ipv6典汇共存过渡策略

总体过渡总体过渡IPv4-IPv6•IPv4-IPv6•Awiderangeoftechniqueshaveidentifiedandimplemented,basicallyfallingintothreecategories:Dual-stacktechniques,toallowIPv4andIPv6toco-existinthesamedevicesandnetworksTranslationtechniques,toallowIPv6-onlydevicestocommunicatewithIPv4-onlydevicesExpectallofthesetobeused,in•IPv6UsingDualStackIPv6+DualStackIPv4+IPv6IPv4and/orIPv4PPIPv6UsingDualStackIPv6+DualStackIPv4+IPv6IPv4and/orIPv4PPIPv4configuredSomeorallinterfacesindualAllP+PEroutersarecapableofIPv4+IPv6IPv6configured••TwoIGPssupportingIPv4and•Memoryconsiderationsforlargerrouting•NativeIPv6multicast•AllIPv6trafficroutedinglobal•GoodforcontentdistributionandglobalservicesDualStackIPv6+DualStackIPv4+IPv6IPv4DualStackIPv6+DualStackIPv4+IPv6IPv4and/orIPv4PPipv6unicast-routinginterfaceEthernet0ipaddressipv6addressDualStackProtocolDualStackNodeDualStackProtocolDualStackNode•••BothIPv4andIPv6stacksApplicationscantalktoChoiceoftheIPversionisbasedonnamelookupandapplicationpreferenceDualStackApproach&=*Inadualstackcase，DualStackApproach&=*Inadualstackcase，anapplication–––IsIPv4andIPv6-CanquerytheDNSforIPv4and/orIPv6records(A)or(AAAA)Theapplicationchoosesoneortheother(thetypicaldefaultisIPv6)andthenrequeststhesourcehosttoconnecttothedestinationhostusingIPv6wwwINAwwwINAAAA2001:db8:1::1DNSQueryInQuery=“”Resp=“2001:db8:1::1”RouterDNSQueryInQuery=“”Resp=“2001:db8:1::1”RouterQuery=“”••DNSresolverpicksIPv6AAAArecordIPv6stacksonWindowsXP,Linux,FreeBSD,etcalsopickIPv6addressbeforeIPv4addressifbothexistDNS域名解析DNS域名解析顺••r1(config)#ipname-serverr1(config)#ipdomain-lookupr1#ping%Unrecognizedhostoraddress,orprotocolnot••••TunnelingTunnelingTunneling•Tunneling•••••ManualManualandGREManuallyConfiguredGREIPv4:IPv4:ManuallyConfiguredGREIPv4:IPv4:ipv6enableipv6address2001:db8:c18:1::2/128tunnelsourcetunneldestinationtunnelmodegreipipv6enableipv6address2001:db8:c18:1::3/128tunnelsourcetunneldestinationtunnelmodegreipManuallyConfiguredOverIPv4IPv6IPv4:ManuallyConfiguredOverIPv4IPv6IPv4:IPv4:ipv6enableipv6address2001:db8:c18:1::2/127tunnelsourcetunneldestinationtunnelmodeipv6ipipv6enableipv6address2001:db8:c18:1::3/127tunnelsourcetunneldestinationtunnelmodeipv6ip6to46to4isanaddressassignmentandrouter-router,host-to-router,androuter-to-automatictunnelingtechnologydefinedinRFC3056thatisusedtoprovideunicastIPv6connectivitybetweenIPv6sitesandhostsacrosstheIPv4Internet.6to4Tunnels(RFCIPv6IPv4BackboneIPv66to4Tunnels(RFCIPv6IPv4BackboneIPv6Backbone6to4PP•Automatictunnelmethodusing2002:IPv4::/48IPv6IPv4embeddedinIPv6formateg.2002:c80f:0f01::=•••••NoimpactonexistingIPv4orMPLSCore(IPv6TunnelendpointshavetobeIPv6andIPv4aware(Dualstack)Transitiontechnology–notforlongtermuseNomulticastsupport,StaticIntrinsiclinkagebetweendestinationIPv6SubnetandIPv4gatewayIPv4Gateway=TunnelEndDestinationDynamicallyIPv6IPv4BackboneIPv6Backbone6to4DestinationDynamicallyIPv6IPv4BackboneIPv6Backbone6to4PPAll6to4Networks16Host64ServerTunnelendpointinIPv4IPv6IPv46to4IPv6IPv4BackboneIPv66to4IPv6IPv4BackboneIPv6Backbone6to4PPinterfacetunnelipv6address2002:c80b:0b01::1/128tunnelsourceethernet0/0tunnelmodeipv6ipinterfaceethernetipaddressinterfaceethernetipv6addressipv6route2002::/16interfacetunnelipv6address2002:c80f:0f01::1/128tunnelsourceethernet0/0tunnelmodeipv6ipinterfaceethernetipaddressinterfaceethernetipv6addressipv6route2002::/166to4RelayIPv6IPv4BackboneBackbone6to4RelayIPv6IPv4BackboneBackbone2002:c058:6301::1IPv66to4PP2002:c058:6301::1IPv6••6to4relayallowsaccesstoIPv6globalCanusetunnelAnycastaddress6to4routerfindsclosest6-to-4relayrouterReturnpathcouldbeasymmetric•DefaultroutetoIPv6BGPcanalsobeusedtoselectparticular6to4relaybasedonprefixAllowsmoregranularroutingpolicy6to4RelayIPv6IPv4BackboneBackbone6to4RelayIPv6IPv4BackboneBackbone2002:c058:6301::16to4PP2002:c058:6301::1interfaceipaddressipv6address!interfaceipv6unnumberedLoopback2tunnelsourceLoopback2tunnelmodeipv6ip6to4!ipv6route2002::/16interfacetunnelipv6address2002:c80f:0f01::1/128tunnelsourceethernet0/0tunnelmodeipv6ipinterfaceethernetipaddressinterfaceethernetipv6addressipv6route2002::/16tunnel2002iproute::/0ISATAPISATAPisanaddressassignmentandhost-to-host-to-router,androuter-to-hosttunnelingtechnologydefinedinRFC4214thatprovidesunicastIPv6connectivityIntrasiteAutomaticIntrasiteAutomaticAddress••RFCThisisforenterprisenetworkssuchascorporateandacademicnetworksScalableapproachforincrementaltransport(NBMA)network••ISATAPAddress••ISATAPhostsuseaspecialIPV6addressInterfaceISATAPAddress••ISATAPhostsuseaspecialIPV6addressInterfaceIDcarries––Rightmost32bitscontainsthehostIPv4Leftmost32bitscontains“0000:5EFE”－－window7的为•GlobalprefixprovidedbyISATAP––InterfaceIDportionremainstaticforallLink-LocaladdressesusedforsolicitationofglobalHostInterfaceofHostCanbeLink-localorUnicastISATAPPrefixIPv4IPv4EnterpriseIPv6ISATAPPPQueryReplyRouterEncapsinISATAPPrefixIPv4IPv4EnterpriseIPv6ISATAPPPQueryReplyRouterEncapsinIPv4Dest:IPv6Dest:RouterEncapsinIPv4Dest:IPv6Dest:ISATAPNodesUse3IPv4IPv4EnterpriseIPv6ISATAPNodesUse3IPv4IPv4EnterpriseIPv6ISATAPPPIPv6Global:IPv6Global:ISATAPConfiguration(windowsIPv4IPv4EnterpriseIPv6ISATAPConfiguration(windowsIPv4IPv4EnterpriseIPv6ISATAPPP••PCconfigdoesnotuseEUI-64allowsroutertogenerateLinkIDportionofaddressTurnoffNDmessage•interfaceipaddress!interfaceipv6address2001:db8:face:2::/64eui-64noipv6ndsuppress-ratunnelsourceEthernet0tunnelmodeipv6ipisatapnetshinterfaceipv6isatapsetrouternetshinterfaceipv6isatapsetstate和合用和合用MPLSMPLSIPv6TransitUsingMPLS6PE(RFCIPv6MPLSIPv4IPv6PPIPv6TransitUsingMPLS6PE(RFCIPv6MPLSIPv4IPv6PPP•••6PEsmustsupportdualstackIPv4+IPv6(actsasnormalIPv4IPv6packetstransportedfrom6PEto6PEoverLabelSwitchIPv6addressesexistinglobaltableofPEroutersIPv6addressesexchangedbetween6PEusingMP-BGP••CoreusesIPv4controlplane(LDPv4,TEv4,IGPv4,MP-BenefitsfromMPLSfeaturessuchasFRR,ServicesUsingMPLSIPv6MPLSIPv4IPv6PP4ServicesUsingMPLSIPv6MPLSIPv4IPv6PP4P•••ConnectsIPv6islandsoverMPLScore(TransitsedgetoTransitionmechanismforprovidingunicastIPv6accessCoexistencemechanismforcombiningIPv4andIPv6servicesRoutingandLabelDistributionIPv6MPLSIPv4IPv64PP200.10.10PPRoutingandLabelDistributionIPv6MPLSIPv4IPv64PP200.10.10PPLDPv4Binds{Pop}toLDPv4Binds{27}LDPv4Binds{48}totoIPv6MP-LabelBinding{65}6PE•LDPOuterlabelthat6PE•LDPOuterlabelthatprovidesconnectivitytothedestinationMP-BGPInnerlabelusedbyegress6PEforIPv6BGPLabelalsoreferredtoas“AggregateIPv6Aggregatelabelsexecute“poplabel+IPv6lookup”ategressBGPNHisa“SpecialUse”IPv4toIPv6Mapped–•••IPv4of6PELabelIPv6MPLSIPv4IPv64PP200.10.10PPIPv6Prefix:BGPIPv4LDPIPv4BGPIPv66PELabelIPv6MPLSIPv4IPv64PP200.10.10PPIPv6Prefix:BGPIPv4LDPIPv4BGPIPv6IPv66PEIPv6MPLSIPv4IPv64PP200.10.10PPipv6!ipv6!interfaceipaddress!routerbgp100neighbor2001:DB8:1::1ip6PEIPv6MPLSIPv4IPv64PP200.10.10PPipv6!ipv6!interfaceipaddress!routerbgp100neighbor2001:DB8:1::1ipaddress!routerbgp2001:f00d:1::1remote-asremote-asremote-as100neighborneighborremote-asupdate-source!!address-familyaddress-familyactivate6PE2activate6PE12001:f00d:1::1activate2001:DB8:1::1activate6PEIPv6IPv6MPLSIPv4IPv6PP4200.10.106PEIPv6IPv6MPLSIPv4IPv6PP4200.10.10PP6PE-2#showipv6B2001:F00D::/64via::FFFF:,IPv6-6PE-2#showipv6cefinternal#hidden nexthopfasttagrewritewithF0/1,,tagsimposed{48TranslationTranslationTranslationScenariosandTranslationScenariosand•ThereisanongoingdemandfordevicesfromtheIPv4toaccessdevicesandviceDevicescanbeasingleIPv4orIPv6protocolstackDevicescanbedualstack,butMaybethenetworkinfrastructuredoesnotexistforeitherIPv4orMaybethereisIPv(x)capability,butisroutingnotMaybethedeviceisdualstack,buthasnoallocatedIPv(x)MaybethedevicehasaIPv(x)addressbutthenetworkdoesnotsupporttheprotocolIPv(x)?MaybenomoreuniqueIPv(x)addressesareavailable•••IPtranslationtechnologytakethesevariablesintoaccountforgenericorfocusedtranslationalProblemProblemIETFIPv4IETFIPv4ExhaustionandIPv6ConnectingIslandsofIPv4xoverIPv6xTunnelingtoanIPv4/IPv4NATCiscorelevance:L2TPLNS,6PE,CGSENAT,ASRNAT,ISRTranslatingIPv6toIPv4,IPv4toDifferencesbetweenNAT-PTandnewBEHAVEworkCiscorelevance:CGSENAT,ASRNAT,ISRNAT6AIBoFHomeGateBoFSoftwire’s“Dual-Stack•IPv4-over-IPv6tunneloverIPv6–TerminatesonlargeIPv4/IPv4NAT•LargeSoftwire’s“Dual-Stack•IPv4-over-IPv6tunneloverIPv6–TerminatesonlargeIPv4/IPv4NAT•LargeNATherefor–RemovesIPv6tunnelaesPublic–PerformsnormalIPv4/IPv4IP SubscriberIPv6prefixderivedfromIPv4address;AutomaticEncap&De