帧中继FrameRelay.ppt
2006,ShenzhenPolytechnic.Allrightsreserved.1帧中继FrameRelay Still waters run deep.流静水深流静水深,人静心深人静心深 Where there is life,there is hope。有生命必有希望。有生命必有希望2006,ShenzhenPolytechnic.Allrightsreserved.2教学目标（教学目标（Objectives ）1.帧中继概念（帧中继概念（FrameRelayConcept）2.帧中继术语（帧中继术语（FrameRelayTerminology）3.帧中继地址映射（帧中继地址映射（FrameRelayAddressMapping）4.LMI操作（操作（LMIOperation）5.帧中继反向帧中继反向ARP（FrameRelayInverseARP）6.配置基本的帧中继配置基本的帧中继（ConfiguringBasicFrameRelay）7.配置配置帧中继子接口（帧中继子接口（ConfiguringFrameRelaySubinterfaces）2006,ShenzhenPolytechnic.Allrightsreserved.3帧中继预览帧中继预览（FrameRelayOverview）帧中继用虚电路为面向连接的服务建立连接帧中继用虚电路为面向连接的服务建立连接VirtualcircuitsmakeconnectionsforConnection-orientedservice帧中继工作在这里帧中继工作在这里FrameRelayworkshere.DCEorFrameRelaySwitchCSU/DSU2006,ShenzhenPolytechnic.Allrightsreserved.4帧中继协议族帧中继协议族（FrameRelayStack）OSIReferenceModelFrameRelayPhysicalPresentationSessionTransportNetworkDataLinkApplicationEIA/TIA-232,EIA/TIA-449,V.35,X.21,EIA/TIA-530FrameRelayIP/IPX/AppleTalk,etc.帧中继工作在帧中继工作在OSI参考模型的参考模型的物理层和数据链路层物理层和数据链路层FrameRelayoperatephysicalanddatalinklayer.2006,ShenzhenPolytechnic.Allrightsreserved.5帧中继术语帧中继术语（FrameRelayTerminology）LocalAccessLoop=T1LocalAccessLoop=64kbpsLocalAccessLoop=64kbpsDLCI:400PVCDLCI:500LMI100=Active400=ActiveDLCI:200DLCI:100PVC2006,ShenzhenPolytechnic.Allrightsreserved.6帧中继术语帧中继术语（FrameRelayTerminology）1.访问速率访问速率（Accessrate）：连接本地环到帧中继的端口速度。）：连接本地环到帧中继的端口速度。Theclockspeed(portspeed)oftheconnection(localloop)totheFrameRelaycloud.2.数据链路连接标识数据链路连接标识（DLCI）：在源和目的设备之间标识逻辑电路的）：在源和目的设备之间标识逻辑电路的一个数值。一个数值。AnumberthatidentifiestheendpointinaFrameRelaynetwork.3.本地管理接口本地管理接口（LMI）；是客户前端设备和帧中继交换机之间的信）；是客户前端设备和帧中继交换机之间的信令标准，负责管理设备之间的连接、维护设备之间的连接状态。令标准，负责管理设备之间的连接、维护设备之间的连接状态。Asignalingstandardbetweenthecustomerpremisesequipment(CPE)deviceandtheFrameRelayswitchthatisresponsibleformanagingtheconnectionandmaintainingstatusbetweenthedevices4.承诺信息速率承诺信息速率（CIR）：）：ISP提供的有保障的速率。提供的有保障的速率。Theguaranteedrate,inbitspersecond,whichtheserviceprovidercommitstoproviding.2006,ShenzhenPolytechnic.Allrightsreserved.7帧中继术语帧中继术语（FrameRelayTerminology）5.前向显示拥塞通知前向显示拥塞通知（FECN）：当网络发生拥塞的时候，向目的设）：当网络发生拥塞的时候，向目的设备发送一个备发送一个FECN数据包，来通知拥塞。数据包，来通知拥塞。AbitsetinaframethatnotifiesaDTEthatcongestionavoidanceproceduresshouldbeinitiatedbythesendingdevice6.后向显示拥塞通知后向显示拥塞通知（BECN）：当网络发生拥塞的时候，向源路由）：当网络发生拥塞的时候，向源路由器发送一个器发送一个BECN数据包，来通知拥塞。同时按数据包，来通知拥塞。同时按25%的比例降低数据的比例降低数据报发送速率。报发送速率。AbitsetinaframethatnotifiesaDTEthatcongestionavoidanceproceduresshouldbeinitiatedbythesendingdevice.IftherouterreceivesanyBECNsduringthecurrenttimeinterval,itdecreasesthetransmitrateby25%.7.允许丢弃指示器允许丢弃指示器（DE）：当路由器检测到拥塞时，帧中继交换机将）：当路由器检测到拥塞时，帧中继交换机将会首先丢弃那些会首先丢弃那些DE位设置为位设置为1的数据包。的数据包。Asetbitthatindicatestheframemaybediscardedinpreferencetootherframesifcongestionoccurs.2006,ShenzhenPolytechnic.Allrightsreserved.8CSU/DSU帧中继地址映射帧中继地址映射（FrameRelayAddressMapping）从从ISP获得本地意义的获得本地意义的DLCI号码号码GetlocallysignificantDLCIsfromprovider把网络地址映射到把网络地址映射到DLCIMapyournetworkaddressestoDLCIsDLCI:500PVC10.1.1.1InverseARPorFrameRelaymapIP(10.1.1.1)FrameRelayDLCI(500)2006,ShenzhenPolytechnic.Allrightsreserved.9LMI类型（类型（LMITYPES）Cisco支持三种类型的支持三种类型的LMI标准标准CiscosupportsthreeLMIstandards:Cisco（默认）（默认）ANSIQ.933*在路由器上配置的在路由器上配置的LMI类型必须和类型必须和SP提供的匹配。提供的匹配。*LMItypeconfiguredontheroutermustmatchthetypeusedbytheserviceprovider.DLCI:400PVCKeepaliveCSU/DSUDLCI:500PVC10.1.1.1xLMI500=Active400=Inactive2006,ShenzhenPolytechnic.Allrightsreserved.10帧中继反向帧中继反向ARP（FrameRelayInverseARP）FrameRelayCloud1DLCI=100DLCI=400172.168.5.5172.168.5.72006,ShenzhenPolytechnic.Allrightsreserved.11帧中继反向帧中继反向ARP（FrameRelayInverseARP）2StatusInquiry2StatusInquiryFrameRelayCloud1DLCI=100DLCI=400172.168.5.5172.168.5.72006,ShenzhenPolytechnic.Allrightsreserved.12帧中继反向帧中继反向ARP（FrameRelayInverseARP）3LocalDLCI100=Active4LocalDLCI400=Active2StatusInquiry2StatusInquiryFrameRelayCloud1DLCI=100DLCI=4003172.168.5.5172.168.5.72006,ShenzhenPolytechnic.Allrightsreserved.13帧中继反向帧中继反向ARP（FrameRelayInverseARP）4Hello,Iam172.168.5.5.3LocalDLCI100=Active4LocalDLCI400=Active2StatusInquiry2StatusInquiryFrameRelayCloud1DLCI=100DLCI=4003172.168.5.5172.168.5.72006,ShenzhenPolytechnic.Allrightsreserved.14帧中继反向帧中继反向ARP（FrameRelayInverseARP）Hello,Iam172.168.5.7.45FrameRelayMap172.168.5.5DLCI400ActiveFrameRelayCloudDLCI=100DLCI=400FrameRelayMap172.168.5.7DLCI100Active5172.168.5.5172.168.5.72006,ShenzhenPolytechnic.Allrightsreserved.15帧中继反向帧中继反向ARP（FrameRelayInverseARP）Hello,Iam172.168.5.7.45FrameRelayMap172.168.5.5DLCI400ActiveFrameRelayCloudDLCI=100DLCI=400FrameRelayMap172.168.5.7DLCI100Active5Hello,Iam172.168.5.5.6172.168.5.5172.168.5.72006,ShenzhenPolytechnic.Allrightsreserved.16帧中继反向帧中继反向ARP（FrameRelayInverseARP）KeepalivesKeepalivesHello,Iam172.168.5.7.45FrameRelayMap172.168.5.5DLCI400ActiveFrameRelayCloudDLCI=100DLCI=400FrameRelayMap172.168.5.7DLCI100Active5Hello,Iam172.168.5.5.677172.168.5.5172.168.5.72006,ShenzhenPolytechnic.Allrightsreserved.17interfaceSerial10/1ipaddress10.16.0.1255.255.255.0encapsulationframe-relaybandwidth64Frame-relaylmi-typeciscointerfaceSerial0/1ipaddress10.16.0.2255.255.255.0encapsulationframe-relaybandwidth64frame-relaylmi-typeciscoHQBranch配置基本的帧中继配置基本的帧中继（ConfiguringBasicFrameRelay）反向反向ARPARP默认被启动默认被启动Inverse ARP is enabled by defaultInverse ARP is enabled by default2006,ShenzhenPolytechnic.Allrightsreserved.18DLCI=110IPaddress=10.16.0.1/24p1r1DLCI=100IPaddress=10.16.0.2/24interface Serial1interface Serial1ip address 10.16.0.1 255.255.255.0ip address 10.16.0.1 255.255.255.0encapsulation frame-relayencapsulation frame-relaybandwidth 64bandwidth 64frame-relay map ip 10.16.0.2 110 broadcastframe-relay map ip 10.16.0.2 110 broadcastHQBranch配置帧中继静态映射配置帧中继静态映射（ConfiguringaStaticFrameRelayMap）2006,ShenzhenPolytechnic.Allrightsreserved.19验证帧中继配置验证帧中继配置（VerifyingFrameRelayOperation）Router#showinterfaces0/0Serial0isup,lineprotocolisupHardwareisHD64570Internetaddressis10.140.1.2/24MTU1500bytes,BW1544Kbit,DLY20000usec,rely255/255,load1/255EncapsulationFRAME-RELAY,loopbacknotset,keepaliveset(10sec)LMIenqsent19,LMIstatrecvd20,LMIupdrecvd0,DTELMIupLMIenqrecvd0,LMIstatsent0,LMIupdsent0LMIDLCI1023LMItypeisCISCOframerelayDTEFRSVCdisabled,LAPFstatedownBroadcastqueue0/64,broadcastssent/dropped8/0,interfacebroadcasts5Lastinput00:00:02,output00:00:02,outputhangneverLastclearingofshowinterfacecountersneverQueueingstrategy:fifoOutputqueue0/40,0drops;inputqueue0/75,0drops2006,ShenzhenPolytechnic.Allrightsreserved.20showframe-relaylmi：命令显示命令显示LMI信息信息showframe-relaylmi：DisplaysLMIinformationRouter#showframe-relaylmiLMIStatisticsforinterfaceSerial0(FrameRelayDTE)LMITYPE=CISCOInvalidUnnumberedinfo0InvalidProtDisc0InvaliddummyCallRef0InvalidMsgType0InvalidStatusMessage0InvalidLockShift0InvalidInformationID0InvalidReportIELen0InvalidReportRequest0InvalidKeepIELen0NumStatusEnq.Sent113100NumStatusmsgsRcvd113100NumUpdateStatusRcvd0NumStatusTimeouts0验证帧中继配置验证帧中继配置验证帧中继配置验证帧中继配置（VerifyingFrameRelayOperationVerifyingFrameRelayOperation）2006,ShenzhenPolytechnic.Allrightsreserved.21showframe-relaypvc100：显示：显示PVC状态信息状态信息showframe-relaypvc100：DisplaysPVCtrafficstatistics验证帧中继配置验证帧中继配置验证帧中继配置验证帧中继配置（VerifyingFrameRelayOperationVerifyingFrameRelayOperation）Router#showframe-relaypvc100PVCStatisticsforinterfaceSerial0(FrameRelayDTE)DLCI=100,DLCIUSAGE=LOCAL,PVCSTATUS=ACTIVE,INTERFACE=Serial0inputpkts28outputpkts10inbytes8398outbytes1198droppedpkts0inFECNpkts0inBECNpkts0outFECNpkts0outBECNpkts0inDEpkts0outDEpkts0outbcastpkts10outbcastbytes1198pvccreatetime00:03:46,lasttimepvcstatuschanged00:03:472006,ShenzhenPolytechnic.Allrightsreserved.22showframe-relaymap：显示帧中继映射信息：显示帧中继映射信息,包括静态或动态包括静态或动态showframe-relaymap:Displaystheroutemaps,eitherstaticordynamicRouter#showframe-relaymapSerial0(up):ip10.140.1.1dlci100(0 x64,0 x1840),dynamic,broadcast,statusdefined,active验证帧中继配置验证帧中继配置验证帧中继配置验证帧中继配置（VerifyingFrameRelayOperationVerifyingFrameRelayOperation）2006,ShenzhenPolytechnic.Allrightsreserved.23问题：广播流量必须被发送到每一条问题：广播流量必须被发送到每一条PVCProblem:BroadcasttrafficmustbereplicatedforeachpvcRoutingUpdateACB231路由更新的可达性问题路由更新的可达性问题（ReachabilityIssueswithRoutingUpdates）BCDA2006,ShenzhenPolytechnic.Allrightsreserved.24解决可达性问题解决可达性问题（ResolvingReachabilityIssues）方案（方案（Solution）:在在NBMA环境下，存在水平分割的问题环境下，存在水平分割的问题SplithorizoncancauseproblemsinNBMAenvironments子接口可以解决水平分割的问题子接口可以解决水平分割的问题Subinterfacescanresolvesplithorizonissues一个单一的物理接口模拟多个逻辑接口一个单一的物理接口模拟多个逻辑接口AsinglephysicalinterfacesimulatesmultiplelogicalinterfacesSubnetASubnetBSubnetCS0PhysicalInterfaceS0.1S0.2S0.3LogicalInterface2006,ShenzhenPolytechnic.Allrightsreserved.25配置子接口（配置子接口（ConfiguringSubinterfaces）点到点（点到点（Point-to-Point）子接口充当专线子接口充当专线Subinterfacesactasleasedline每一个子接口有自己的子网每一个子接口有自己的子网Eachpoint-to-pointsubinterfacerequiresitsownsubnet应用在应用在hubandspoke拓扑中拓扑中Applicabletohubandspoketopologies2006,ShenzhenPolytechnic.Allrightsreserved.26配置子接口（配置子接口（ConfiguringSubinterfaces）多点（多点（Multipoint）向向NBMA网络一样，不能解决水平分割的问题网络一样，不能解决水平分割的问题SubinterfacesactasNBMAnetworksotheydonotresolvethesplithorizonissue使用同一子网，可以节省地址空间使用同一子网，可以节省地址空间Cansaveaddressspacebecauseusessinglesubnet应用在应用在partial-mesh和和full-mesh拓扑中拓扑中Applicabletopartial-meshandfull-meshtopology2006,ShenzhenPolytechnic.Allrightsreserved.27A10.17.0.1s0.2B配置点到点子接口实例配置点到点子接口实例（ConfiguringPoint-to-PointSubinterfacesExample）interfaceSerial0noipaddressencapsulationframe-relay!interfaceSerial0.2point-to-pointipaddress10.17.0.1255.255.255.0bandwidth64frame-relayinterface-dlci110!interfaceSerial0.3point-to-pointipaddress10.18.0.1255.255.255.0bandwidth64frame-relayinterface-dlci120!s0.310.18.0.1C10.17.0.210.18.0.2DLCI=110DLCI=1202006,ShenzhenPolytechnic.Allrightsreserved.28 interfaceSerial2noipaddressencapsulationframe-relay!interfaceSerial2.2multipointmultipointipaddress10.17.0.1255.255.255.0bandwidth64frame-relaymapip10.17.0.2120broadcastframe-relaymapip10.17.0.3130broadcastframe-relaymapip10.17.0.4140broadcasts2.1=10.17.0.2/24s2.2=10.17.0.1/24s2.1=10.17.0.4/24s2.1=10.17.0.3/24RTR1BRTR3RTR4配置多点子接口实例配置多点子接口实例（MultipointSubinterfacesConfigurationExample）DLCI=120DLCI=130DLCI=1402006,ShenzhenPolytechnic.Allrightsreserved.29思考题（思考题（Questions）1.什么是帧中继？什么是帧中继？2.什么是什么是DLCI？它是局部意义还是全局意义？它是局部意义还是全局意义？3.LMI有几种类型？有几种类型？4.FECN和和BECN的区别是什么？的区别是什么？5.如何查看帧中继如何查看帧中继PVC的状态？的状态？6.如何建立一条帧中继的交换记录？如何建立一条帧中继的交换记录？
