廣域網(wǎng)接入技術(shù)

廣域網(wǎng)接入技術(shù)WAN概述WAN第二層封裝幀中繼概述配置幀中繼配置幀中繼子接口ISDN概述ISDN部件按需撥號(hào)路由選擇概述配置標(biāo)準(zhǔn)DDR1/12/20231廣域網(wǎng)接入技術(shù)WANsconnectremotesites.Connectionrequirementsvarydependingonuserrequirements,cost,andavailability.1/12/20232廣域網(wǎng)接入技術(shù)-WAN連接方式1/12/20233廣域網(wǎng)接入技術(shù)-WAN術(shù)語(yǔ)CPE：用戶室內(nèi)設(shè)備Demarcation:分界點(diǎn)Localloop：本地回路COSwitch：中心局交換機(jī)Tollnetwork：長(zhǎng)途網(wǎng)絡(luò)1/12/20234典型廣域網(wǎng)鏈路層協(xié)議配置合適的數(shù)據(jù)鏈路層封裝類型選擇哪種協(xié)議取決于WAN技術(shù)和通信設(shè)備1/12/20235典型廣域網(wǎng)鏈路層協(xié)議-HDLCUsesaproprietarydatafieldtosupportmultiprotocol

environmentsSupportsonlysingle-protocolenvironmentsHDLC常被用作路由器之間的點(diǎn)到點(diǎn)租用線的封裝方法Cisco提供了一種專用的HDLC版本，同步串行鏈路的默認(rèn)封裝方法。CiscoHDLC幀包含一個(gè)專用的類型字段，起到協(xié)議字段的作用，使得多種網(wǎng)絡(luò)層協(xié)議共享一條串行鏈路。1/12/20236典型廣域網(wǎng)鏈路層協(xié)議-PPPPPP使用網(wǎng)絡(luò)控制協(xié)議（NCP）子層來(lái)封裝多種協(xié)議PPP使用鏈路控制協(xié)議（LCP）子層來(lái)協(xié)商和設(shè)置WAN數(shù)據(jù)鏈路的控制選項(xiàng)1/12/20237典型廣域網(wǎng)鏈路層協(xié)議-PPP分層模型1/12/20238典型廣域網(wǎng)鏈路層協(xié)議-PPPLCP配置選項(xiàng)1/12/20239典型廣域網(wǎng)鏈路層協(xié)議-PPP會(huì)話建立PPP支持兩種身份認(rèn)證協(xié)議：PAP、CHAP1/12/202310典型廣域網(wǎng)鏈路層協(xié)議-PPP認(rèn)證PAP利用雙向握手確認(rèn)呼叫方的合法性當(dāng)PPP鏈路建立階段完成后，呼叫方重復(fù)發(fā)送用戶名/口令對(duì)，直到認(rèn)證被確認(rèn)或未通過(guò)認(rèn)證而拆除鏈路口令以明文的形式在鏈路上傳送1/12/202311典型廣域網(wǎng)鏈路層協(xié)議-PPP認(rèn)證CHAP使用三次握手的方法周期性地驗(yàn)證Hash值(MD5)1/12/202312典型廣域網(wǎng)鏈路層協(xié)議-PPP封裝和認(rèn)證例Router(config-if)#encapsulationpppEnablesPPPencapsulationRouter(config)#hostnamenameAssignsahostnametoyourrouterRouter(config)#usernamenamepasswordpasswordIdentifiestheusernameandpasswordofremoterouterRouter(config-if)#pppauthentication

{chap|chappap|papchap|pap}EnablesPAPand/orCHAPauthentication1/12/202313典型廣域網(wǎng)鏈路層協(xié)議-PPP認(rèn)證例演示1/12/202314幀中繼概述面向連接虛電路幀中繼網(wǎng)絡(luò)本身不對(duì)用戶數(shù)據(jù)進(jìn)行錯(cuò)誤檢測(cè)CSU/DSU接收數(shù)字信號(hào)，并將信號(hào)編碼為交換機(jī)可理解的數(shù)字信號(hào)類型幀中繼運(yùn)行在OSI的下二層OSIReferenceModelFrameRelayPhysicalPresentationSessionTransportNetworkData-LinkApplicationEIA/TIA-232,EIA/TIA-449,V.35,X.21,EIA/TIA-530FrameRelayIP/IPX/AppleTalk,etc.1/12/202316幀中繼術(shù)語(yǔ)本地接入速率虛電路（VC）PVCSVC數(shù)據(jù)鏈路連接符（DLCI）

承諾信息速率（CIR）反向地址解析協(xié)議（反向ARP）

本地管理接口（LMI）前向顯式擁塞通知（FECN）

后向顯式擁塞通知（BECN）幀中繼（NBMA）-問(wèn)題

Problem:只有建立虛電路的兩點(diǎn)間才能通信水平分割問(wèn)題解決水平分割問(wèn)題SplithorizoncancauseproblemsinNBMAenvironments.Subinterfacescanresolvesplithorizonissues.Solution:Asinglephysicalinterfacesimulatesmultiplelogicalinterfaces.UseLMItogetlocallysignificantDLCIfromtheFrameRelayswitch.UseInverseARPtomapthelocalDLCItotheremoterouter’snetworklayeraddress.幀中繼連接的地址映射和LMI信令-地址映射CiscosupportsthreeLMIstandards:Cisco:ansi:ANSI標(biāo)準(zhǔn)

T1.617附錄D定義的LMI類型Q933a:ITU-TQ.933附錄A定義的LMI類型幀中繼連接的地址映射和LMI信令-幀中繼信令路由器收到LMI信息后,將把其VC狀態(tài)更新到下列三種狀態(tài)之一:活動(dòng)狀態(tài)非活動(dòng)狀態(tài)刪除狀態(tài)幀中繼連接的地址映射和LMI信令-鏈路初始化幀中繼連接的地址映射和LMI信令-鏈路初始化配置幀中繼配置靜態(tài)幀中繼映射配置幀中繼子接口-點(diǎn)到點(diǎn)配置幀中繼子接口-多點(diǎn)Displaysline,protocol,DLCI,andLMIinformationRouter#showinterfacess0Serial0isup,lineprotocolisupHardwareisHD64570Internetaddressis/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,outputhangneverLastclearingof"showinterface"countersneverQueueingstrategy:fifoOutputqueue0/40,0drops;inputqueue0/75,0drops<Outputomitted>查看幀中繼連接的狀態(tài)和信息Router#showframe-relaylmi

LMIStatisticsforinterfaceSerial0(FrameRelayDTE)LMITYPE=CISCOInvalidUnnumberedinfo0InvalidProtDisc0InvaliddummyCallRef0InvalidMsgType0InvalidStatusMessage0InvalidLockShift0InvalidInformationID0InvalidReportIELen0InvalidReportRequest0InvalidKeepIELen0NumStatusEnq.Sent113100NumStatusmsgsRcvd113100NumUpdateStatusRcvd0NumStatusTimeouts0查看有關(guān)LMI數(shù)據(jù)流的統(tǒng)計(jì)信息Router#showframe-relaypvc100PVCStatisticsforinterfaceSerial0(FrameRelayDTE)DLCI=100,DLCIUSAGE=LOCAL,PVCSTATUS=ACTIVE,INTERFACE=Serial0inputpkts28outputpkts10inbytes8398outbytes1198droppedpkts0inFECNpkts0inBECNpkts0outFECNpkts0outBECNpkts0inDEpkts0outDEpkts0outbcastpkts10outbcastbytes1198pvccreatetime00:03:46,lasttimepvcstatuschanged00:03:47查看幀中繼連接和關(guān)于數(shù)據(jù)流的統(tǒng)計(jì)信息Displaystheroutemaps,eitherstaticordynamicRouter#showframe-relaymapSerial0(up):ipdlci100(0x64,0x1840),dynamic,broadcast,,statusdefined,active查看幀中繼映射條目ClearsdynamicallycreatedFrameRelaymapsRouter#showframe-relaymapSerial0(up):ipdlci100(0x64,0x1840),dynamic,broadcast,,statusdefined,activeRouter#clearframe-relay-inarpRouter#showframemapRouter#清除動(dòng)態(tài)創(chuàng)建的幀中繼映射1/12/202332什么是ISDN？Voice,data,video,andspecialservicesISDN部件1/12/202334BRI呼叫建立過(guò)程1/12/202335功能是設(shè)備或硬件參考點(diǎn)是分界點(diǎn)或接口ISDNCPE和參考點(diǎn)1/12/202336ISDNBRI接口1/12/202337ISDNPRI接口1/12/202338ISDN交換機(jī)類型和服務(wù)配置文件標(biāo)識(shí)符（SPID）Manyprovidersusemanydifferentswitchtypes.Servicesvarybyregionandcountry.1/12/202339Router(config)#isdnswitch-typeswitch-typeThecommandspecifiesthetypeofISDNswitchwithwhichtheroutercommunicates.Otherconfigurationrequirementsvaryforspecificproviders.Step1:SpecifytheISDNswitchtype.Router(config-if)#isdnswitch-typeswitch-type配置ISDNBRI1/12/202340SetsaBchannelSPIDrequiredbymanyserviceprovidersStep2:(Optional)SettingSPIDsSetsaSPIDforthesecondBchannelRouter(config-if)#isdnspid1spid-number[ldn]Router(config-if)#isdnspid2spid-number[ldn]配置ISDNBRI（續(xù)）1/12/202341配置ISDNPRIRouter(config)#isdnswitch-typeswitch-typeRouter(config)#controllercontrollerslot/portRouter(config-controller)#pri-grouptimeslotsrangeStep1:指定D信道的交換機(jī)類型Step2:配置控制器時(shí)鐘脈沖源、幀類型和線路編碼特征Step3:指定PRI使用T1/E1的哪些信道/時(shí)隙1/12/202342ISDNPRIExamplesRouter(config)#controllerT13/0Router(config-controller)#framingesfRouter(config-controller)#linecodeb8zsRouter(config-controller)#pri-grouptimeslots1-24

Router(config-controller)#interfaceSerial3/0:23Router(config-if)#isdnswitch-typeprimary-5essRouter(config-if)#nocdpenableT1SampleConfigurationRouter(config)#controllerE13/0Router(config-controller)#framingcrc4Router(config-controller)#linecodehdb3Router(config-controller)#pri-grouptimeslots1-31

Router(config-controller)#interfaceSerial3/0:15Router(config-if)#isdnswitch-typeprimary-net5Router(config-if)#nocdpenableE1SampleConfiguration1/12/202343ConnectswhenneededDisconnectswhenfinishedISDNorPSTN按需撥號(hào)路由選擇1/12/202344Periodic（間歇性）connectionsSmallamountsofdata何時(shí)用DDR？1/12/2023451.Routetodestinationisdetermined.2.InterestingpacketsdictateDDRcall.3.Dialerinformationislookedup.4.Trafficistransmitted.5.Callisterminated.DDR工作原理1/12/202346312Definestaticroutes—WhatroutedoIuse?

Specifyinterestingtraffic—Whattrafficenablesthelink?Configurethedialerinformation—WhatnumberdoIcall?配置標(biāo)準(zhǔn)DDR11/12/202347配置靜態(tài)路由1/12/202348dialer-list1protocolippermitdialer-list1protocoliplist101access-list101denytcpanyanyeqftpaccess-list101denytcpanyanyeqtelnetaccess-list101permitipanyanyAnyIPtrafficwillinitiatethelinkwithoutaccesslists.AnyIPtraffic,exceptFTPandTelnet,willinitiatethelinking.Usingaccesslistsgivesfinercontrol.DeniesFTPDeniesTelnet指定感興趣的數(shù)據(jù)流1/12/202349Appliesrulesdefinedbydialer-listtoindividualinterfaceshostnameHome!isdnswitch-typebasic-5ess!usernamecentralpasswordciscointerfaceBRI0ipaddressencapsulationpppdialeridle-timeout180dialermapipnameCentral5552000dialer-group1nofair-queuepppauthenticationchap!routerripnetwork!noipclasslessiprouteiproute!dialer-list1protocolippermitBothValues

MustMatch配置撥號(hào)信息1/12/202350配置撥號(hào)信息（續(xù)）1/12/202351EstablishestheamountoftrafficonthelinkbeforeasecondlinkisenabledRouter(config-if)#dialeridle-timeoutsecondsRouter(config-if)#dialerload-thresholdload

[outbound|inbound|either]Establishestheidletimebeforedisconnect定義負(fù)載均衡（可選）和計(jì)時(shí)器1/12/202352132hostnameHome!isdnswitch-typebasic-5ess!usernamecentralpasswordciscointerfaceBRI0ipaddressencapsulationpppdialeridle-timeout180dialermapipnameCentral5552000dialer-group1nofair-queuepppauthenticationchap!routerripnetwork!noipclasslessiprouteiproutedialer-list1protocolippermit!配置總結(jié)1/12/202353配置ISDNPRI和撥號(hào)配置文件1/12/202354撥號(hào)接口、物理接口和撥號(hào)池間的關(guān)系1/12/202355撥號(hào)配置1/12/202356interfacedialer1ipaddressencapsulationpppdialerremote-nameSmalluserdialerstring5554540dialeridle-timer180dialerpool1dialer-group1pppauthenticationchap!interfacedialer2ipaddressencapsulationpppdialerremote-nameMediumuserdialerstring5551234dialeridle-timer180dialerpool1dialer-group2(cont.)interfacedialer3ipaddressencapsulationpppdialerremote-namePoweruserdialerstring4155554321dialeridle-timer300dialerpool1dialer-group3配置撥號(hào)接口1/12/202357配置物理接口1/12/202358Router#pingortelnetRouter#showdialerRouter#showisdnactiveRouter#showisdnstatusTriggersalinkDisplayscurrentstatusofthelinkDisplayscallstatuswhilecallisinprogressDisplaysthestatusofanISDNconnectionRouter#showiprouteDisplaysallroutes,includingstaticroutes驗(yàn)證DDR和ISDN1/12/202359NASX#showdialerinterfacebri0DialString Successes Failures Lastcalled Laststatus5553872 6 0 19secs Successful0incomingcall(s)havebeenscreened.BRI0:B-Channel1Idletimer(120secs),Fastidletimer(20secs)Waitforcarrier(30secs),Re-enable(15secs)Timeuntildisconnect102secsCurrentcallconnected00:00:19Connectedto5553872(system1)BRI0:B-Channel2Idletimer(120secs),Fastidletimer(20secs)Waitforcarrier(30secs),Re-enable(15secs)DialerstateisidleBRI0-dialertype=ISDNInterfaceboundtoprofileDialer0DialerstateisdatalinklayerupDialreason:ip(s=,d=)驗(yàn)證DDR和ISDN1/12/202360Router#debugdialer[events|packets]DisplaysDDRdebugginginformationaboutthepacketsreceivedonadialerinterfaceClearscurrentlyestablishedconnectionsfromtheinterfaceRouter#debugisdnq921ShowsISDNLayer2messagesRouter(config-if)#shutdownShowsISDNcallsetupandteardownactivityRouter#debugisdnq931診斷DDR和ISDN1/12/202361Router#debugisdnq921

Jan314:52:24.475:ISDNBR0:TX->INFOcsapi=0tei=64ns=5nr=2i=0x08010705040288901801837006803631383835Jan314:52:24.503:ISDNBR0:RX<-RRrsapi=0tei=64nr=6Jan314:52:24.527:ISDNBR0:RX<-INFOcsapi=0tei=64ns=2nr=6i=0x08018702180189Jan314:52:24.535:ISDNBR0:TX->RRrsapi=0tei=64nr=3Jan314:52:24.643:ISDNBR0:RX<-INFOcsapi=0tei=64ns=3nr=6i=0x08018707Jan314:52:24.655:ISDNBR0:TX->RRrsapi=0tei=64nr=4%LINK-3-UPDOWN:InterfaceBRI0:1,changedstatetoupJan314:52:24.683:ISDNBR0:TX->INFOcsapi=0tei=64ns=6nr=4i=0x0801070FJan314:52:24.699:ISDNBR0:RX<-RRrsapi=0tei=64nr=7%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceBRI0:1,changedstatetoup%ISDN-6-CONNECT:InterfaceBRI0:1isnowconnectedto61885goodieJan314:52:34.415:ISDNBR0:RX<-RRpsapi=0tei=64nr=7Jan314:52:34.419:ISDNBR0:TX->RRfsapi=