第四章 點(diǎn)到點(diǎn)協(xié)議

第四章點(diǎn)到點(diǎn)協(xié)議（PPP）本章主題點(diǎn)到點(diǎn)協(xié)議鏈路控制協(xié)議配置選項(xiàng)配置PPP4.1PPP配置基礎(chǔ)PPP是一種可以用于異步（撥號(hào)）或同步串行（ISDN）介質(zhì)的數(shù)據(jù)鏈路層協(xié)議，它使用LCP建立并維護(hù)數(shù)據(jù)鏈路連接。4.1.1本節(jié)所討論的命令EncapsulationpppUsernamenamepasswordPppauthenticationchap|papShowinterface4.1.2實(shí)驗(yàn)七配置PPP鏈路4.1.2.1所需設(shè)備1）2500系列路由器兩臺(tái)；2）運(yùn)行終端仿真程序的PC一臺(tái)；3）一條CISCO扁平線纜；4.1.2.2拓?fù)浣Y(jié)構(gòu)Lo0Lo04.4.4.4/323.3.3.3/324.1.2.3配置需求1）要求在不使用用戶認(rèn)證的情況下使得R4,R3的回環(huán)接口能夠互相通信;2）使用PAP認(rèn)證方式進(jìn)行鏈路認(rèn)證；3）刪除PAP認(rèn)證方式，改用CHAP認(rèn)證方式進(jìn)行認(rèn)證；4.1.2.4配置步驟：第一步在CISCO路由器上配置PPP1）進(jìn)入接口配置模式，封裝二層協(xié)議PPP,配置IP地址；R4#shrunints1Buildingconfiguration...Currentconfiguration:81bytes!interfaceSerial1ipaddress172.16.3.4255.255.255.0encapsulationpppendR3#shrunints0Buildingconfiguration...Currentconfiguration:!interfaceSerial0ipaddress172.16.3.3255.255.255.0noipdirected-broadcastencapsulationpppclockrate64000end2）查看接口的封裝情況；R3#shints0Serial0isup,lineprotocolisupHardwareisHD64570Internetaddressis172.16.3.3/24MTU1500bytes,BW1544Kbit,DLY20000usec,reliability255/255,txload1/255,rxload1/255EncapsulationPPP,loopbacknotsetKeepaliveset(10sec)LCPOpenOpen:IPCP,CDPCPLastinput00:00:09,output00:00:09,outputhangneverLastclearingof"showinterface"counters00:05:59Inputqueue:0/75/0(size/max/drops);Totaloutputdrops:0Queueingstrategy:weightedfairOutputqueue:0/1000/64/0(size/maxtotal/threshold/drops)Conversations0/1/256(active/maxactive/maxtotal)ReservedConversations0/0(allocated/maxallocated)5minuteinputrate0bits/sec,0packets/sec5minuteoutputrate0bits/sec,0packets/sec60packetsinput,4246bytes,0nobufferReceived0broadcasts,0runts,0giants,0throttles0inputerrors,0CRC,0frame,0overrun,0ignored,0abort83packetsoutput,4238bytes,0underruns160outputerrors,0collisions,10interfaceresets0outputbufferfailures,0outputbuffersswappedout18carriertransitionsDCD=upDSR=upDTR=upRTS=upCTS=up使用debugppppackets打開調(diào)試程序；R3#00:47:17:Se0PPP:Ipkttype0xC021,datagramsize1600:47:17:Se0LCP:IECHOREQ[Open]id21len12magic0x10A273CA00:47:17:Se0LCP:OECHOREP[Open]id21len12magic0x00338DBA第二步配置可選的PPP認(rèn)證一一使用PAP協(xié)議在全局配置模式下配置用戶名和密碼注意：用戶名是遠(yuǎn)程路由器的主機(jī)名，雙方路由器的口令必須相同R4(config)#usernameR3passwordciscoR4(config)#R3(config)#usernameR4passwordciscoR3(config)#2）進(jìn)入接口配置模式，選擇PAP認(rèn)證方式R3#shrunBuildingconfiguration...Currentconfiguration:!version12.0servicetimestampsdebuguptimeservicetimestampsloguptimenoservicepassword-encryption!hostnameR3!enablepasswordcisco!usernameR4password0cisco!!interfaceSerial0ipaddress172.16.3.3255.255.255.0noipdirected-broadcastencapsulationpppclockrate64000pppauthenticationpapppppapsent-usernameR3password702050D480809!R4#shrunBuildingconfiguration...Currentconfiguration:835bytes!version12.1noservicesingle-slot-reload-enableservicetimestampsdebuguptimeservicetimestampsloguptimenoservicepassword-encryption!hostnameR4!loggingrate-limitconsole10excepterrorsenablepasswordcisco!usernameR3password0ciscoipsubnet-zeronoipfingernoipdomain-lookup!cnsevent-serviceserver!!interfaceSerial1ipaddress172.16.3.4255.255.255.0encapsulationppppppauthenticationpapppppapsent-usernameR4password70822455D0A16!在R4打開DEBUGPPPAUTHENTICATION命令，先關(guān)閉接口，在打開接口;R4(config)#00:59:31:Se1PPP:TreatingconnectionasadedicatedlineTOC\o"1-5"\h\z00:59:31:Se1PAP:OAUTH-REQid2len13from"R4"00:59:31:Se1PAP:IAUTH-REQid2len13from"R3"00:59:31:Se1PAP:IAUTH-ACKid2len500:59:31:Se1PAP:AuthenticatingpeerR300:59:31:Se1PAP:OAUTH-ACKid2len5R4(config)#第三步配置兩種可選的PPP認(rèn)證——首選CHAP，然后PAP1）在全局配置模式下配置用戶名和密碼注意：用戶名是遠(yuǎn)程路由器的主機(jī)名，雙方路由器的口令必須相同2）進(jìn)入接口配置模式，選擇CHAP和PAP認(rèn)證方式R4#shrunintsiBuildingconfiguration...Currentconfiguration:160bytes!interfaceSeriallipaddress172.16.3.4255.255.255.0encapsulationppppppauthenticationchappapppppapsent-usernameR4password713061E010803endR3#shrunints0Buildingconfiguration...Currentconfiguration:!interfaceSerialOipaddress172.16.3.3255.255.255.0noipdirected-broadcastencapsulationpppclockrate64000pppauthenticationchappapppppapsent-usernameR3password71511021F0725end3）打開DEBUGPPPAUTHENTICATION命令R4（config）#01:07:59:Se1PPP:Treatingconnectionasadedicatedline01:07:59:Se1CHAP:OCHALLENGEid2len23from"R4