接口培训资料.ppt
2023年3月27日星期一,接口培训资料,主要内容,A接口位置A接口的分层协议结构A接口消息结构A接口信令流程处理A接口信令的硬件MPA7300多链路协议分析仪,参考规范协议:,ITU-T:Q.700Q.719 Q.750Q.759GSM:08.01,08.02,08.04,08.06,08.08,PSTN,MAP/TCAP+ISUP/TUP-E,To other VLR,ISUP/TUP,DTAP+BSSMAP,MAP/TCAP-C,MAP/TCAP-D,MAP/TCAP-G,A-interface,A接口在GSM中位置,B,F,A_bis,Um,A接口协议组成,基于NO.7信令系统的 MTP and SCCP应用 Base Station Subsystem Application Part(BSSAP)基站子系统管理应用部分-BSS Management Application Part(BSSMAP)Radio Resource(RR)and BSC managementUses SCCP connectionless service(面向连接服务)直接传送应用部分-Direct Transfer Application Part(DTAP)Transfer of Call Control(CM)messagesTransfer of Mobility Management(MM)messagesUses SCCP connection-oriented service(无连接服务),A接口协议分层结构,DTAP,Sig.layer 2,Sig.layer 1,MTP,SCCP,BSSMAP,RR,(CM+MM),BSC,(CM),(MM),(LAPD),BTSM,MTP,MTP,SCCP,SCCP,CM,MM,BSSMAP,TCAP,MAP,I,S,U,P,MSC,A-interface,七号信令与OSI分层结构,F,BIB,BSN,FSN,FIB,LI,SIO,Label,SIF,CK,F,Level 2,Level 3,Level 4,Level 2,F,BIB,BSN,FSN,FIB,LI,SF,CK,F,Level 2,F,BIB,BSN,FSN,FIB,LI,CK,F,Level 2,FISU,LSSU,MSU,FISUFill-in signal unitLSSULink status signal unitMSUMessage signal unitFFlagBSNBackward sequence numberBIBBackward indicator bit,FSNForward sequence numberFIBForward indicator bitLILength indicatorCKCheck sumSFStatus fieldSIOService information octetSIFSignalling information field,Level 2,Level 3,信号单元格式,信号单元格式,MSU:(消息信号单元)是真正携带消息的信号单元,消息包含在SIF和SIO字段中。LSSU:(链路状态信号单元)传送网络链路状态,链路状态由SF字段指示。FISU:(填充信号单元)在网络节点无信息传送时向对方发送空信号,使信令链路保持通信状态。,消息传递部分(MTP),MTP分为三级,功能是提供一个可靠的传递系统,保证两个不同地点对应UP之间传送的信令消息没有差错、丢失和重复。1.第一级:信令数据链路功能 定义了信令数据链路的物理、电气和功能特性以及链路接入方法。信令数据链路应该是透明的,即传送的数据不能有任何改变。2.第二级:信令链路功能 定义了信令消息沿数据链路传送的功能和过程,包括:信号单元的定界和定位 信号单元的差错检测、校正 信令链路的故障检测和恢复 信令链路流量控制,3.第三级:信令网络功能定义了信令网操作和管理的功能和信令过程,由两部分组成:信令消息处理功能包括:消息鉴别 消息分配 消息路由 该功能的作用是实际传递一条信令消息时,引导该消息到达适当的信令链路或用户部分。,消息传递部分(MTP),信令网络管理功能:信令业务管理:将信令业务从一条信令链路或路由转到一条或多条不同的链路或路由,或在信令点拥塞的情况下暂时减少信令业务。信令链路管理:用于控制本端连接的信令链路,包括信令链路的接通、恢复和断开等功能。目的是为建立和保持链路组的正常工作提供手段。信令路由管理:用于在信令点之间可靠地交换关于信令路由是否可用的信息,并及时地闭塞信令路由或解除信令路由的闭塞。,消息传递部分(MTP),信令连接控制部分(SCCP),一、概述 MTP只能实现无连接传输,SCCP的目的是和MTP相结合,提供相当于OSI结构的网络层功能,实现信令消息在任意两个信令点之间透明的直接传输,将SCCP和MTP合称为网络业务部分(NSP)。,信令连接控制部分(SCCP),逻辑信令链路的建立与释放;传送与电路无关的信令消息;具有增强的寻址选路功能,在不同的七号信令网之间实现信令的直接传输;既能提供无连接服务,也能提供面向连接服务。,SCCP的应用特点:,SCCP提供四类协议:,CLASS 0:基本的无连接服务;CLASS 1:消息有序的无连接服务;CLASS 2:基本的面向连接服务;CLASS 3:带有流量控制的面向连接服务。,无连接数据传送,无连接服务:不需预先建立连接,消息由始发节点SCCP经由MTP直接送达终节点SCCP,其传送的消息称单元数据(UDT)。,SCCP1,SCCP2,UDT,SCCP1,SCCP2,SCCP3,MTP1,MTP3,MTP2,UDT,逻辑传输路径,实际传输路径,UDT,无连接数据传送,UDT:UNIT DATA,面向连接数据传送,面向连接服务:需要在发送消息之前,先通过应答的方式在始节点和终节点间建立一条消息传输路径,即信令逻辑连接或虚连接,这种方式适合传送大量的成批数据。因为数据发送前确认终节点能收到数据,同时预先建立连接使后续数据的传输不需要再进行路由选择,缩短传输时延。面向连接服务有两类协议,即2类和3类协议,它们都可以保证消息传送收发顺序一致,可以对长消息分段传送,在接收端重新组装,此外,3类协议还具有流量控制、加速数据传送和消息丢失及错序检测等增强功能。SCCP寻址选路功能:DPC+SSN 和 GT,面向连接数据传送,SCCP消息,1 消息类型 ITU-T建议共定义16种SCCP消息,根据应用范围归为四类:(1)无连接服务消息(UDT、UDTS)(2)连接建立和释放消息(CR、CC、CREF、RLSD、RLC)(3)面向连接数据传送消息(DT1、DT2、AK、ED、EA、RSR、RSC)(4)异常处理消息(ERR、IT),CRConnection requestCCConnection confirmCREFConnection refusedRLSD ReleasedRLCRelease completeDT1Data form 1UDTUnit dataUDTSUnit data serviceERRProtocol data unit error ITInactivity test,SCCP消息,SCCP 消息格式,F,BIB,BSN,FSN,FIB,LI,SIO,Label,SIF,CK,F,Destinationpoint code,Originatingpoint code,SLS,SCCP 用户数据,消息类型,SCCP 消息结构,SCCP消息是封装在MTP的MSU中向外发送的,对于MSU而言,SCCP就是其SIF字段。由以下几部分组成:1、路由选择标记:结构为OPC+DPC+SLS;2、消息类型:识别不同的SCCP消息;3、长度固定的必备部分4、长度可变的必备部分5、任选部分,BSSMAP(BSS Management Application Part),基站子系统管理应用部分 BSSMAP支持在MSC和BSS之间所有要求解释和与呼叫、资源管理有关的信息过程,有些BSSMAP还与无线资源管理消息有关。BSSMAP消息:,Assignment messages(setup of traffic channels)-分配消息Assignment requestAssignment completeAssignment failureHandover messages-切换消息Handover request(to BSC:request for handover to that BSC)Handover required(to MSC:inter BSC/MSC handover required)Handover request ack.(to MSC:acknowledge of handover request)Handover command(to BSC:contains new radio channel/BTS for the MS)Handover complete(to MSC:commanded handover successful)Handover failure(to MSC:commanded handover unsuccessful)Handover performed(to MSC:BSC has performed internal handover)Handover candidate enquiry(to BSC:MSC requests list of MS that could be handedover to another cell)Handover candidate response(to MSC:answer to handover candidate enquiry)Handover required reject(to BSC:required handover unsuccessful)Handover detect(to MSC:commanded handover successful),Release messages-释放消息Clear command(release of traffic channel)Clear completeClear requestSAPI“n”clear command(control of layer 2 SAPI“n”on the radio interface)SAPI“n”clear completeSAPI“n”rejectGeneral messages-一般消息Reset(initialisation of BSS or MSC due to failure)Reset acknowledgeOverload(processor or CCCH overload)Trace invocation(start production of trace recordReset circuit(initialisation of single circuit due to failure)Reset circuit acknowledgeTerrestrial resource messages-陆地资源消息Block(management of circuits/time slots between MSC and BTS)Blocking acknowledgeUnblockUnblocking acknowledge,BSSMAP消息(2),Radio resource messages-无线资源管理消息Resource request(available radio channels in BSS cells)Resource indicationPaging(paging of MS)Cipher mode command(start encryption)Classmark update(change of MS power class)Cipher mode completeQueuing indication(indicates delay in assignment of traffic channel)Complete layer 3 information(contains first message received from MS;sets up SCCP connection),BSSMAP消息(3),F,BIB,BSN,FSN,FIB,LI,SIO,Label,SIF,CK,F,SCCP address FE=BSSAP,Disc.0=BSSMAP,Length indicator,BSSMAP message type,BSSMAP message,BSSMAP消息格式,DTAP(Direct Transfer Application Part),直接传送应用部分 DTAP消息用于在MSC和MS之间传递呼叫控制和移动管理消息,BSS不对其进行解释。DTAP消息:,1.Mobility Management(MM)-移动管理,Registration messages-寄存消息IMSI detach indication(inactive indication of IMSI/TMSI)Location updating accept(control of roaming)Location updating rejectLocation updating request Security messages(control of authentication and TMSI allocation)-安全消息Authentication rejectAuthentication requestAuthentication responseIdentity requestIdentity responseTMSI reallocation commandTMSI reallocation complete,DTAP消息(2),Connection-management messages(control of CM access)-连接管理消息CM service acceptCM service rejectCM service requestCM reestablishment requestMiscellaneous messages-MM status(reports signalling-error conditions),2.Call Control(CC)-呼叫控制,Call establishment messages-呼叫建立消息AlertingCall confirmedCall proceedingConnectConnect acknowledgeEmergency setupProgressSetup,DTAP消息(3),Call information phase messages-呼叫信息阶段消息Modify(used to modify a call from speech to data)Modify completeModify rejectUser information(transfer information between GSM/ISDN users)Call clearing messages-呼叫清除消息DisconnectReleaseRelease completeMiscellaneous messages-Congestion control(flow control for user-information messages)Notify(informs remote user of suspend/resume)Status(reports signalling-error conditions)Status enquiryStart DTMFStop DTMFStop DTMF acknowledgeStart DTMF acknowledgeStart DTMF reject,Short message service(SMS)-短消息业务,DTAP消息(4),MessagesCP-data(transfer of SMS message)CP-ack(acknowledgement of received SMS message)CP-error(error indication)Information elements CP-user data(contains the SMS message)CP-cause(indicates reason for CP error message,Supplementary Services(SS)-补充业务,DTAP消息(4),MessagesHold(used to put an active call on hold when sync.ofresources between MS and network is required)Hold acknowledgeHold rejectRetrieve(retrieve a call from hold)Retrieve acknowledgeRetrieve rejectFacility(request of supplementary services during a call)Register(request of supplementary services outside a call)Information elementsFacility(used for request of supplementary services),DTAP 消息格式,F,BIB,BSN,FSN,FIB,LI,SIO,Label,SIF,CK,F,SCCP address FE=BSSAP,Disc.1=DTAP,Length indicator,BSSMAP message type,BSSMAP message,Fixed Length Info.Element Format,Information Element Identifier,Length of Information Elements,Content of Information Elements,Variable Length Info.Element Format,Information Element Identifier,Content of Information Elements,DLCI,SCCP信令,Location Update,MS,BTS,BSC,MSC,VLR,VLR,HLR,Location Update Request(old LAI,TMSI)MM,Update Location Area(old LAI,new LAI,TMSI),Send Identification,Send Identification Ack(IMSI),Update Location(IMSI,MSRN,VLR no),Cancel Loc(IMSI,VLR no),Cancel Location Ack,Insert Subscriber Data(IMSI,service inf),Insert Subscriber Data Acknowledge,Update Location Area Ack,Forward New TMSI(TMSI),Location Update Accept(new LAI,TMSI)MM,TMSI Reallocation Complete MM,TMSI Ack,Channel Release RR,Clear Command RR,CC,Channel Release Complete,Clear Complete,RLSD,RLC,CR,Authentication Request,Authentication Response,Cipher Mode Command,Cipher Mode Command,Cipher Mode Complete,Cipher Mode Complete,Authenticate(RAND),Authentication Response(SRES),Update Location Ack,Set Cipher Mode,(A),Outgoing Call,BTS,BSC,MSC,VLR,ISDN,Immediate Assign,RR,CM Service Req(IMSI,transact)MM(CR),Process Access Request,Authenticate(RAND),Authentication Request(RAND)MM,Authentication Response(SRES)MM,Authentication Response(SRES),Set ciphering mode(key),Ciphering Mode Command(key)RR,Ciphering Mode Complete RR,Access Request,Ack,SETUP(service,called number)CM,Send info for o/g(service,called number),Complete,call,Call Proceeding,Assign Request RR,Assign Command RR,Assign Complete,IAM,ACM,ANM,Alerting CM,Connect CM,Connect Ack,CC,MS,Channel Request/Required RR,(A),Signalling-incoming call,IAM(MSISDN,service),BTS,BSC,MSC,VLR,HLR,GMSC,ISDN,Send Routing Info(MSISDN),Roaming Number(MSRN),Routing Info(MSRN),Provide Roaming Number(IMSI),IAM(MSRN,service),Send Info Incoming Call(MSRN,service),Page(IMSI,TMSI,LAI),Paging Request(TMSI)RR,Paging Response(TMSI)RR,Page Result,Complete Call(service),Channel Request RR,Immediate Assign RR,SETUP(service)CM,Call Confirm CM,Assign Command RR,Assign Req RR,Assign Complete RR,Alerting CM,ACM,Connect CM,ANM,Connect Ack CM,Complete Call Result,MS,Signalling-inter-MSC handover,MS,BTS,BSC-A,MSC-A,BSC-B,MSC-B,VLR-B,Handover Required(new BTS)RR,Perform handover(new BTS,Ch type),Handover Request(new BTS),Handover Req Ack(Radio Ch),Allocate handover number,Send handover report,(MSRN),(MSRN),Radio Ch Ack(Radio Ch,MSRN),IAM(MSRN),ACM,Handover Command(Radio CH)RR,Handover Complete RR,Clear CommandRR,Clear CompleteRR,Send End Signal,Answer,Measurement Result RR,A interface-Handovers,MSC1,BSC1,BTS,MSC2,BSC2,BTS,BSC1,BTS,BSC2,BTS,BTS,BTS,MSC2,BSC2,Handover required,Handover command,Handover complete,MSC1,BSC1,Handover request,Handover request ack.,Handover detect,MSC2,BSC2,Handover required,Handover command,Handover complete,MSC1,BSC1,Handover request,Handover request ack.,Handover detect,MSC,BSC,Handover performed,BSS侧处理信令的硬件,1、MTP-DTC1、5、9、13、17,即每个HIGHWAY 的第一块DTC。2、SCCP-DTC2、6、7、8、10、14、15、16;一个 SCCP支持256个用户的寻址,需2块DTC支持。3、BSSAP-同SCCP。另外,MSC侧处理BSSAP信令的模块是EBSTCE。,MPA7300多链路协议分析仪,主要特点:每台满配置为16路双向链路;同时跟踪100个呼叫流程;大量的统计功能和硬盘存储空间;可预定义消息触发器和过滤器;用户可灵活定义结果的显示方式和检索方式;具有ODBC功能,可对测试结果进行进一步的统计分析。,MPA7300多链路协议分析仪,菜单项,工具条,状态条,应用窗口,MPA7300的TLINK设置,MPA7300的SLINK设置,MPA7300的测量设置,MPA7300的统计设置,MPA7300的过滤设置,MPA7300的过滤设置,MPA7300的统计显示,