中华电信研究所

我國6Bone規劃及建置經驗中華電信研究所前瞻技術研究室嚴劍琴中華民國八十九年十月十九日中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.ContentsIPv6通訊協定簡介WorldwideTestbed--6BoneIPv6推廣現況國外IPv6發展現況我國IPv6發展及建置經驗總結中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.IPv6通訊協定簡介中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.IntroductionDrivingmotivation:Limitationimposedbythe32-bitaddressinIPv4NAT(NetworkAccessTranslator)isashort-termsolutionbutnotthebestToprovideaplatformfornewInternetFunctionalityImprovementratherthanderivativeofIPv4AddressingCapacity,RoutingCapacity,SupportforQoS,Auto-configuration,Securityinter-operabilityandsoonRelatedIETFworkingGroupsIPng(ipngwg)workinggroupunderInternetAreaIPngTransition(ngtrans)workinggroupunderOperationsandManagementArea中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.IPv6vs.IPv4PacketDataUnitminimum20octetsmaximum65535octetsIPv4PDUFixed40octetsmaximum65535octetsIPv6PDU0ormoreIPv4HeaderDataFieldTransport-levelPDUIPv6HeaderExtensionHeaderExtensionHeader中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.DestinationAddressSourceAddressVerIHLServiceTypeIdentificationFlagsOffsetTTLProtocolHeaderChecksumSourceAddressDestinationAddressOptions+PaddingTotalLengthVerFlowLabelPayloadLengthNextHeaderHopLimitTrafficClassIPv4vs.IPv6HeaderIPv4PacketHeaderIPv6PacketHeader32bits中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.IPv6ExtensionHeaders(1/2)Hop-by-hopoptionsheaderRoutingheaderFragmentheaderAuthenticationheaderEncapsulatingsecuritypayloadheaderDestinationoptionsheaderIPv6PDUgeneralformTransport-levelPDUIPv6HeaderExtensionHeaderExtensionHeader40octets0ormore中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.IPv6ExtensionHeaders(2/2)IPv6specificationrecommendedorder:IPv6headerHop-by-hopoptionsheaderDestinationoptionsheaderRoutingheaderFragmentheaderAuthenticationheaderEncapsulationsecuritypayloadheaderDestinationoptionsheaderIPv6packetwithallextensionheadersOctets:40VariableVariableVariableVariableVariableVariable820(optionalvariablepart)=NextheaderfieldIPv6headerHop-by-hopoptionsheaderRoutingheaderFragmentheaderAuthenticationheaderEncapsecuritypayloadheaderTCPheaderApplicationdataDestinationoptionsheader中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.PacketFormatofIPv6vs.IPv4HeadersizebecomesfixedOptionfieldsarereplacedbyextensionheadershop-by-hop,routingheader,fragmentheader,authenticationheader,encapsulatingsecuritypayload,destinationoptionsheaderDecreasednumberoffield,increasedtotalsizeSixfieldsaresuppressedIPheaderlength,typeofservice,identification,flags,fragmentoffset,headerchecksumThreefieldsarerenamedTotallength:payloadlengthProtocoltype:nextheaderTimetolive:hoplimitTwofieldsareaddedtrafficclass,flowlabel中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.AddressingFeaturesAddressCapacity32-bitaddress128-bitaddressGivebrand-newstartforaddressaggregation(CIDR,ClasslessInter-DomainRouting)AddressingCapabilityUnicast,AnycastandMulticastAnycastaddressMoreefficientrouting(intermediatenodes)Moreefficientaccesstomirroredservers(destinationnodes)Singleinterfacewithmultipleaddresssupportrenumberinginanondisruptivemanner中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.RoutingCapabilitySizeofpacketheaderisfixedRevisedoptionmechanismMostbypassedbyroutersHintinheader(Routingoption)Thenumberoffieldsinpacketheaderisreduced12fixed+options8fixedSuppressed:headerlength,typeofservice,identification,flag,fragmentoffset,headerchecksumModified:length,protocoltype,timetoliveAdded:priority,flowlabelPacketfragmentationisnotallowedbyroutersPathMTU(Max.TransferUnits)discoveryprotocolAtleast1280octets中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.MoreFlexibleforQoSMechanismNew“Flow”conceptDefinedbysourceaddress+flowlabelRoutingonlyonflowDA,priority,hop-by-hop,routingoptionmustbethesameonagivenflowWhenusedwithRSVPDA+SA(+DP+SP)SA+flowlabelSolvelayerviolationwithroutersStillworkwithencryptionCanbeusedwithotherReservationProceduresDefineQoSofaflowinhop-by-hopoptions中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.OtherImprovementsMoreflexibleAutoconfigurationStatelessautoconfiguration(New)Statefulautoconfiguration(V6versionofDHCP,DynamicHostConfigurationProtocol)ImprovedSupportforSecurity,MobilityandARP,etc.Provideinter-operabilitymoreefficientprocess中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.TransitionMechanism(1/2)SimpleInternetTransition(SIT)Dual-stackstrategiesIPv6-over-IPv4TunnelingImportantfeaturesIncrementalupgradeanddeploymentMinimalupgradedependenciesEasyAddressingLowstart-upcostsTunnelingtechniquesConfiguredTunnelingTunnelendpointaddressshouldbedeterminedfromconfigurationinformationontunnelstartingpointForHost-to-RouterandRouter-to-Routertunnel中華電信研究所ChunghwaTelecomLabs.前瞻技術研究室AdvancedTechnologyLab.TransitionMechanism(2/2)AutomaticTunnelingIPv4-compatibleIPv6addressisusedasIPv6destinationaddressForHost-to-HostandRouter-to-HosttunnelIPv4TunnelDual-stacknod