Gsm呼叫流程(基本)

GSM呼叫流程目的和內(nèi)容目的介紹GSM正常的呼叫流程（空中接口、A-bis接口和A接口）內(nèi)容GSM網(wǎng)絡(luò)協(xié)議介紹無線鏈路建立流程（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）切換流程（HandoverProcedure）呼叫釋放流程（CallReleaseProcedure）信道釋放流程（ChannelReleaseProcedure）GSM協(xié)議層數(shù)無線網(wǎng)絡(luò)優(yōu)化主要關(guān)心第三層的信令無線網(wǎng)絡(luò)優(yōu)化主要關(guān)心DTAP、RSL的信令無線網(wǎng)絡(luò)優(yōu)化主要關(guān)心DTAP、BSSMAP和部分SCCP的信令DTAPRSLOMLGSM網(wǎng)絡(luò)協(xié)議GSM網(wǎng)絡(luò)協(xié)議信令解碼介紹信令流程的主要階段信令流程的主要階段信令信道(SDCCH)建立階段鑒權(quán),身份識別,加密階段(OPTION)業(yè)務(wù)信道建立階段振鈴,通話階段釋放階段切換(OPTION)Layer3介紹RR:無線資源管理（RadioResourceManagement）由MS、BTS和BSC控制功能舉例Paging管理（PagingManagement）加密管理（CipheredModeManagement）頻點分配（FrequencyRedefinition）信道分配（DedicatedChannelAssignment）切換（HandoverManagement）測量和功率控制（MeasuresandPowerControl）MM:移動性管理（MobilityManagement）由MS和MSC/VLR控制功能舉例鑒權(quán)和身份識別（Authentication/IdentificationProcedures）位置更新（LocationUpdating）IMSIAttach/DetachGSM網(wǎng)絡(luò)協(xié)議CC:呼叫控制（CallControl）由MS和MSC控制功能舉例呼叫處理和路由（Callprocessingandrouting）雙音多頻（DTMFFacilities）短消息服務(wù)（ShortMessageService）附加服務(wù)（SupplementaryService）GSM網(wǎng)絡(luò)協(xié)議定義手機與網(wǎng)絡(luò)間建立一個無線鏈路，用于信令傳送包括以下四個步驟Paging過程（PagingProcedure）（僅用于被叫流程中）隨機接入過程（RandomAccessProcedure）立即分配過程（ImmediateAssignmentProcedure）SCCP聯(lián)接建立過程（SCCPConnectionEstablishmentProcedure）當手機需要與網(wǎng)絡(luò)發(fā)生聯(lián)系時，必須要先建立無線鏈路和A接口的信令連接無線鏈路建立流程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）空中接口Abis接口A接口（RndNbr隨機序列碼，TDMAFrameNbr，Chan，TA）（AGCH）同時對兩個MS分配SDCCH（SDCCH）無線鏈路建立流程MSBTSBSCMSCAuthenticationReqCipheringModeCmdAuthenticationReqAuthenticationReqAuthenticationRespAuthenticationRespAuthenticationRespEncryptionCommandCipheringModeCmdCipheringModeCmpCipheringModeCmpCipheringModeCmpTMSIReallocCmdTMSIReallocCmdTMSIReallocCmdTMSIReallocCmpTMSIReallocCmpTMSIReallocCmpAuthenticationCipheringTMSIReallocST3260ET3260*AuthenticationReject*IdentificationIdentificationRequestST3270ET3270IdentificationRequestIdentificationRequestIdentificationResponseIdentificationRespIdentificationResponseST3250ET3250（RAND）（SRES）RAND與Ki經(jīng)過A3算法得到SRES；經(jīng)過A8算法得到Kc比較SRES（IMSI）選擇加密算法（PermittedAlg，Kc）準備解密接收（Alg，Kc）（Alg（A5算法））開始加密發(fā)射和解密接收如正確解密接收，則下條消息加密發(fā)射已加密的消息（TMSI）VLR從HLR處得到RAND/SRES/Kc鑒權(quán)、身份識別、加密、TMSI重新分配過程定義分配TCH的過程特殊情況排隊（Queuing）直接重試（DirectedRetry）TCH分配過程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時，如需傳送信令，則通過StealingFlag將TCH轉(zhuǎn)換成FACCH一般情況下，在RF信道釋放前都有PhysicalContextReq過程TCH分配過程MSBTSBSCMSCSABM(FACCH)ChannelActivationHOCMDAssignmentRequestPhysicalConReqChan.Act.Ack.HODetectionUAPhys.InfoAssignmentCmpST11ST3103QueuingIndicationET11Atthistime,aTCHbecomefreeTCH擁塞和排隊AssignmentRequestST11QueuingIndicationET11AHandoveralarmisraised.AtargetBTSisselectedHOCMDHOAccessST9103ET9103TTSTTEstablishIndicationTTHOCMPTHOCMPST3124ET3124ET3103直接重試如果QueuingInd=True或Queuing_Anyway=True。（當Queuing_Anyway時T11_Forced取代T11TCH分配過程——排隊和直接重試主叫過程MSBTSBSCMSCRRConnectionEstablishmentRRConnectionEstablishmentRRConnectionEstablishmentAuthenticationProcedureCipheringProcedureAuthenticationProcedureAuthenticationProcedureCipheringProcedureCipheringProcedureTMSIReallocProcedureTMSIReallocProcedureTMSIReallocProcedureCallProceedingSETUPSETUPSETUPCallProceedingCallProceedingAssignmentProcedureAssignmentProcedureAssignmentProcedure（calledpartynbr）ESTIN(CM_Serv_Req)CM_Serv_Req(CMServiceType)SDCCHAlertingAlertingAlertingConnectConnectConnectConnectAck.ConnectAck.ConnectAck.Speech先建立TCH，再接通B側(cè)信道。Alerting在FACCH上發(fā)送TCHCMSERVICEACCEPTCMSERVICEACCEPTCMSERVICEACCEPTCLASSMARKUPDAECLASSMARKCHANGECLASSMARKUPDAEMSBTSBSCMSCCallConfirmedESTIN(PagingResp)RRConnectionEstablishmentRRConnectionEstablishmentRRConnectionEstablishmentAuthenticationProcedureAuthenticationProcedureAuthenticationProcedureCipheringProcedureCipheringProcedureCipheringProcedureTMSIReallocProcedureTMSIReallocProcedureTMSIReallocProcedureSETUPSETUPSETUPCallConfirmedCallConfirmedAssignmentProcedureAssignmentProcedureAssignmentProcedureAlertingAlertingAlertingConnectConnectConnectConnectAck.ConnectAck.ConnectAck.Speech被叫過程只有主叫號碼，主叫過程只有被叫號碼PagingResponsePagingPagingCommandPagingRequestST3113ET3113PagingGroup的個數(shù)（N）：由BS_AG_BLKS_RES和BS_PA_MFRMS決定;MS的PagingGroup=(IMSImod1000)modN;MS只監(jiān)聽自己對應(yīng)的PagingGroup的PagingReq消息（MSID（TMSI/IMSI），CellID（LAC/LAC+CI））（MSID（TMSI/IMSI），PagingGroup）（MSID（TMSI/IMSI））（最多可同時發(fā)4個TMSI）（MobileID，Classmark2，Priority，）（callingpartynbr）被叫過程MSBTSBSCMSCClearCMDESTIN(LocUpReq)RRConnectionEstablishmentRRConnectionEstablishmentRRConnectionEstablishmentAuthenticationProcedureAuthenticationProcedureAuthenticationProcedureCipheringProcedureCipheringProcedureCipheringProcedureTMSIReallocProcedureTMSIReallocProcedureTMSIReallocProcedureLocUpAcceptChannelReleaseDeactivateSACCHDISCReleaseIndicationUARFChReleaseLocUpReqLocUpAcceptLocUpAcceptChannelReleaseRFChReleaseAckClearCMPST3210ET3210（LUType，MSID，LAI，Classmark1，）位置更新過程MSBTSservingBSCMSCBTStargetHOAlarm&CandidateCellChannelActivationChannelActAck.HOCommandHOCommandHOAccessHODetectionSABMEstablishIndUAHandoverCompleteHandoverCompleteHandoverPerformedRFChannelReleaseRFChannelRel.Ack.ST9103ET9103ST3103ST3103ST3105ET3105PhysicalInfoST3124ET3124ST200ET200ST_RCR_ACKET_RCR_ACKPhysContextReqPhysContextConfST9108ET9108MeasReportMeasResult沒有PhysicalContReq過程，原信道上的TA不能被沿用到新的信道上測量TA（TA）（TA被采用）在RF信道釋放前，有PhysicalContextReq過程InternalInterCell切換過程——異步切換ClearCommand如果帶有HO成功則表示切換成功ET3124ST3124ST200ET200ExternalInterCell切換過程——異步切換MSBTSservingBSCservingMSCBTStargetMeasReportMeasResultHOAlarm&CandidateCellChannelActivationChannelActAck.HOCommandHOCommandHOAccessHODetectionSABMEstablishIndUAHandoverCompleteHandoverCompleteHOCompleteRFChannelReleaseRFCh.Rel.Ack.BSCtargetHORequired要求切出HORequest要求切入HORequestAck.HOCommandPhysInformation（SCCPConRequired）（SCCPConConf）.ClearCompleteSCCPReleasedSCCPRel.Cmp.STrr2ETrr2ST_HO_REQ_LostST9103ST9103ST9113ST3103ET3103ST3106ET3106ST8ET8ET9113ET_HO_REQ_LostMSBTSBSCMSCDisconnectDisconnectDisconnectReleaseReleaseReleaseReleaseCompleteReleaseCompleteReleaseComplete手機觸發(fā)的呼叫釋放DisconnectDisconnectDisconnectReleaseReleaseReleaseReleaseCompleteReleaseCompleteReleaseComplete網(wǎng)絡(luò)觸發(fā)的呼叫釋放呼叫釋放過程信道釋放時空中接口和A接口的釋放過程是同時、獨立進行的空中接口的信道釋放過程BSC發(fā)ChannelRelease消息給手機無線鏈路