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1、2008-11-271软交换技术交流软交换技术交流- VOIP - VOIP 和和 BICCBICC协议协议2008-11-272VOIP概念 VOIP-Voice Over Internet Protocol 定义了将语音通过IP网进行传送的方法。 软交换VOIP化是将CS域的语音电话打包后通过IP 骨干网传送。 同在IP 骨干网传送，实现PS域和CS域承载网的融合。 提高设备的利用率，减少营运成本。 有利于新业务的开发和使用。2008-11-273VoIP 网络模型2008-11-274软交换核心网IP化 MobileSoftswitch MobileSoftswitch MobileSo
2、ftswitch MobileSoftswitchTDMISUPBICCIP 专有电路 -共用IP承载网2008-11-275语音IP化网络控制平面信令协议栈Nc Nb A MTP2 MTP3 SCCP BSSAP PHY MTP2 MTP3 ISUP PHY SS7 Network HLR,SGSN Mc PSTN BSS MSC Server IP SCTP ISUP LL M3UA C - MGW TSC Server C - MGW SGW STP Mc B S S A P SCTP M3UA IP LL TCAP MAP B S S A P + R A N A P SCCP SS7
3、Network HLR, SGSN TCAP MAP B S S A P + SCTP M3UA IP SCCP PHY BICC IP SCTP M3UA LL IPBCP IPBCP TCAP MAP B S S A P + MTP2 MTP3 SCCP PHY GCP IP SCTP M3UA LL IPBCP SIGTRAN SIGTRAN SGW STP Nc Nb A MTP2 MTP3 SCCP BSSAP PHY MTP2 MTP3 SCCP BSSAP PHY MTP2 MTP3 ISUP PHY MTP2 MTP3 ISUP PHY SS7 Network HLR,SGSN
4、 Mc PSTN PSTN BSS BSS MSC Server IP SCTP ISUP LL M3UA IP SCTP ISUP LL M3UA C - MGW M - MGw TSC Server C - MGW M - MGw SGW STP Mc B S S A P SCTP M3UA IP LL TCAP MAP B S S A P + R A N A P SCCP B S S A P SCTP M3UA IP LL TCAP MAP B S S A P + R A N A P SCCP SS7 Network HLR, SGSN TCAP MAP B S S A P + SCTP
5、 M3UA IP SCCP PHY TCAP MAP B S S A P + SCTP M3UA IP SCCP PHY BICC IP SCTP M3UA LL IPBCP BICC IP SCTP M3UA LL BICC IP SCTP M3UA LL IPBCP IPBCP TCAP MAP B S S A P + MTP2 MTP3 SCCP PHY TCAP MAP B S S A P + MTP2 MTP3 SCCP PHY GCP IP SCTP M3UA LL IPBCP GCP IP SCTP M3UA LL H.248 IP SCTP M3UA LL IPBCP SIGT
6、RAN SIGTRAN SIGTRAN SIGTRAN SGW STP 2008-11-276RNCBSCMGWMGWMGWMGW A Inter TDMNbUP over RTP over IPUser-planeTransportBearerControl BSSAPQ.IPBCPCore NetworkTransport NetworkPSTN/ISDNISUPTDMSCCPMTP3MTP2MTP1BSSAPM3UASCTP IPLLBICC/GCPQ.IPBCPNbUPUDP IPL1PCM/AMRRTPTDMPCM L1MTP3MTP2MTP1ISUP语音IP化网络用户平面协议栈Nb
7、TDMPCM L12008-11-277新增协议规范 BICC TS 23.205 Bearer Independent CS Core Network. Q.1902.x (x=1,2.6) for BICC protocol CS2 IPBCP Q.1990:BICC bearer control tunneling protocolQ.1970:BICC bearer control protocolSDP RFC 4566 :Session Description Protocol Nb 接口接口TS 29.414 Core Network Nb data Transport and
8、Transport Signaling.TS 29.415 Core Network Nb Interface user Plane protocols.RFC RTP 3550:Transport Protocol for Real-Time Applications.UDP RFC 768:User Datagram Protocol.IP RFC 791(v4) 2460(v6):Internet Protocol2008-11-278 BICC 基本运用Control LayerConnectivity LayerMGWMGWMGWMGWControlServerTo AccessNe
9、twork/sControlServerControlServerbearer/connectivity networkBICCBICCAccessSignalingAccessSignaling在VOIP网络中，MSCServer之间（NC接口）使用BICC协议2008-11-279BICC消息中的控制信息 Action Indicator (connect forward) BNC Identifier BIWF Address Codec List Single Codec BNC Characteristics (IP/RTP) Bearer Control Information B
10、earer Control Tunneling （Tunnelling to be used) 2008-11-2710IPBCP 协议模型ServerMGWBICCGCPGCPMGWQ.1970Q.1970ServerQ.1990Q.1990Tunnelling PDUgenerating & receivingEntities IP bearers with Nb framing MGW之间通过IPBCP和Nb-UP初始化消息建立用户面的连接。 IPBCP 是通过H.248 （MC接口）和 BICC协议(NC接口)中传送2008-11-2711Bearer Control Informat
11、ion (BCI)IPBCP SDPBCTP Indicator FieldQ.1970Q.1990Bearer Control InformationBCI - 承载控制信息，在BICC协议中APM消息中传送2008-11-2712BICC消息中BCI 举例BCTP Version Indicator0: Version 1BCTP Version Error Indicator (BVEI)0: No indicationTunnelled Protocol Indicator32: IPBCPTunnelled Protocol Error Indicator (TPEI)0: No i
12、ndicationBCTP PDU:v=0 o=- 0 0 IN IP4 10.40.63.10 s=- c=IN IP4 10.40.63.10 t=0 0 a=ipbcp:1 Accepted m=audio 33768 RTP/AVP 96 a=ptime:20 a=rtpmap:96 VND.3GPP.IUFP/16000 o=- 0 0 IN IP4 10.40.63.10和IPBCP对内容无要求Address type = IPV6 or IPV4address 发送端的IP地址Origin （o） (发送端描述）Network type = IN (for internet)SD
13、P 版本号Session name (s)本次会话的的描述，IPBCP对内容无要求2008-11-2713BCTP Version Indicator0: Version 1BCTP Version Error Indicator (BVEI)0: No indicationTunnelled Protocol Indicator32: IPBCPTunnelled Protocol Error Indicator (TPEI)0: No indicationBCTP PDU:v=0 o=- 0 0 IN IP4 10.40.63.10 s=- c=IN IP4 10.40.63.10 t=0
14、 0 a=ipbcp:1 Accepted m=audio 33768 RTP/AVP 96 a=ptime:20 a=rtpmap:96 VND.3GPP.IUFP/16000 t= 该内容由发送方根据SDP规则填写，数值(0,0)允许使用，但IPBCP对该内容没有要求，在接受方被忽略 c=IN IP4 10.40.63.10 Network type = IN (for internet)Address type = IPV6 or IPV4Connection address 要求连接的IP地址Connection Data （c）（连接要求）BICC消息中BCI 举例2008-11-2
15、714BCTP Version Indicator0: Version 1BCTP Version Error Indicator (BVEI)0: No indicationTunnelled Protocol Indicator32: IPBCPTunnelled Protocol Error Indicator (TPEI)0: No indicationBCTP PDU:v=0 o=- 0 0 IN IP4 10.40.63.10 s=- c=IN IP4 10.40.63.10 t=0 0 a=ipbcp:1 Accepted m=audio 33768 RTP/AVP 96 a=p
16、time:20 a=rtpmap:96 VND.3GPP.IUFP/16000 m=audio 33768 RTP/AVP 96Media 媒体属性Port No -端口号Media announcement (m)transport RTP/AVP over UDP or just UDP (set to RTP/AVP).Format list 定义媒体载荷的类型Pack time（ms） 打包时长BICC消息中BCI 举例2008-11-2715BCTP Version Indicator0: Version 1BCTP Version Error Indicator (BVEI)0:
17、No indicationTunnelled Protocol Indicator32: IPBCPTunnelled Protocol Error Indicator (TPEI)0: No indicationBCTP PDU:v=0 o=- 0 0 IN IP4 10.40.63.10 s=- c=IN IP4 10.40.63.10 t=0 0 a=ipbcp:1 Accepted m=audio 33768 RTP/AVP 96 a=ptime:20 a=rtpmap:96 VND.3GPP.IUFP/16000 a=rtpmap:96 VND.3GPP.IUFP/16000 Med
18、ia attributes (a)encoding name / clocking rates 对媒体流的编码方式和抽样编码速率payload type 媒体载荷的类型BICC消息中BCI 举例2008-11-2716VOIP化的软硬件要求 软交换节点 MSS R4版本 MSC Server 软件工作在 R12.1 版本.硬件配有GARP板，支持SIGTRAN。 MGW 硬件需为GMP V2.1 或GMP V3.0需安装有ET-MFG板子软件版本 R4.2.1.0 以上2008-11-2717VOIP相关的软件功能 MGW （LKF）IP TransportSS7 Signaling Over
19、 IPCompressed Speech on NbMBACTandem Free Operation (开启TFO 功能需要） MSC Server （Parameter）MGS=2 支持IP 承载 BICCF=1 支持BICC功能OoBTCAVAIL-1 和OoBTCACT-1 -支持编解码的协商TFOAVAIL-1 和TFOACT-1 支持TFO和TFO/TrFO interworking BSC (Parameter和Property ）TFO-1 和TFOSTATUS-1 -支持TFO功能2008-11-2718VOIP化局数据改变 MSC Server开通到对端局的SIGTRAN信
20、令。定义设备类型为BID的BICC路由。修改路由参数 FBBS=1 （承载建立方向为前向） OoBTC=2 （Speech 和3.1KHz Audio OoBTC 允许）ST（设备选择类型） =6 从最低的空闲CIC选。 =7 从最高的空闲CIC选。 =1 基于CIC的随机选择（需装载MDE3990软件包）2008-11-2719MSC Server上 Nc 接口配置主要命令1.开BICC接口功能设置 参数BICCF=1.（命令DBTSC）2.定义到对端软交换局的SCTP关联IHADI:SAID=said ,EPID=epid,RIP=(IP1)&(IP2) ,MODE=PEER;3. 定义到
21、对端软交换局的M3UA路由M3RSI:DEST=(SPC),SAID= said,PRIO=1;M3RAI:DEST=(SPC),SAID= said; 4.定义BICC路由 EXROI:R=biccro&biccri,DETY=BID,SPN=(SPC),FNC=3;EXRBC:R=biccro,RGSPAR=MGG-ALLMG;EXRBC:R=biccro，RGPAR=FBBS-1;EXRBC:R=biccro，RGPAR=OOBTC-2;5.EXDRI &EXDAI&BLODE 来定义BID设备6.ANRSI 来定义BICC RC7.将新的RC定义进B号码分析表 B表分析得到RC得到路由
22、以IP方式建立话务2008-11-2720MGW 中IP端口（NB接口）的配置 MGW配置千兆以太网口 (MO GigaBitEthernet）配置IP 接口 （MO IpInterface）配置IP HOST （MO UdpHostMainMsb ）IP 地址配置 UDP接入HOST （MO IpAccessUdpHostMsb ）端口号。2008-11-2721Nc 接口基本呼叫流程-前向，无编解码协商 无编解码协商 BICC_IAM 中没有Codec List（TRFO功能未开放），承载将缺省建立在G.711(PCM) 编码方式上。MSC Server BMSC Server AAPM（
23、Action = Connect forward, no notification）ACMIAM（Action = Connect forward）,（BNC characteristics=IP/RTP）ANMAPM（Tunnel data=IPBCP Req.msg）APM（Tunnel data=IPBCP Accept msg.）2008-11-2722Nc 接口基本呼叫流程-前向,带编解码协商MSC Server AMSC Server BIAM (Action=connect forward) ,(BNC characteristic=IP/RTP), (Codec list)AP
24、M (Action=connect forward) ,(selected codec), (Available code list) APM (Tunnel Data=IPBCP Req Msg)APM (Tunnel data=IPBCP Ack Msg)COTACMANM2008-11-2723 IP 承载建立消息流程-前向IAM MSCServer-aMGw-aMGw-b MSCServer-bAPMAcc.(IP-b, UDP port)NOTIFYADDAPM Accept (IP-b, UDP port)Req.(IP-a, UDP port)NOTIFYAcc.(IP-b, U
25、DP port)MODIFYMGw-a provides own IP address and UDP port APM Request (IP-a, UDP port)Req.(IP-a, UDP port)MODIFYMGw-b provides own IP address and UDP port NbUP InitializationADDPrepareBearer,TunOpt2EstablishBearer,TunOpt22008-11-2724 Nb接口实现语音压缩传输PCMPCMPCMPCMEFR/FREFR/FREFR/FREFR/FRAMR, compressed spe
26、echAMR, compressed speechBenefit:Benefit: GSM Speech traffic is transported in compressed form.GSM Speech traffic is transported in compressed form. Significant savings in transmission capacity.Significant savings in transmission capacity. Two additional transcoders are inserted in the core network.
27、Two additional transcoders are inserted in the core network.GCPGCPGCPGCPBICC (OoBTC)BICC (OoBTC)BSSAPBSSAPGSMGSMGSMGSMMGWMGWBSCBSCBSSAPBSSAPBSCBSCMGWMGWMSCMSCServerServerMSCMSCServerServerTranscoderTranscoderTranscoderTranscoderTranscoderTranscoderMSC-SAMR 10-20 kbps bandwidthPCM 64 kbpsPCM 64 kbps2
28、008-11-2725BSCBSCM-MGwM-MGwNb接口实现语音压缩传输Compressed speech on Nb Voice Compression for GSM and transit calls Can be enhanced with TFO to provide end-to-end compressed speech with retained speech quality for GSMBenefit 70-85% improved transport efficiency Integrated solution, no additional network elem
29、ents required An evolution path to improved voice quality for GSM OoBTCOoBTC (Out of Band Transcoder Control)OoBTCAMR from M-MGw to M-MGwAMR 10-20 kbps bandwidthPCM64 kbpsPCM64 kbps= TranscoderMSC-SMSC-SMGw2008-11-2726爱立信核心网络支持的语音编码 The Codecs: Codecs supported in R4:GSM_EFR Enhanced codec type for
30、GSM. Single mode at 12.2 kbps. Nearly compatible to AMR12.2. FR_AMR AMR codec type for GSM. 8 modes at 12.24.75 kbps. At most 4 modes can be included in the active codec set at a time. Exactly one codec mode is actively used at any time. A change of the codec mode is possible every 40ms. HR_AMR Low
31、rate AMR codec type for GSM. 6 modes at 7.954.75 kbps. At most 4 modes can be included in the active codec set at a time. Exactly one codec mode is actively used at any time. A change of the codec mode is possible every 40ms. Identical to FR AMR for the corresponding modes. UMTS_AMR2 AMR codec type
32、for WCDMA, 8 modes at 12.24.75 kbps. All of them can be included in the active codec set at the same time. But it is recommended for OoBTC to include at maximum four. A change of the codec mode is possible every 40ms. UMTS_AMR 3GPP R99 AMR codec type for WCDMA. Replaced by UMTS AMR2 in later release
33、s. Allowed only for single mode R99 UMTS terminals. A change of the codec mode is possible every 20ms and therefore UMTS_AMR is not compatible to FR_AMR and HR_AMR. (G.711 (PCM) G.711 (PCM 64kbps A-law or u-law) is the international standard for encoding telephone audio on a 64 kbps PCM channel. Not
34、e: G.711 is not suported on any radio interface, but only on the fixed part of the networks. 2008-11-2727 , R12.1 , R12.1 , R12.1UMTS_AMR2 (Set 1): 12.2, 7.4, 5.9, 4.75 kbit/s R12.1FR_AMR (Set 1): 12.2, 7,4, 5.9, 4.75 kbit/s R12.1HR_AMR (Set 1): 7.4, 5.9, 4.75 kbit/s R12.1GSM-EFR R12.1OoBTC: Message
35、 FlowBSC1MGw1BSC2MGw2Setup / Call Proceed1IAM (SCL)3Start Codec NegotiationBuild Supported Codec List2Terminate Codec NegotiationSelect Codec, Build Available Codec List5Setup / Call Confirm4APM (SC, ACL)7MSC2Seize TerminationACodec = SC11Establish Bearer12MSC1SCL: Supported Codec ListSC: Supported
36、CodecACL: Available Codec ListPCMR11.0UMTS_AMR2 (Set 7): 12.2 kbit/sR11.0UMTS_AMR (Set 7): 12.2 kbit/sR11.0ACodec: Termination PropertySeize TerminationACodec = CIu(SC)8TCH Assignment9Establish Bearer10Seize TerminationACodec = SC6Seize TerminationACodec = CIu(SC)14APM (connect)13TCH Assignment15Est
37、ablish Bearer162008-11-2728SCL - Supported Codec list，Codec list 中的语音编码被分为两个部分：BICC 消息中的SCL的说明Codec ACodec BCodec CPCMCodec 1Codec 2Codec 3Direct codecs：所列的编解码手机终端、无线网络和媒体网关都支持，媒体传送不需要编解码转换器。Indirect codecs：所列的编解码媒体网关支持，但是可能不被手机终端、无线网络都支持，选用这些编解码，媒体网关需要占用编解码转换器资源。PCM在规范 中总是作为编解码的最后选择，所以它的位置在SCL中做为两个
38、编解码表的分界。2008-11-2729 UE/MS手机终端在GSM and WCDMA 网络中通过DTAP Setup / Call Confirm消息将自身支持的编解码列表上传到MSC中。 手机终端上传的编解码列表需要经过TSA（ TELECOMMUNICATION SERVICE ANALYSIS ）中的 PSCVL参数定义的编解码支持列表的检查和滤除(TSA 解释见下页)。 由手机上传到MSC的编解码并符合通过BSC/RNC传送到媒体网关条件的，将被放置在SCL中的“direct codecs”表中。BICC 消息中的SCL的说明2008-11-2730mgtep:tsc=11;MT
39、TELECOMMUNICATION SERVICE ANALYSIS DATAGSM DATATSC 11TEC BEG URATE ITC TRITHYCRT PSCVLFR-FR FRV1 FRV2 FRV3 DHR-DRSC FRV1 FRV2 FRV3 HRV1 HRV3 DFR-DRSC FRV1 FRV2 FRV3 HRV1 HRV3 UMTS DATATSC 11TEC BEG FNUR ITC TRI SERVICETHY A i/f CodecGSM FRGSM Full Rate Version 1GSM HR GSM Half Rate Version 1GSM EFRG
40、SM Full Rate Version 2FR AMRGSM Full Rate Version 3HR AMRGSM Half Rate Version 3 The wanted speech version must be defined in the tele service analysis data for TSC=11Codec Lists的相关定义2008-11-2731BSC codec listList of codecs supported by the BSC MGBSC命令定义RNC codec listList of codecs supported by the
41、RNC MGRIC命令定义DCODECAXE customer parameter “DCODEC” indicates the codec to be used on Nb, if Code selection is performed and no direct codecs are present in the received and the terminating “Supported Codec List”.DBTSC命令来设定Codec Lists的相关定义2008-11-2732MSC内部不同编码的编号Codec IDDescription1PCM (used node int
42、ernal for codec selection)10INMARSAT 11FR_AMR(GC)12GSM_EFR13HR_AMR(GC)14UMTS_AMR2(GC) 15UMTS_AMR2(set 7)16UMTS_AMR(set 7)17UMTS_AMR2(all modes) 18UMTS_AMR(all modes) 2008-11-2733MGw1BSCTFO / TrFO Message FlowSetup / Call Proceed1IAM (SCL)3Start Codec NegotiationBuild Supported Codec List2APM (SC, AC
43、L)4Seize TerminationACodec = SC8Establish Bearer9MSC1TFO Codec List: Includes single codec for TFO request, optional informationEvaluate TFO OptionCompare SC with GSM speech coder versions5Request TFOTFO Codec List6TFO establishmentTFO Codec10TFO Codec: Codec used for TFO establishmentAssignment7APM
44、 (connect)112008-11-2734现网中应CMCC 要求装载的补丁包（MDE） MDE 3930BICC中CIC的随机选择。 MDE 4750 Inter-MSC切换时支持AMR2 Codec。 MDE 3151BICC IAM消息中SCL的配置设置，要求AMR2 放在最高优先级。MDE4750和3151的目的：要求Nb接口只用AMR2 Codec影响：TFO/TRFO功能无法开启，在一定程度上影响语音质 量。2008-11-2735VOIP 网络日常维护要点 将IP设备的监控纳入日常维护。 关注VOIP网络中结点和IP设备的告警，事件和统计报告是日常维护的重点。 故障处理时应时
45、刻将IP BB的状况作为排查的对象。 IP BB的Qos及实际带宽将影响整个网络的运行质量。 基于IP网络的跟踪手段如Ping等将被用作平常网络故障的诊断方法。 以电信级的要求对IP BB的建设质量进行严格规范和验证。2008-11-2736BICCBICC话务链路统计话务链路统计通过对MSC SERVER之间的BID路由进行统计指标名称指标名称指标说明指标说明指标名称指标名称指标说明指标说明BLOL 路由上闭塞的设备数NOSEIZ 成功的呼出占用LASTCONGCNT 出路由的拥塞个数NOVERFLOWO 出路由设备溢出数NANSWERSI 入路由的应答数NRESTRICTO 出路由上的占用
46、限制NANSWERSO 出路由的应答数NTRALACCI 累计的入路由设备占用数NBLOCACC 累计的路由闭塞的设备数NTRALACCO 累计的出路由设备占用数NCALLSI 入路由上侦察到占用的设备数RESTRDEVCNT 出路由的受制设备数NCALLSO 出路由上侦察到占用的设备数THROUGHRTECNT 出路由的through-connections数NDEV 路由上的总设备数TRALI 入路由设备占用数NDSEIZ 双抢占用数TRALO 出路由设备占用数VOIP 网络日常维护要点2008-11-2737追踪、统计追踪、统计MSC SERVER里里VoIP相关的相关的EOS 功能块
47、BIPHT 负责控制对建立,监视和释放BICC的呼叫1662 呼叫释放, 原因是continuity check不成功3739 呼叫释放, 原因是呼叫被拒绝3745 呼叫释放, 原因是没有可用的电路或者信道3748 呼叫释放, 原因是交换设备拥塞3766 呼叫释放, 原因是协议错误VOIP 网络日常维护要点2008-11-2738MSC SERVER检查事件报告检查事件报告 -事件是系统报告一些值得关注的情况 EREPP:ENUM=1012; ! GCP 资源受限 !这个事件产生的原因是资源受限而禁止GCP消息进一步处理. 可能的原因是MGW上的资源不足够或者设备不足够. EREPP:ENUM
48、=1025; ! M3UA SCTP 消息发送失败 !这个事件产生的原因是从SCTP上侦察到M3UA消息不能被发送. 可能的原因是M3UA的路由不通等等. EREPP:ENUM=1030; ! M3UA 拥塞 !这个事件是报告有Association发生拥塞. EREPP:ENUM=1083; ! M3UADR 缓冲拥塞 !这个事件是报告M3UADR功能块的缓存出现拥塞. VOIP 网络日常维护要点2008-11-2739日常检查日常检查MSC SERVER VoIP性能常用指令性能常用指令指令指令描述描述NRGWP媒体网关的状态IHALPSCTP Association的参数和连接状态IHS
49、TPIP端口的状态M3ASPSCTP Association的状态M3RSPM3UA层的路由数据和状态STRSP （STRDP）检查BID设备占用状况VOIP 网络日常维护要点2008-11-2740Mtp3bSpMTP3B信令点Mtp3bSrsMTP3B路由Mtp3bSIMTP3B信令链MgwApplicationMGW的应用Vmgw虚拟媒体网关M3uAssociationM3UA AssociationSctpSCTPGigaBitEthernet千兆以太网IpInterfaceIP 接口IpAccessUdpHostMsbMSB板上话音处理器的接入IpAccessHostGpb话务的Ip
50、 Access Host爱立信MGW VOIP相关主要性能测量VOIP 网络日常维护要点2008-11-2741VMGW中的主要指标 Nb接口初始化化相关 （单位个数） pmNrOfOrigNbInit pmNrOfOrigNbInitFaults pmNrOfTermNbInit pmNrOfTermNbInitSucc IPB设备的统计 （单位个数）pmNrOfIpTermsBusy pmNrOfIpTermsRej pmNrOfIpTermsReq IPBCP相关的统计 （单位个数） pmNrOfRecIpbcpAcceptMsg pmNrOfRecIpbcpConfusedMsg pm