Gsm呼叫流程绝对经典

GSM呼叫流程1整理课件目的和内容目的介绍GSM正常的呼叫流程〔空中接口、A-bis接口和A接口〕介绍局部常见的异常中断的流程内容GSM网络协议介绍GSM逻辑信道介绍无线链路建立流程〔RadioandLinkEstablishmentProcedure〕TCH正常分配流程〔NormalAssignmentProcedure〕主叫流程〔OriginatingCall〕被叫流程〔TerminatingCall〕位置更新流程〔LocationUpdating〕切换流程〔HandoverProcedure〕呼叫释放流程〔CallReleaseProcedure〕信道释放流程〔ChannelReleaseProcedure〕2整理课件GSM协议层数无线网络优化主要关心第三层的信令无线网络优化主要关心DTAP、RSL的信令无线网络优化主要关心DTAP、BSSMAP和局部SCCP的信令DTAPRSLOMLGSM网络协议3整理课件Layer3介绍RR:无线资源管理〔RadioResourceManagement〕由MS、BTS和BSC控制功能举例Paging管理〔PagingManagement〕加密管理〔CipheredModeManagement〕频点分配〔FrequencyRedefinition〕信道分配〔DedicatedChannelAssignment〕切换〔HandoverManagement〕测量和功率控制〔MeasuresandPowerControl〕MM:移动性管理〔MobilityManagement〕由MS和MSC/VLR控制功能举例鉴权和身份识别〔Authentication/IdentificationProcedures〕位置更新〔LocationUpdating〕IMSIAttach/DetachGSM网络协议4整理课件CC:呼叫控制〔CallControl〕由MS和MSC控制功能举例呼叫处理和路由〔Callprocessingandrouting〕双音多频〔DTMFFacilities〕短消息效劳〔ShortMessageService〕附加效劳〔SupplementaryService〕GSM网络协议5整理课件呼叫流程中常用的逻辑信道PCH寻呼信道〔PagingChannel〕RACH随机接入信道〔RandomAccessChannel〕AGCH接入认可信道〔AccessGrantChannel〕SDCCH独立专用控制信道〔Stand-aloneDedicatedControlChannel〕SACCH慢联系控制信道〔SlowAssociatedChannel〕TCH话务信道〔TrafficChannel〕FACCH快联系控制信道〔FastAssociatedControlChannel〕GSM呼叫流程中常用的逻辑信道PCHRACHAGCHSDCCH+SACCHTCH/FACCH+SACCH6整理课件定义与网络间建立一个无线链路，用于信令传送包括以下四个步骤Paging过程〔PagingProcedure〕〔仅用于被叫流程中〕随机接入过程〔RandomAccessProcedure〕立即分配过程〔ImmediateAssignmentProcedure〕SCCP联接建立过程〔SCCPConnectionEstablishmentProcedure〕当需要与网络发生联系时，必须要先建立无线链路和A接口的信令连接无线链路建立流程7整理课件MSBTSBSCMSCChannelRequestChannelRequiredChannelActivation〔SD〕ChannelActAck〔SD〕ImmediateAssignmentCommandUIImmAssignment/ImmAssExtST9103ET9103ST3126ET3126ST3101SABM[L3Info]EstInd[L3Info]SCCPConRqrd[L3]SCCPConnConfirmET3101ST9105ET9105UA[L3Info]〔RACH〕〔EstCause，RndNbr〕〔EstCause，RndNbr，TA〕RACH_TA_Filtering〔TA，BS/MS_TxPwr-->Max，Chann〕Timer；S--Start；E--EndEntity信令消息空中接口Abis接口A接口〔RndNbr，TDMAFrameNbr，Chan，TA〕〔AGCH〕同时对两个MS分配SDCCH〔SDCCH〕BSC开始对MS发出的上行DTAP消息排队〔如CMServAbort消息〕。如果收到MS发出的ClassmarkChange消息，BSC会在SCCP连接完成后发ClassmarkUpdate消息给交换机如CMServReq，PagRes，LocUpdateReq等SetAsynchronousBalanceMode。在任何新信道登陆时均会有SABM过程UnnumberedAck无线链路建立流程8整理课件无线链路建立流程——异常情况对不同的呼叫类型有不同的等待时间：WI_EC/CR/OC/OP.(OP主要指LU,被叫没有相应等待时间)SDCCH拥塞如果BSC在收到ChannelRequired时，相应小区没有空闲的SDCCH，BSC将会如果小区参数En_Imm_Ass_Rej=“True〞，那么发ImmediatelyAssignmentReject否那么忽略ChannelRequired消息T9103超时BSC发RFChannelRelease消息到BTSBSC收到ChannelActivationNAck消息BSC内部释放BTS的相应无线信道(没有任何消息在Abis接口上传送)T3101超时Layer3无法建立BSC发RFChannelRelease到BTST9105超时BSC通过呼叫释放过程〔CallReleaseProcedure〕释放原先建立的SDCCH连接在A接口，BSC向MSC发SCCP释放请求在RF局部，BSC向和BTS发信道释放消息

仅在BSC内部资源表中释放，在Abis上没有信令传送当信道激活不成功时触发的BTSRFChanRel不包含PhysContReq过程9整理课件BSC收到EstablishIndication消息，但消息中不含Layer3InformationBSC向和BTS发信道释放消息Abis上的其它异常中断消息的处理BSC收到ErrorIndicationCause为:“T200Expiry〞:监视SABM和UA过程“UnsolicitedDMResponse〞(发生在Disconnect过程中〕“SequenceError〞释放：A接口上，BSC发ClearRequest“RadioInterfaceFailure〞到交换机BSC向和BTS发信道释放消息BSC收到ConnectionFailureindication(Cause:RadioLinkFailure)在A接口上，BSC发ClearRequest“RadioInterfaceFailure〞到交换机BSC向BTS发RFChannelRelease消息BSC收到ReleaseIndication当收到发出的DISC消息A接口上，BSC发ClearRequest“RadioInterfaceFailure〞到交换机BSC向和BTS发信道释放消息无线链路建立流程——异常情况10整理课件MSBTSBSCMSCAuthenticationReqCipheringModeCmdAuthenticationReqAuthenticationReqAuthenticationRespAuthenticationRespAuthenticationRespEncryptionCommandCipheringModeCmdCipheringModeCmpCipheringModeCmpCipheringModeCmpTMSIReallocCmdTMSIReallocCmdTMSIReallocCmdTMSIReallocCmpTMSIReallocCmpTMSIReallocCmpAuthenticationCipheringTMSIReallocST3260ET3260*AuthenticationReject*IdentificationIdentificationRequestST3270ET3270IdentificationRequestIdentificationRequestIdentificationResponseIdentificationRespIdentificationResponseST3250ET3250〔RAND〕〔SRES〕RAND与Ki经过A3算法得到SRES；经过A8算法得到Kc比较SRES〔IMSI〕选择加密算法〔PermittedAlg，Kc〕准备解密接收〔Alg，Kc〕〔Alg〔A5算法〕〕开始加密发射和解密接收如正确解密接收，那么下条消息加密发射已加密的消息〔TMSI〕VLR从HLR处得到RAND/SRES/Kc鉴权、身份识别、加密、TMSI重新分配过程11整理课件鉴权过程中的异常情况鉴权失败如果鉴权过程中使用TMSI，网络将启动身份识别过程。如果送上来的IMSI与VLR中TMSI所对应的IMSI不一致，那么重新进行鉴权如果鉴权过程中已经使用IMSI，那么网络发AuthenticationReject消息。这个SIM将被认为是无权的T3260超时第一次超时，网络将重发鉴权请求；第二次超时，网络将释放该MM连接身份识别过程中的异常情况T3270超时第一次超时，网络将重发身份识别请求；第二次超时，网络将释放该MM连接TMSI重新分配过程中的异常情况T3250超时第一次超时，网络将重发TMSI重新分配请求；第二次超时，网络将释放该MM连接鉴权、身份识别、加密、TMSI重新分配过程——异常情况12整理课件定义分配TCH的过程特殊情况排队〔Queuing〕直接重试〔DirectedRetry〕TCH分配过程13整理课件MSBTSBSCMSCChannelActivationTCHSABM(FACCH)ChannelActivationAck.AssignmentCommandAssignmentCommandAssignmentRequestPhysicalContextRequestPhysicalContextConfirmEstablishIndicationUAAssignmentCompleteAssignmentCompleteAssignmentCmpRFChannelRelease(SD)RFChannelReleaseAck.STrr1ETrr1ST9108ET9108ST9103ET9103ST3107ET3107〔ChnType，Priority，CIC，DLDTX，QueuingFlag〕〔TA，MS/BS_TxPwr〕〔SDCCH〕〔TA，MS/BS_TxPwr〕〔MA，TS，HSN，MAIO，MS_TxPwr〕占用TCH时，如需传送信令，那么通过StealingFlag将TCH转换成FACCH一般情况下，在RF信道释放前都有PhysicalContextReq过程TCH分配过程14整理课件MSBTSBSCMSCSABM(FACCH)ChannelActivationHOCMDAssignmentRequestPhysicalConReqChan.Act.Ack.HODetectionUAPhys.InfoAssignmentCmpST11ST3103QueuingIndicationET11Atthistime,aTCHbecomefreeTCH拥塞和排队AssignmentRequestST11QueuingIndicationET11AHandoveralarmisraised.AtargetBTSisselectedHOCMDHOAccessST9103ET9103TTSTTEstablishIndicationTTHOCMPTHOCMPST3124ET3124ET3103直接重试如果QueuingInd=True或Queuing_Anyway=True。〔当Queuing_Anyway时T11_Forced取代T11TCH分配过程——排队和直接重试15整理课件TCH拥塞情况不允许排队或队列已满在A接口BSC发AssignmentFailure"NoRadioResourceAvailable"呼叫进入队列，但T11时间内没有TCH空出在A接口BSC发ClearRequest"NoRadioResourceAvailable"呼叫被优先级更高的呼叫挤出队列在A接口BSC发AssignmentFailure"NoRadioResourceAvailable〞T9108超时:BTS对physicalcontextrequest没有响应之后的ChannelActivation消息中将不带TA和及BTS的发射功率信息T9103超时:ChannelActivation没有回应A接口上BSC发AssignmentFailure"RadioInterfaceFailure"BSC向BTS发RFChannelRelease消息TCH分配过程——异常情况16整理课件BSC收到ChannelActivationNegativeAcknowledge消息ChannelActivationNegativeAcknowledge有以下几种原因:ChannelAlreadyActivated(CAA):BSC向和BTS发信道释放消息RadioResourceNotAvailable(RRNA)-Protocolerror(PE):BSC内部释放Requestedtranscodingratenotsupported(RTRNS):BSC内部释放Encryptionalgorithmnotimplemented(EANI):BSC内部释放O&MIntervention(OI):BSC内部释放在A接口上发AssignmentFailure消息对于收到ChnavNegAck原因为EANI的情况，AssignmentFailure的cause为"CipheringAlgorithmnotsupported"其它情况，AssignmentFailure的cause为"RadioInterfaceFailure"TCH分配过程——异常情况17整理课件在原来的信道上〔如SDCCH信道〕收到AssignmentFailure消息收到AssignmentCommand后，在新信道上发SABM消息，BTS收到后向发UA消息。但可能由于空中接口原因，没有收到UA消息。尝试N200次均未成功。将会回到原来的信道。并发AssignmentFailure消息BSC收到该消息后在A接口发AssignmentFailure"ReversiontoOldChannel"BSC向BTS发RFChannelRelease消息，释放新信道AssignmentCommand的内容有误发现AssignmentCommand消息中内容有误，发AssignmentFailure消息到BSCBSC收到该消息后在A接口发AssignmentFailure"ReversiontoOldChannel"BSC向BTS发RFChannelRelease消息，释放新信道T3107超时BSC在A接口发AssignmentFailure“RadioInterfaceMessageFailure〞，并开始T9110计时BSC向BTS发RFChannelRelease消息，释放新老信道MSC向BSC发ClearCommand消息〔呼叫释放〕，并停止T9110一般情况下，交换机收到该消息后发DISC〔tempfail〕TCH分配过程——异常情况18整理课件直接重试中的异常情况没有CandidatecellBSC在A接口发AssignmentFailure“NoRadioResourceAvailable〞ChannelActivation过程中T9103超时BSC在A接口发AssignmentFailure“RadioInterfaceFailure〞BSC向BTS发RFChannelRelease消息BSC收到ChannelActivationNegativeAcknowledge消息ChannelActivationNegativeAcknowledge有以下几种原因:ChannelAlreadyActivated(CAA):BSC向和BTS发信道释放消息RadioResourceNotAvailable(RRNA)-Protocolerror(PE):BSC内部释放Requestedtranscodingratenotsupported(RTRNS):BSC内部释放Encryptionalgorithmnotimplemented(EANI):BSC内部释放O&MIntervention(OI):BSC内部释放在A接口上发AssignmentFailure消息对于收到ChnavNegAck原因为EANI的情况，AssignmentFailure的cause为"CipheringAlgorithmnotsupported"其它情况，AssignmentFailure的cause为"RadioInterfaceFailure"TCH分配过程——异常情况19整理课件T3103超时:没有收到HOFailure或HOComplete消息BSC在A接口发AssignmentFailure“RadioInterfacemessageFailure〞BSC向和BTS发信道释放消息，释放新老信道收到发来的HOFailure消息BSC在A接口发AssignmentFailure“ReversiontoOldChannel〞消息BSC向BTS发RFChannelRelease消息，释放新信道Abis上的其它异常中断消息的处理BSC收到ConnectionFailureIndicaiton消息Cause为:“RadioInterfaceFailure〞:无线链路超时引起的释放释放：A接口上，BSC发ClearRequest“RadioInterfaceFailure〞到交换机BSC向BTS发RFChannelRelease消息BSC收到ErrorReport消息BSC收到ErrorIndication消息BSC收到ReleaseIndication消息A中继信道拥塞或不可用情况TCH分配过程——异常情况20整理课件主叫过程〔非OACSU情况〕MSBTSBSCMSCCallProceedingESTIN(CM_Serv_Req)RRConnectionEstablishmentRRConnectionEstablishmentRRConnectionEstablishmentAuthenticationProcedureAuthenticationProcedureAuthenticationProcedureCipheringProcedureCipheringProcedureCipheringProcedureTMSIReallocProcedureTMSIReallocProcedureTMSIReallocProcedureSETUPSETUPSETUPCallProceedingCallProceedingAssignmentProcedureAssignmentProcedureAssignmentProcedureAlertingAlertingAlertingConnectConnectConnectConnectAck.ConnectAck.ConnectAck.SpeechCM_Serv_ReqOffAirCallSetup〔calledpartynbr〕先建立TCH，再接通B侧信道。Alerting在TCH上发送〔CMServType，MobileID，Classmark2，Priority，〕SDCCHTCH21整理课件MSBTSBSCMSCCallProceedingESTIN(CM_Serv_Req)RRConnectionEstablishmentRRConnectionEstablishmentRRConnectionEstablishmentAuthenticationProcedureAuthenticationProcedureAuthenticationProcedureCipheringProcedureCipheringProcedureCipheringProcedureTMSIReallocProcedureTMSIReallocProcedureTMSIReallocProcedureSETUPSETUPSETUPCallProceedingCallProceedingAssignmentProcedureAssignmentProcedureAssignmentProcedureAlertingAlertingAlertingConnectConnectConnectConnectAck.ConnectAck.ConnectAck.SpeechCM_Serv_ReqSDCCHTCH先接通B侧信道，再建立TCH。Alerting在SDCCH上发送主叫过程〔OACSU情况〕22整理课件MSBTSBSCMSCCallConfirmedESTIN(PagingResp)RRConnectionEstablishmentRRConnectionEstablishmentRRConnectionEstablishmentAuthenticationProcedureAuthenticationProcedureAuthenticationProcedureCipheringProcedureCipheringProcedureCipheringProcedureTMSIReallocProcedureTMSIReallocProcedureTMSIReallocProcedureSETUPSETUPSETUPCallConfirmedCallConfirmedAssignmentProcedureAssignmentProcedureAssignmentProcedureAlertingAlertingAlertingConnectConnectConnectConnectAck.ConnectAck.ConnectAck.SpeechPagingResponsePagingPagingCommandPagingRequestST3113ET3113PagingGroup的个数〔N〕：由BS_AG_BLKS_RES和BS_PA_MFRMS决定;MS的PagingGroup=(IMSImod1000)modN;MS只监听自己对应的PagingGroup的PagingReq消息〔MSID〔TMSI/IMSI〕，CellID〔LAC/LAC+CI〕〕〔MSID〔TMSI/IMSI〕，PagingGroup〕〔MSID〔TMSI/IMSI〕〕〔最多可同时发4个TMSI〕〔MobileID，Classmark2，Priority，〕〔callingpartynbr〕被叫过程23整理课件Paging失败T3113超时如果T3113超时，PagingResponse消息没有收到，网络会重发Paging消息，并重新开始T3113计时。重试的次数在交换机中定义。24整理课件MSBTSBSCMSCClearCMDESTIN(LocUpReq)RRConnectionEstablishmentRRConnectionEstablishmentRRConnectionEstablishmentAuthenticationProcedureAuthenticationProcedureAuthenticationProcedureCipheringProcedureCipheringProcedureCipheringProcedureTMSIReallocProcedureTMSIReallocProcedureTMSIReallocProcedureLocUpAcceptChannelReleaseDeactivateSACCHDISCReleaseIndicationUARFChReleaseLocUpReqLocUpAcceptLocUpAcceptChannelReleaseRFChReleaseAckClearCMPST3210ET3210〔LUType，MSID，LAI，Classmark1，〕位置更新过程25整理课件切换过程切换分为小区内切换〔IntraCellInternalHandover〕:切换原因(按优先级排序)Cause15&16干扰切换(HighlevelinterferenceonULorDL).Cause10&11:同心圆内圆电平过低而向外园切换〔Toolowlevel,innerzone(innertoouterzoneHO,concentriccell)(UL&DL)〕Cause13:同心圆外圆电平较高时向内圆切换〔ToohighlevelontheULandDL,outerzone(outertoinnerzoneHO,concentriccell)〕BSC内部小区间切换〔IntercellInternalHandover〕切换原因(按优先级排序)Cause7:微小区BadSACCH切换〔SeveralconsecutiveBadSACCHframesreceived(rescuemicrocellHO)〕Cause17&18:微小区高门限切换〔Toolowlevelinamicrocellcomparedtoahighthreshold(UL&DL)〕Cause2&4:质量切换〔TooLowQuality(UL&DL)〕Cause3&5:电平切换〔TooLowLevel(UL&DL)〕Cause6:太长距离且换〔ToolongMS-BSdistance〕Cause22:扩站小区外小区太短距离切换〔TooshortMS-BSdistance〕Cause20:强制直接重试〔ForcedDirectRetry〕Cause25:GPRS重定向〔GPRSRedirection〕26整理课件Cause21:PreferredBand切换〔Highlevelinneighborcellinthepreferredband〕Cause14:宏小区到微小区切换〔HighlevelinaneighbormicrocellformacrocelltomicrocellHO.〕Cause12:PBGT切换〔PowerBudget("BetterCellHO")〕Cause23:话务切换〔TrafficHO〕Cause24:综合捕捉切换〔GeneralCaptureHO〕同步切换IntraCell切换局部InternalInterCell切换异步切换切换过程27整理课件MSBTSBSCMSCMeasurementRepMeasurementResIntracell切换PhysContextReqOCOCPhysContextConfOC:OldChannelNC:NewChannelNCNCChannelActivationAckChannelActivationAssignmentCommandAssignmentCommandOCSABMEstablishIndicationUAOCNCNCNCAssignmentCompleteNCAssignmentCompleteHandoverPerformedRFChannelRelOCRFChannelRelAck.OCST9108ET9108ST9103ET9103ST3107ET3107ST_RCR_ACKET_RCR_ACK原信道上的TA、MS/BS_TxPwr被沿用到了新的信道上IntraCellHO总是用Assignment的过程来完成〔HOCause，CellID，ChnType〕IntraCell切换过程28整理课件IntraCell切换过程——异常情况TCH拥塞IntraCell切换将不会发生T9108超时:BTS对physicalcontextrequest没有响应之后的ChannelActivation消息中将不带TA和及BTS的发射功率信息T9103超时:ChannelActivation没有回应IntraCell切换过程将终止A接口上不会有任何消息传送BSC向BTS发RFChannelRelease消息，释放新信道BSC收到ChannelActivationNegativeAcknowledge消息IntraCell切换过程将终止ChannelActivationNegativeAcknowledge有以下几种原因:ChannelAlreadyActivated(CAA):BSC向和BTS发信道释放消息RadioResourceNotAvailable(RRNA)-Protocolerror(PE):BSC内部释放Requestedtranscodingratenotsupported(RTRNS):BSC内部释放Encryptionalgorithmnotimplemented(EANI):BSC内部释放O&MIntervention(OI):BSC内部释放A接口上不会有任何消息传送29整理课件IntraCell切换过程——异常情况在原来的信道上〔如SDCCH信道〕收到AssignmentFailure消息IntraCell切换过程将终止A接口上不会有任何消息传送BSC向BTS发RFChannelRelease消息，释放新信道AssignmentCommand的内容有误，发AssignmentFailure消息到BSCIntraCell切换过程将终止A接口上不会有任何消息传送BSC向BTS发RFChannelRelease消息，释放新信道T3107超时BSC在A接口发ClearRequest“RadioInterfaceMessageFailure〞BSC向BTS发RFChannelRelease消息，释放新老信道形成切换掉话其它异常中断消息ErrorReportConnectionFailureIndicationReleaseIndicationErrorIndication30整理课件MSBTSservingBSCMSCBTStargetMeasReportMeasResultHOAlarm&CandidateCellPhysContextReqPhysContextConfChannelActivationChannelActAck.HOCommandHOCommandHOAccessHODetectionSABMEstablishIndUAHandoverCompleteHandoverCompleteHandoverPerformedRFChannelReleaseRFChannelRel.Ack.ST9108ET9108ST9103ET9103ST3103ST3103ST3106ET3106ST_RCR_ACKET_RCR_ACKST200ET200原信道上的TA、被沿用到了新的信道上，而MS/BS_TxPwr将用最大功率在新的信道上发射〔AB，DCH〕〔Cell，MA，MAIO，HSN，TS，TA〕〔TA被采用〕InternalInterCell切换过程——同步切换31整理课件MSBTSservingBSCMSCBTStargetHOAlarm&CandidateCellChannelActivationChannelActAck.HOCommandHOCommandHOAccessHODetectionSABMEstablishIndUAHandoverCompleteHandoverCompleteHandoverPerformedRFChannelReleaseRFChannelRel.Ack.ST9103ET9103ST3103ST3103ST3105ET3105PhysicalInfoST3124ET3124ST200ET200ST_RCR_ACKET_RCR_ACKPhysContextReqPhysContextConfST9108ET9108MeasReportMeasResult没有PhysicalContReq过程，原信道上的TA不能被沿用到新的信道上测量TA〔TA〕〔TA被采用〕在RF信道释放前，有PhysicalContextReq过程InternalInterCell切换过程——异步切换32整理课件InternalInterCell切换过程——异常情况TCH拥塞InternalInterCell切换将不会发生T9108超时〔同步切换〕同IntraCell情况T9103超时同IntraCell情况BSC收到ChannelActivationNegativeAcknowledge消息同IntraCell情况33整理课件InternalInterCell切换过程——异常情况在原来的信道上〔如SDCCH信道〕收到HOFailure消息InternalInterCell切换过程将终止A接口上不会有任何消息传送BSC向BTS发RFChannelRelease消息，释放新信道HOCommand的内容有误，发HOFailure消息到BSCInternalInterCell切换过程将终止A接口上不会有任何消息传送BSC向BTS发RFChannelRelease消息，释放新信道T3103超时BSC在A接口发ClearRequest“RadioInterfaceMessageFailure〞BSC向BTS发RFChannelRelease消息，释放新老信道形成切换掉话其它异常中断消息ErrorReportConnectionFailureIndicationReleaseIndicationErrorIndication34整理课件MSBTSservingBSCservingMSCBTStargetMeasReportMeasResultHOAlarm&CandidateCellChannelActivationChannelActAck.HOCommandHOCommandHOAccessHO