WideAreaNetworkingProtocolsPPT47(1)

WideAreaNetworkingProtocolsOverview1.0WideAreaNetworks2.0High-LevelData-LinkControlProtocol(HDLC)3.0Point-to-PointProtocol(PPP)4.0FrameRelay5.0IntegratedServicesDigitalNetwork6.0Dial-onDemandRouting(DDR)1.0WideAreaNetworks1.1IntroductiontoWideAreaServices1.2DefiningWANTerms1.2WANConnectionTypes1.3WANProtocols1.1IntroductiontoWideAreaServicesToextendLANstootherLANsatremotesitesConnectingsitestogethersoinformationcanbeexchangedServiceprovidersleaseorsharetheiralreadyinstalledconnections1.2DefiningWANTerms(WANServiceProviders)CustomerPremisesEquipment(CPE)Equipmentthatisownedandlocatedatthesubscriber’spremisesDemarcation(demarc)TheplacewheretheCPEendsandthelocalloopportionoftheservicebegins(usuallyinthe“phone-closet”)LocalLoopConnectsthedemarctotheclosestswitchingoffice(CO)CentralOffice(CO)/PointofPresence(POP)Connectsthecustomerstotheprovider’sswitchingnetwork.TollNetworkTheswitchesandfacilities,(trunks),insidetheWANprovider’s“cloud”.SynchronousserialAsynchronousserial,ISDNSynchronousserial1.3WANConnectionTypesDedicatedLeasedlines(PointtoPointConnection)Apre-establishedWANcommunicationspathfromtheCPE,throughtheDCEswitch,totheCPEoftheremotesite,allowingDTEnetworkstocommunicateatanytimewithnosetupproceduresbeforetransmittingdata.CircuitSwitchingSetsuplinelikeaphonecall.Nodatacantransferbeforetheend-to-endconnectionisestablished.Usedial-upmodemsandISDN.Itisusedforlow-bandwidthdatatransfers.PacketSwitchingSharebandwidthwithothercompaniestosavemoney.Fornotconstantlydatatransmission(otherwiseusingleasedline)TelephoneCompanyServiceProviderSpeedupto45MbpsLow-bandwidthdatatransfersSpeedrangefrom56Kto2.048M1.4WANProtocolsFrameRelayPacket-switchedtechnologywithDataLinkandPhysicalLayerspecificationProvideDynamic-bandwidthallocationandcongestioncontrolISDN(IntegratedServicesDigitalNetwork)VoiceandDatatransmissionoverexistingphonelinesHigherspeedthananalogdial-uplink;goodchoiceasabackuplinkLAPB(LinkAccessProcedure,Balanced)Aconnection-orientedprotocolattheDataLinklayerforusewithX.25Veryhighoverhead;onlyusediflinkisveryerrorproneHDLC(High-LevelDataLinkControl)DerivedfromSynchronousDataLinkControl(SDLC)createdbyIBMAconnection-orientedprotocolattheDataLinkLayer,lowoverheadEachvendor’sHDLCisproprietaryfortheirequipmentPPP(Point-to-PointProtocol)Anindustry-standardprotocol,tocreatepoint-to-pointlinksbetweendifferentvendor’sequipmentAllowauthenticationandmulti-linkconnections,runoverasyn.&syn.links2.0High-LevelData-LinkControlProtocol(HDLC)ISOstandard,bit-orientedDataLinklayerprotocolApoint-to-pointprotocolusedonleasedlinesDefaultencapsulationusedbyCiscoroutersoversynchronousseriallinks;ortypethefollowingcommandsRouter(config-if)#EncapsulationhdlcEachvendorhasadifferentwayfortheHDLCprotocoltocommunicatewiththeNetworklayerprotocolNoauthenticationSynchronousPhysicalMediaHDLCIPIPXAppleTalkBit-orientedprotocolsusesinglebitascontrolinformation(byte-orienteduseentirebyte)3.0Point-to-PointProtocol3.1IntroductiontoPPP3.2Point-to-pointProtocolStack3.3LinkControlProtocol(LCP)ConfigurationOptions3.4PPPSessionEstablishment3.5PPPAuthenticationMethods3.6ConfiguringPPPonCiscoRouters3.7VerifyingPPPEncapsulation3.1IntroductiontoPPPAData-link,point-to-pointprotocolusedOverasynchronousserial(dialup)Oversynchronousserial(ISDN,Leasedline)LCP(LinkControlProtocol)tobuildandmaintaindata-linkconnectionsUsetotransportlayer-3packetsacrossaData-linklayerComponents:EIT/TIA-232-C(formerlyRS-232)–physicallayerinternationalstandardforserialcommunicationHDLC–AmethodforencapsulatingdatagramsoverseriallinksLCP–Amethodofestablishing,configuring,maintaining,andterminatingthepoint-to-pointconnectionNCP–EncapsulatingdifferentNetworklayerprotocolacrossaPPPdatalink3.2Point-to-pointProtocolStackNetworkLayerIPIPXOthers,e.g.AppleTalkIPCPIPXCPOthers…DataLinkLayerNetworkControlProtocol(NCP)LinkControlProtocol(LCP)Authentication,otheroptionsHigh-LevelDataLinkControlProtocol(HDLC)PhysicalLayerSynchronousorAsynchronousPhysicalMedia(suchasEIA/TIA-232,V.24,V.35,ISDN)PPPServiceProviderTCP/IPAppleTalkPPPEncapsulationTCP/IPIPXAppleTalkIPX3.3LinkControlProtocol(LCP)ConfigurationOptionsLCPoffersPPPthefollowingoptions:AuthenticationPAP&CHAPCompressiontoincreasethethroughputofPPPconnection(Stacker&Predictor)ErrorDetectionQuality&MagicNumberMulti-linkstartinginIOS11.1SplitstheloadforPPPovertwoormoreparallelcircuits(bundle)3.4PPPSessionEstablishmentThreephasesofsessionestablishmentLink-establishmentphaseLCPpacketsaresentbyeachPPdevicetoconfigureandtestthelinkAuthenticationphase(optional)CHAPorPAPisusedtoauthenticatealinkNetwork-layerprotocolphaseNCPtoencapsulatemultipleNetwork-layerprotocolsandthensendoveraPPPdatalink3.5PPPAuthenticationMethodsPasswordAuthenticationProtocol(PAP)LesssecurePasswordsaresentincleartextOnlyperformupontheinitiallinkestablishmentWhenthePPPlinkisfirstestablished,theremotenodesentbacktheusernameandpasswordforauthenticationatthesendingrouterChallengeAuthenticationProtocol(CHAP)Usedattheinitialstartupofali