HDLC&PPP原理與配置Page2前言廣域網(wǎng)中經(jīng)常會(huì)使用串行鏈路來提供遠(yuǎn)距離的數(shù)據(jù)傳輸，高級(jí)數(shù)據(jù)鏈路控制HDLC（High-LevelDataLinkControl）和點(diǎn)對(duì)點(diǎn)協(xié)議PPP（PointtoPointProtocol）是兩種典型的串口封裝協(xié)議。Page3學(xué)習(xí)目標(biāo)

學(xué)完本課程后，您應(yīng)該能：掌握HDLC和PPP的工作原理掌握HDLC和PPP的基本配置串行鏈路的數(shù)據(jù)傳輸方式Page4主機(jī)ARTAStopDataStartStopDataStart……異步1byte同步DCEDTE基于DCE時(shí)鐘同步FlagDataFlagHDLC協(xié)議應(yīng)用Page5RTARTBHDLCS1/0/0S1/0/0High-levelDataLinkControl，高級(jí)數(shù)據(jù)鏈路控制，簡稱HDLC，是一種面向比特的鏈路層協(xié)議。HDLC幀結(jié)構(gòu)Page6FlagInformationControlAddressFCSFlag11MMP/FMMMUS10SSP/FP/FI0N(S)P/F01234567N(R)HDLC有三種類型的幀：信息幀、監(jiān)控幀、無編號(hào)幀。HDLC基本配置Page7S1/0/0RTARTB[RTA]interfaceSerial1/0/0[RTA-Serial1/0/0]link-protocolhdlc

Warning:Theencapsulationprotocolofthelinkwillbechanged.Continue?[Y/N]:y[RTA-Serial1/0/0]ipaddress10.0.1.130S1/0/010.0.1.1/30HDLC接口地址借用Page8RTARTB10.1.1.2/24Loopback010.1.1.1/32[RTA]interfaceSerial1/0/0[RTA-Serial1/0/0]link-protocolhdlc

Warning:Theencapsulationprotocolofthelinkwillbechanged.Continue?[Y/N]:y[RTA-Serial1/0/0]ipaddressunnumberedinterfaceloopBack0[RTA]iproute-static10.1.1.024Serial1/0/0串行接口可以借用Loopback接口的IP地址和對(duì)端建立連接。10.1.1.1/32S1/0/0S1/0/0配置驗(yàn)證Page9[RTA]displayipinterfacebrief*down:administrativelydown^down:standby(l):loopback(s):spoofing……InterfaceIPAddress/MaskPhysicalProtocolLoopBack010.1.1.1/32upup(s)Serial1/0/010.1.1.1/32upupSerial1/0/1unassignedupdownPPP協(xié)議應(yīng)用Page10RTARTBPPPS1/0/0S1/0/0PPP協(xié)議是一種點(diǎn)到點(diǎn)鏈路層協(xié)議，主要用于在全雙工的同異步鏈路上進(jìn)行點(diǎn)到點(diǎn)的數(shù)據(jù)傳輸。PPP組件Page11名稱作用鏈路控制協(xié)議LinkControlProtocol用來建立、拆除和監(jiān)控PPP數(shù)據(jù)鏈路網(wǎng)絡(luò)層控制協(xié)議NetworkControlProtocol用于對(duì)不同的網(wǎng)絡(luò)層協(xié)議進(jìn)行連接建立和參數(shù)協(xié)商PPP鏈路建立過程Page12DeadEstablishAuthenticateTerminateNetworkUPFAILFAILOPENEDDOWNCLOSINGSUCCESS/NONEPPP幀格式Page13LCP報(bào)文封裝格式FlagInformationControlAddressFCSFlagProtocolTypeLengthData…TypeLengthData………CodeIdentifierLengthData…LCP報(bào)文配置參數(shù)的封裝格式Page14LCP報(bào)文Page15報(bào)文類型作用Configure-Request包含發(fā)送者試圖與對(duì)端建立連接時(shí)使用的參數(shù)列表Configure-Ack表示完全接受對(duì)端發(fā)送的Configure-Request的參數(shù)取值Configure-Nak表示對(duì)端發(fā)送的Configure-Request中的某些參數(shù)取值在本端不被認(rèn)可Configure-Reject表示對(duì)端發(fā)送的Configure-Request中的某些參數(shù)本端不能識(shí)別LCP協(xié)商參數(shù)Page16參數(shù)作用缺省值最大接收單元MRUPPP數(shù)據(jù)幀中Information字段和Padding字段的總長度1500字節(jié)認(rèn)證協(xié)議認(rèn)證對(duì)端使用的認(rèn)證協(xié)議不認(rèn)證魔術(shù)字魔術(shù)字為一個(gè)隨機(jī)產(chǎn)生的數(shù)字，用于檢測鏈路環(huán)路，如果收到的LCP報(bào)文中的魔術(shù)字和本端產(chǎn)生的魔術(shù)字相同，則認(rèn)為鏈路有環(huán)路啟用LCP鏈路參數(shù)協(xié)商Page17RTARTBPPP10.1.1.1/3010.1.1.2/30Configure-RequestConfigure-AckS1/0/0S1/0/0LCP鏈路參數(shù)協(xié)商Page18Configure-RequestConfigure-NakConfigure-Request(修改配置參數(shù))RTARTBPPP10.1.1.1/3010.1.1.2/30S1/0/0S1/0/0LCP鏈路參數(shù)協(xié)商Page19Configure-RequestRTARTBPPP10.1.1.1/3010.1.1.2/30Configure-RejectConfigure-Request(刪除某些參數(shù))S1/0/0S1/0/0PPP基本配置Page20[RTA]interfaceSerial1/0/0[RTA-Serial1/0/0]link-protocolpppWarning:Theencapsulationprotocolofthelinkwillbechanged.Continue?[Y/N]:y[RTA-Serial1/0/0]ipaddress10.1.1.130RTARTBPPP10.1.1.1/3010.1.1.2/30S1/0/0S1/0/0PPP認(rèn)證模式-PAPPage21Authenticate-Request明文發(fā)送用戶名和密碼Authenticate-Ack/Authenticate-Nak認(rèn)證成功/失敗認(rèn)證方

被認(rèn)證方S1/0/0S1/0/010.1.1.1/3010.1.1.2/30PPPRTARTB檢查被認(rèn)證方發(fā)送的用戶名和密碼信息是否正確PPP認(rèn)證模式-CHAPPage22ChallengeResponseSucess/FailureS1/0/0被認(rèn)證方S1/0/010.1.1.1/3010.1.1.2/30PPP認(rèn)證方RTARTB使用Challenge加密密碼信息使用Challenge加密密碼信息，與收到的加密密碼信息做比較IPCP靜態(tài)地址協(xié)商Page23S1/0/010.1.1.1/3010.1.1.2/30Configure-Request（10.1.1.1）Configure-AckConfigure-Request（10.1.1.2）Configure-AckS1/0/0PPPRTARTBIPCP動(dòng)態(tài)地址協(xié)商Page24Configure-Request（0.0.0.0）Configure-Nak（10.1.1.1）Configure-Request（10.1.1.2）Configure-AckConfigure-Request（10.1.1.1）Configure-AckS1/0/0S1/0/010.1.1.2/30PPPRTARTBPAP認(rèn)證Page25S1/0/0RTARTBPPP10.1.1.1/3010.1.1.2/30[RTA]aaa[RTA-aaa]local-userhuaweipasswordcipherhuawei[RTA-aaa]local-userhuaweiservice-typeppp[RTA]interfaceSerial1/0/0[RTA-Serial1/0/0]link-protocolppp[RTA-Serial1/0/0]pppauthentication-modepap[RTA-Serial1/0/0]ipaddress10.1.1.130[RTB]interfaceSerial1/0/0[RTB-Serial1/0/0]link-protocolppp[RTB-Serial1/0/0]ppppaplocal-userhuaweipasswordcipherhuawei[RTB-Serial1/0/0]ipaddress10.1.1.230S1/0/0被認(rèn)證方認(rèn)證方配置驗(yàn)證Page26<RTB>debuggingppppapallAug20201304:50:24.280.4+00:00RTBPPP/7/debug2:PPPStateChange:Serial1/0/0PAP:Initial-->SendRequest

Aug20201304:50:24.290.3+00:00RTBPPP/7/debug2:PPPStateChange:Serial1/0/0PAP:SendRequest-->ClientSuccess……配置CHAP認(rèn)證模式Page27[RTA]aaa[RTA-aaa]local-userhuaweipasswordcipherhuawei[RTA-aaa]local-userhuaweiservice-typeppp[RTA]interfaceSerial1/0/0[RTA-Serial1/0/0]link-protocolppp[RTA-Serial1/0/0]pppauthentication-modechap[RTB]interfaceSerial1/0/0[RTB-Serial1/0/0]link-protocolppp[RTB-Serial1/0/0]pppchapuserhuawei[RTB-Serial1/0/0]pppchappasswordcipherhuaweiS1/0/0RTARTBS1/0/010.1.1.1/3010.1.1.2/30PPP被認(rèn)證方認(rèn)證方配置驗(yàn)證Page28<RTB>debuggingpppchapallAug20201305:15:54.230.1+00:00RTBPPP/7/debug2:PPPStateChange:Serial1/0/0CHAP:Initial-->ListenChallengeAug20201305:15:54.230.7+00:00RTBPPP/7/debug2:PPPStateChange: