā)現(xiàn)默認(rèn)承載建立失敗時(shí)，會(huì)本地delach該UE；同時(shí)RRCConnectionReconfiguration消息也不會(huì)帶該默認(rèn)承載的DRB,UE收到后發(fā)現(xiàn)默認(rèn)承載對(duì)應(yīng)的DRB沒(méi)有建立起來(lái)，也會(huì)本地去激活該默認(rèn)承載,以及關(guān)聯(lián)的專用

24、承載，從而本地detach（只有一個(gè)默認(rèn)承載時(shí)），這樣UE和核心網(wǎng)承載保持一致。流程圖如2 # 1.RAPreamble # # # #RAResponseRRCConncctionRcqucstRRCConnectionSetupRRCConnectionSetupCoinpl:te（包含ServiceRequest消息）InitialUEmessage（包含ServiceRequest消息）Authcniication # # # #InitialContextSetupReques9.UECapabi1ityEn|uiryUECapabilitylnforination11.UECapa

25、bilityInfoIndicatio1Sccuri（yModcCoininandSecuritvModeCoinplete14RRCConnectionReconfiguration # # #15.IDLE下發(fā)起的不設(shè)置“active“標(biāo)識(shí)的正常TAU流程圖如下： # UEcNBHIXIDLE卜當(dāng)UE進(jìn)入的TAI不在探存的TAI甌內(nèi) # #1.RAPreambleRAResponseRRCConncclionRcqucstRRCConnectionSetup.RRCConncctionSclupComplct（包含TAUrequest） # # # #InitialUEmessage（包舎

26、TAUrcqucsOAuthenticatioi/SecurityUE上卜力夯9.Initialcontext*etuprequest（包會(huì)TAUAccept）10.UECapabiIityEnquiryUECapabililyInformation # # # #UECapabilityTnfoIndication13.SecurityModeCommandSecurityModeCompleteRRCConncctionRcconfiguratioii（包含TAUAccept）16.RRCConncctionRcconfigurationCompIctc.Initialcontextset

27、upresponse18.ULInformationTransfcr（包含TAUComplete）19.UPLINKNASTRANSPORT（包舍TAUComplete）FirstUplinkDita # # # #FirsiDownlinkData20. #1.5.1.2CONNECTED下發(fā)起的 # # # #rconnectedFM1UEi進(jìn)入的TAI不在J保存的TATIisl內(nèi)丿eNBEPC # # # #ULInformationTransfcr（包含TAUrequest消息） # # # #UPLINKNASTRANSPORT（包含TAUrequest消息） # # # #r3.M

28、ME間更新IUE上下文等 # # 4.DOWNLINKNASTRANSPOFT（包含TAUAccept消息）DLInformationTransfer（包含TAUAccept消息）ULInformationTransfcr（包含TAUComplete消息）7.UPLINKNASTRANSPORT（包含TAUComplete消息）說(shuō)明：1）如果TAUaccept未分配一個(gè)新的GUTI,則無(wú)過(guò)程6、7；2）切換下發(fā)起的TAU,完成后不會(huì)釋放NAS信令連接；3）CONNECTED下發(fā)起的TAU,不能帶”active”標(biāo)識(shí)。1.5.2異常流程異常流程同3.4.2。1-6去附著1.6.1關(guān)機(jī)去附著UE關(guān)

29、機(jī)時(shí)，需更發(fā)起去附著流程，來(lái)通知網(wǎng)絡(luò)釋放其保存的該UE的所有資源,流程圖如下：用戶關(guān)機(jī),發(fā)起去附著EPC # # # #如果在IDLE下，先發(fā)起師機(jī)接入和RRC連接建立過(guò)程l.NAS:DetachRequest(Switchoff)本地消空所有EPS承載和RB資源2地淸空該UE的所,EPS承載和TEID資參2.3.UEContextReleaseCommandUEContextReleaseComple # # # 說(shuō)明:IDLE和CONNECTED下發(fā)起的區(qū)別同上曲TAU的區(qū)別：如果是非關(guān)機(jī)去附肴，則會(huì)收到MME的DetachAccept響應(yīng)消息和eNB的RRCConnectionRelea

30、se消息。1.6.2非關(guān)機(jī)去附著1.6.2.1IDLE下發(fā)起的非關(guān)機(jī)去附著EPCtheEPScapabilityoftheUEisdisabledI.RAPreambleRAResponseRRCConnectionRequestRRCConnectionSetupRRCConneclionSelupComplet;（包含DetachRequest）木地清空所有EPS祇我和RB資源6.InitialUEmessage（illIVDetachRequest）7.Securty8.本地洽空該UE的所有EPS承載和TEII）論源DOWNLINKNASTRANSPORT（包含DetachAccept）

31、9.DLInformationTransfer（包含DeUichAccept）10.UECONTEXTRELEASECOMMAND11.RRCConnectionRelease12UECONTEXTRELEASECOMILETE乂進(jìn)入IDLE模式 #1.6.2.2CONNECTED下發(fā)起的非關(guān)機(jī)去附著theEPScapabilityoftheUEisdisabledEPC1.ULInformationTransferDetachrequest)2.UPLINKNASTRANSPORTDetachrequestUETEID3DOWNLINKNASTRANSPORT(DetachAccept)4.

32、DLlnformationTransferDetachAccept5UECONTEXTRELEASECOMMAND6.RRCConnectionRelease7.JECONTEXTRELEASECOMPLETE1-7切換流程當(dāng)UE在CONNECTED模式下時(shí)，eNodeB可以根據(jù)UE上報(bào)的測(cè)量信息來(lái)判決是否需要執(zhí)行切換，如果需要切換，則發(fā)送切換命令給UE,UE不區(qū)分切換是否改變了eNodeB非竟?fàn)幥袚Q流程圖如下： # UESourceeNBTargeteNBEPC # #1.Measurementcontrol(RRC) # # # #PacketdataPacketdata # # # #U

33、LallocationPDCCH2.MeasurementReport(RRCHORequest #5.RRCConnectionReconfiguration(HOCommand)4.HORequestAckDuffereiDeliverpacketsto.TeNB6.SNStatusTiBnsferBufferpacketsfromSeNB7.RandomActssPreamble8.RandomAccResponse9.RRCConrlectionReconfigurationCConfinjmplete(HOi)PathSwitchFlushDLBuffer10.ReleaseReso

34、urce # 1-8專用承載建立流程1.8.1正常流程專用承載建立可以I11UE或者M(jìn)ME主動(dòng)發(fā)起，cNB不能主動(dòng)發(fā)起，并口.只能在connected下發(fā)起該流程。connec-ed6ReNBUL-nfomaionTansfeBeareresourcem=ocaionequesc5RRCCOnnecHonReconfiguat一Aciiva叵ModifydedicatedEPSconCDxirequestRcconneaonReconfigurationcEPC2UP匚NKNASTRANSPORTBeaeresourceequesia-oco-nURABSETUP、MOD_FYREQUESTA

35、CHVaieModifydedicatedEPSb2aeconQxiequesuQmp-eo7ERABsetup、mod_fyRESPONSE8UL-nfomationTansfeIAciivaie/ModifydedicatedEPSbeaeconlol$accepi7up-inkDmoraUPLJNKNASTRANSPORTAciivaie/ModifydedicatedEPSCTconCDxiacceptDown-inkDmor養(yǎng)：1)與汩油MMEZk&盛3沬曲fl0至*呼淫注蛙遐72“ #2）UE發(fā)起的承載建立流程，核心網(wǎng)可以冋復(fù)承載建立、修改流程;3）可以同時(shí)建立多個(gè)專用承載，但H前

36、還不支持。 # # # 1.8.2異常流程1.8.2.1核心網(wǎng)拒絕UEconnected卜無(wú)匹配的分類器1.ULInformationTransfer（包HBearerresourceallocationrequest)2.UPLINKNASTRANSPORT(包含Bearerresourceallocationrequest)3.承載分配請(qǐng)求，被拒絕4.(包DOWNLINKNASTRANSPORTptBearerresourceallocationreje(t)5.DLTnformationTransfer(包含Bearerresourceallocationreject)如果拒絕原因值是u

37、nknownEPSbearercontext*,UE會(huì)本地去激活存右泊勺默認(rèn)承載。1.8.2.2eNB本地建立失?。ê诵木W(wǎng)主動(dòng)發(fā)起的建立）如果eNB建立失敗，會(huì)冋復(fù)E-RABSETUPRESPONSE,帶失敗建立的承載列表,并帶原因值，核心網(wǎng)應(yīng)該根據(jù)原因值處理（H前eNB的實(shí)現(xiàn)是：如果eNB本地建立失敗，即還沒(méi)有給UE發(fā)送RRC重配消息，這時(shí)eNB會(huì)發(fā)送NASNONDELIVERYINDICATION給MME）。但廿前核心網(wǎng)沒(méi)有査看原因值，都給UE下發(fā)了DeactivateEPSbearercontextrequest消息（與協(xié)議不符），UE查找不到該承載，也冋復(fù)DeactivateEPSbe

38、arercontextaccept #UEcNBEPC # # # #1承載分配請(qǐng)求2.E-RABSETUPREQUEST(包含A(tivatededicatedEPSbearercontexrequest)3.E-RABSETUPRESPONSEC；i；E-RABFailedList,causeMRacioresourcesnotavailable*1) # # # #4.本地鮮放朮我 # 1.8.2.3eNB未等到RRC重配完成消息，回復(fù)失敗 # # # #EPC # # # #I.承載分配譴求（包含A（trequest)2.E-RABSETUPREQUESTtivatcdedicated

39、EPSbearercontc # # # #（包onx(request)3.RRCConnectionReconfiguratActivatededicatedEPSbearerconte # # # #4./RRCConnectionReconfiguratio/iCox定時(shí)器超時(shí)nplete5.E-RABSETUPRESPONSE帶ERABFailedList,causeMFlilureintheRadioInterfaceProcedure)7.1ECONTEXTRELEASEREQUB # # #8更新承載ECONTEXTRELEASECOMM/ND10.RRCConnectionRe

40、leaseETElI.IJECONTEXTRELEASECOMPLeNB未收到RRC重配完成消息時(shí)，會(huì)給核心網(wǎng)發(fā)UEI-下文釋放請(qǐng)求消息。1.8.2.4UENAS層拒絕如果是UE的NAS層拒絕，則核心網(wǎng)收到后會(huì)給eNB發(fā)送E-RAB釋放消息，來(lái)釋放剛剛建立的S1承載，此時(shí)不帶NASPDUocNB收到消息后，發(fā)RRC重配給UE來(lái)釋放剛建立的DRB參數(shù)。 1承敎分配請(qǐng)求（包羊（包含Act2.E-RABSETUPREQUESTvalededicatedEPSbearerconlexinAciivatcdedicatedEPSbearercontextrequesi)3.RRCConnectionRe

41、configuraticRRCConnectionReconfigurationC)mplete5.E-RABSETUPRESPONSErequest)6.UE側(cè)NAS層承我建立失畋7.ULInformationTransfer(tilrActivatededicatedEPSbearerconte?treject)（包含Aciv:IUPLINKNASTRANSPORT(cdedicatedEPSbearerconicxtrcicc【)10.E-RABRELEASECOMMAND(不含NASPDU)1RRCConncctionRcconflguratioi(帶釋放DRB列表)12.RCConn

42、ectioiiReconfiguratioiiComplete1：E-RABRELEASERESPONSI # 1.8.2.5上行亶傳NAS消息丟失connectedTJL匹配的分類器（包I.ULInformalionTranscBearerresourceallocationrequest)2.UPLINKNASTRANSPORT(Bearerresourceallocalionrequ:sl)3.承栽分配請(qǐng)求（包含Act4.E-RABSETUPREQUESTvatededicatedEPSbearercontextequest)5.RRCConnectionReconfigurati(包令

43、ActivatededicatedEPSbearercontexo|nrequest)6丨IRCConnectionReconfigunuionConplete7.E-RABSETUPRESPONSE(包,8.ULInformationTransfcrVActivatededicatedEPSbearerconte:taccept)定時(shí)器超時(shí).（包含（包令9.POWNLINKNASTRANSPORT(包含ActivalededicatedEPSbearercontextrequest)10.DLInformationTransferActivatededicatedEPSbearercontc

44、xII.ULInforniationTransferActivatededicatedEPSbearercontextI(包含Actitrequest)accept)2.ULLINKNASTRANSPORTvatededicatedEPSbearercontextaccept)說(shuō)明：如果核心網(wǎng)沒(méi)有收到UE冋復(fù)的NAS消息，會(huì)重發(fā)請(qǐng)求消息，重發(fā)4次后,如果還沒(méi)收到應(yīng)答則放棄。 #1.9專用承載修改流程1.9.1正常流程 # # 專用承載修改可以111UE、MME主動(dòng)發(fā)起，不能山eNB主動(dòng)發(fā)起，只能在connected下發(fā)起該流程。流程圖如下:修改QoSUEeNBEPCconnectedb(&改個(gè)

45、專川EPS承載I.ULInformationTransfer（包Bearerresourcemodificationrequest)2（包含氏UPLINKNASTRANSPORTarerresourcemodificationrequcst)4.E-RABSE(包含ActiFUP/MODIFY/RELEASECOMMANDatefodify/DeactivateEPSbeamcontextrequest)（包5.RRCConncctionRcconfiguratiopVActivate/Modify/DeactivateEPScontextrequest)bearerCConnectionRe

46、conflgurationComplete7.E-RABSETUP/MODIFY/RELEASERESPONSE8.ULInformationTransfer(包含/ctivatefodify/DeactivateEPSbe;rercontextaccept)9.(包含AcUPLINKNASTRANSPORTivale/Modify/DeactivateEPSarercontextaccept)io脈我修改響應(yīng)說(shuō)明:1)MME主動(dòng)發(fā)起的承載建立/修改/樣放無(wú)步驟1、2：2)cNB主動(dòng)發(fā)起的釋放,無(wú)步驟1,步驟2改為發(fā)送E-RABRELEASEINDICATION消息給MME；1.9.1.23)

47、UE發(fā)起的承載修改流程,不修改QoS,只修改TFT8nnecied下修改個(gè)專用EPS承我(包核心網(wǎng)可以冋復(fù)承載建立、修改、釋放流程。eNBEPC1.ULInformationTransferVBearerresourcemodificationrequest)2(包含BUPLINKNASTRANSPORTdarerresourcemodificationrequcSt)4.DO(包含NNLINKNASTRANSPORTdifyEPSbearercontextrequest)5DLInfonnationTransfer(色含ModifyEPSbearercontextrequ(fill6.ULI

48、nformationTransferpModifyEPSbearercontextaccept)7.UPLINKNASTRANSPORT(包個(gè)ModifyEPSbearercontextaccept)說(shuō)明：不修改QoS,只修改TFT參數(shù)時(shí)，為上下行直傳消息，與eNB無(wú)關(guān)。1.9.2異常流程1.9.2.1核心網(wǎng)拒絕UEconncclcd卜修改個(gè)專用EPS承載l.ULInforniationTransfcrBearerresourcemodificationrequest)2（包含BUPLINKNASTRANSPORTmodificationearerresourcerequcst)3.承載修改請(qǐng)求.被拒絕4.(包含BearerDOWNLINKNASTRANSPORTresourcemodiHcationreject)DLInformationTransfer（包含Bearerresourcemodificationrejcct)如果拒絕原因值是HunknownEPSbearercontextH,UE會(huì)本地去激活存右的專用承載。1.9.2.2eNB回復(fù)失敗eNB冋復(fù)失敗區(qū)分為：cNB本地失敗，沒(méi)有給UE發(fā)送RRC重配消息;eNB未收到RRC重配完成消息，冋復(fù)失敗。以上一過(guò)程同3.92