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IPv6inAmateurRadio BryanFields,W9CR StPetersburg,[email protected]:727Ͳ409Ͳ1194 Abstract AhistoricaloverviewoflegacyInternetprotocolsandtheirlimitationswillbepresentedhere.IPv6is theinternationallyͲrecognizedstandardreplacingtheseprotocols.AshortintroductiontoIPv6anda caseforitssupportintheamateurradiocommunityislacking.FinallyanoverviewofthecomingIPv6 deploymentinHamWANTampaBayispresentedasastudyofdeploymentforusebyradio amateurs.SomebackgroundinIPv4andInternetprotocolsisassumed. TableofContents Abstract...............................................................................................................1 IntroductiontoInternetProtocolUse..................................................................2 HistoryofIPv6/IPv4endtimes...................................................................................2 IPv6totherescue................................................................................................5 DifferenceFromIPv4..................................................................................................6 TypesofAddressspaceinIPv6...................................................................................8 DNS............................................................................................................................9 WhynotNAT?............................................................................................................9 Whatdoesthismeanforamateurradio............................................................10 CurrentstateofIPv6supportinAmateurradio........................................................10 SupportinAmateurRadioNetworks........................................................................11 AnIPv6StrategyforHamWAN..........................................................................12 Background..............................................................................................................12 IPv6NumberingPlan................................................................................................13 Partingthoughts................................................................................................14 [1] 23 IntroductiontoInternetProtocolUse TheInternetcurrentlyspeaksacommonprotocolsuiteknownasInternetProtocolVersion4, commonlyknownasIPv4.Thishasnotalwaysbeenthecase,asmanynetworkingprotocolsexistand havebeenrunontheInternet.PriortoFlagDay(Jan1,1983)NetworkControlProtocolwasthe protocolinuse.NCPhadmanylimitationsandtheupͲandͲcomingIPv4protocolwaschosento replaceit.OnFlagDayallNCPconnectionswereshutdownandIPv4connectionsbroughtupto replaceit.Inlessthan24hourstheentireInternetswitchedprotocols! Suchamassivechangetodaywouldbeimpossible. CurrentlytheInternetisfacingmajorlimitationstoIPv4: x Addressspace,only4.3Billionaddresspossible,7.4billionpeopleintheworld1 x Performanceissues(Difserv) x Securityandauthentication x Deploymentconfiguration x Routingtablebloat x Unequaldistributionofaddressspaceacrosstheglobe HistoryofIPv6/IPv4endtimes IPv4wasoriginallydesignedintheearly1980’swithitbeingformallycodifiedinRFC7912in1981.At thetimeacommoncomputerontheInternetwasa36bitPDPorHoneywellsystemwith10MBof diskandamegabyteofmemory.Thedecisionwasmadeearlyon3touse32bitsforaddressspace, whichwasthoughttoprovideavirtuallyunlimitedamountofspaceforthedozensofsitesonthe Internet. OfinteresttoAmateurradiooperatorsisRFC7904,theassignmentofnumbers.Thisisthefirstofficial recordof44/8beinggiventoAMPRNETonbehalfofHankMagnuski,KA6M.Thissmallrequestatthe timeendowedamateurradiowithanamazingresourcenowworthhundredofmillionsofdollars. ARDCisthecurrentownerofthisblockandaftermanyyearstheyareallowingsomelimiteduseof thisforamateurradiooperatorsdirectlyontheInternet. Fastforwardabittotheearly90sandtheInternethastakenoff;it’snolongerforresearchonly. Commercialusershavetakenoverandindividualuserscanbuyaccessover9600baudUnixshell dialupfor24.99permonth.Packetradioisboomingandamateurradioisdefiningstateoftheart. TherearesomeinitialrumblingsabouteventualexhaustionofIPv4numberspaceontheInternetand theeverͲimportantgrowthofroutingtablesonthelimitedIProutersoftheday. 1http://www.worldometers.info/worldͲpopulation/ 2https://tools.ietf.org/html/rfc791 3http://dltj.org/article/vintͲcerfͲipͲaddressing/ 4https://tools.ietf.org/html/rfc790 24 [2] IPv4allocationismanagedbyJonPostel56onaclassfulbasis;A,BorCblocks.Thereiswritingonthe wallthatclassBIPspacewillbeexhaustedinafewyears.WorkisstartedattheIETFtodevelopa solutiontothis;manyideasareproposedwithClasslessInterͲDomainRouting7beingthewinner. TheCIDR(pronouncedciderasinthefermentedappledrink)solutiondoesawaywiththeconceptof classfuladdressingandbreaksspacedownbasedonbitboundaries.Anorganizationcouldnow requesta/19fromIANAratherthanaclassBblock(/16)touseforconnectionsontheInternet. Theproblemnowturnedtoroutingastheprotocoloftheday,theExteriorGatewayProtocol(EGP) doesnotsupportCIDRblocks.Itlacksanumberoffeaturesandaredesignisbeingworkedpredating CIDR.ThereplacementroutingprotocolwouldbeknownasBorderGatewayProtocol(BGP).Thisis standardizedin1994asBGPversion48withCiscosupportingitinIOSversion10.0.TheInternet switchestousingthisprotocolinamaterofmonths.Thisprotocolisstillusedtoforroutingonthe Internet,over20yearslater. TheInternetisstillgrowingatanexponentialrate,andforthefirsttimeglobalroutingtablegrowthis becomingamajorissue.TheGRTisthetableofallactiveIPallocationsontheInternetmaintainedby arouterontheInternet.Everydirectlyattachedroutermustkeepafulltable(insomecasesmultiple copies)oftheseroutesinaspecialareaofmemory.By1996the64krouteboundarywascrossed anditwasstillclimbing.Mostroutervendorsarebarelyabletokeepupbyreleasingnewrouting enginessupportingthisgrowth. ContributingtothisisthepiecemealwayinwhichIPv4isallocated.Ratherthangeta/16and announceasingleroute,mostsitesstartedoffsmallwitha/19andgetanotherandanotheruntil theyhaveeight/19’s(equivalentinnumberofaddressestoa/16).Somethinghastobedone,and theIPng,“IPtheNextGeneration”workinggroupisstartedattheIETFtostudyreplacingIPv4witha newprotocol.Unfortunatelyroutingtablegrowthcontinuestogrowexponentially. InDecember1995IPngwasreleasedtotheworldasInternetProtocol,Version69.Thisis commentedonandextendedoverthenextfewyears,reachingproductionqualityin1998.Linux addssupportforIPv6inKernel2.1.8intheendof1996.ThegeneralconsensusistheInternetwill movetoIPv6bytheearly2000’s. IPv6isnotanextensiontoIPv4;itisanentirelynewprotocol.ThismeansIPv4andIPv6nodescan’t talkdirectlytoeachother.Themigrationstrategyproposediscalled“dualstack”,meaningeach routerandendnodewillrunIPv4andIPv6addressspaceatthesametime.Thisensuresconnectivity forbothprotocols,asIPv4wouldcontinuetobeusedforthenextcoupleyears,andplentyofIPv4 wasavailabletodualstack.AsthemassmigrationtoIPv6didn’tmaterialize,mostuserswerestuck inanIPv4Ͳonlyworld.Makingmattersworse,mostroutersandnetworksofthedayofferedabysmal 5https://en.wikipedia.org/wiki/Jon_Postel 6https://tools.ietf.org/html/rfc2468 7https://tools.ietf.org/html/rfc1519 8https://tools.ietf.org/html/rfc1771 9https://tools.ietf.org/html/rfc1883 [3] 25 IPv6performancewhencomparedtoIPv4performance.Thisperformancegapexisteduntil2014and stillpresentsitselfinsomeedgecasestothisday. Makingmattersworse,1996sawthedevelopmentofatechnologycalledNetworkAddress Translation,orNAT.ThisallowedaroutertouseonepublicIPorblockofIP’sandtranslateitso hundredsofnodesbehinditcouldaccessouttotheInternet.ForthefirsttimetheInternetisnow utilizedwithuniͲdirectionalconnectivity.AnodebehindaNATcanaccessothernodesonInternet butcannotbeaccessedfromtheInternet.ThisbreaksmultipleprotocolsandforcesallnewpeerͲtoͲ peerapplicationstoengageinNATtransversal.InmanycasesahelperserverontheInternetmust beusedtoconnectusersbehindaNAT.Forthefirsttime,thecoregoalofendͲtoͲendnetwork connectivityisbrokenontheInternet,thoughNATdoesslowIPaddressconsumptionslightly. Thedotcomcrashof2000Ͳ2001causesIPv6totakeabackseatonceagainasthepressureonIPv4 hasbeenreducedintheUS.IPv4isrunningandbeingdeployedatabreakͲneckpaceinAsiaduring thistime.IPv4addresslimitsarewellknowninAsiaandEuropeastheseareasoftheworldreceived about¼theIPv4spaceallocatedtotheUS.AsiaisoneoftheearlyadoptersofcombiningIPv4NAT andIPv6(NATͲPT)totheircustomers.ForthefirsttimearealIPv4addressonanInternetconnection isnowanadditionalcost. Thewritingisonthewall,butmanyUSͲbasedusersstillhavenointerestinIPv6deployment,and mostuserscannotgetIPv6eveniftheywantit.MostISP’shavecutbackandstartedtochargefor staticIPservice.SomesmallerUSISP’sstarttodeployNATbydefault.Cellularnetworksgodefault NATin,theexceptionsbeingthelargercarriers.AnexampleforthisinthecellularspaceisAlltel. Alltelhas40Msubscribers,with22Mactivedatausers;evenusingtheentire10/8IPv4spacetheydo nothaveenoughIP’sfortheircustomerbase.Theonlysolutionforaproviderofthissizeispublic IPv4.MostcanstillgetIPv4fromtheRIR’s,butit’sbecomemuchhardertojustifyandmorescrutiny appliedtotheapplicationswithARIN. “Idon’tneedIPv6;I’llbedeadbytimeIneedit.”isacommonphraseheard.In2008IANAandRIR’s developapolicyforIPv4exhaustion.TheplaniswhenIANAgetsdowntofive/8’sintheunallocated poolitwillgiveonetoeachofthefiveRIR’sandbeoutofunallocatedIPspace.ARINbeginstodraft policiesrelatedtoIPv4runoutforitsmembersandstartsanamedtransferprocess,whereaholder ofaddressescandesignateagivenrecipientofatransfer.ThisofficiallystartstheIPv4marketplace. OnMondayJanuary31,2011IANAallocatestwo/8blockstoAPNIC.Thisleavesfive/8blocksleftin thefreepool,triggeringtherunoutplanatIANA.OnThursdayFebruary3,2011IANAmakesthe announcement“TheIANAIPv4AddressFreePoolisNowDepleted”.10TheRIR’sstillhaveIPspace, butitslimitedandfinite.ARINhas2.5of/8’savailableofIPv4forallocationandtriggersitspolicy