Software-Defined
T
Networking
T
(SDN)
T
and
T
Distributed
T
Denial
T
of
T
Service
T
(DDoS)
T
Attacks
T
in
T
Cloud
T
Computing
T
Environments:
T
A
T
Survey,
T
Some
T
Research
T
Issues
T
and
T
Challenges
Venkateswarlu
T
Bollapalli,
T
Katkireddy
T
Keerthana, Pundru
T
Sahithi, Pathpi
T
Pranaya
T
Reddy
AbstractT–
TATsophisticatedTstrategyTtoTorchestrateTstealthyTatta ckTpatternsTagainstTapplicationsTrunningTinTtheTclou d.TInsteadTofTaimingTatTmakingTtheTserviceTunavail able,TtheTproposedTstrategyTaimsTatTexploitingTtheTcl oudTflexibility,TforcingTtheTapplicationTtoTconsumeT moreTresourcesTthanTneeded,TaffectingTtheTcloudTcus tomerTmoreTonTfinancialTaspectsTthanTonTtheTservic eTavailability.TTheTattackTpatternTisTorchestratedTinT orderTtoTevade,TorThowever,TgreatlyTdelayTtheTtechni quesTproposedTinTtheTliteratureTtoTdetectT low-rateTattacks.TItTdoesTnotTexhibitTaTperiodicTwavefor mTtypicalTofT
low-rateTexhaustingTattacks.TInTcontrastTwithTthem,TitTis TanTiterativeTandTincrementalTprocess.TInTparticular, TtheTattackTpotencyT(inTtermsTofTserviceTrequestsTra teTandTconcurrentTattackTsources)TisTslowlyTenhance dTbyTaTpatientTattacker,TinTorderTtoTinflictTsignifica ntTfinancialTlosses,TevenTifTtheTattackTpatternTisTper formedTinTaccordanceTtoTtheTmaximumTjobTsizeTand TarrivalTrateTofTtheTserviceTrequestsTallowedTinTthe Tsystem.TUsingTaTsimplifiedTmodelTempiricallyTdesig ned,TweTderiveTanTexpressionTforTgraduallyTincreasi ngTtheTpotencyTofTtheTattack,TasTaTfunctionTofTthe TreachedTserviceTdegradationT(withoutTknowingTinTa dvanceTtheTtargetTsystemTcapability).TWeTshowTthatT theTfeaturesTofferedTbyTtheTcloudTprovider,TtoTensur
eTtheTSLATnegotiatedTwithTtheTcustomerT(includingT theTloadTbalancingTandT
auto-scalingTmechanisms),TcanTbeTmaliciouslyTexploitedTb yTtheTproposedTstealthyTattack,TwhichTslowlyTexhaust sTtheTresourcesTprovidedTbyTtheTcloudTprovider,Tand TincreasesTtheTcostsTincurredTbyTtheTcustomer.
1.INTRODUCTION
InTthisTpaper,TweTstudyTcloudTcomputingTisTaT newTtrendTafterTgrids.TManyT
market-basedTresourceTmanagementTstrategiesTareTbeenT broughtToutTtoTimplementTresourceTschedulingTi nTcloudTcomputingTenvironment.TMoreTandTmor eTconsumersTrelyTonTcloudTprovidersTtoTsupply TcomputingTservice,TsoTeconomicTeffectivenessTb ecomeTcrucialTdecisiveTfactorTforTschedulingTpol icy.TInTthisTpaperTweTdesignedTanTeconomicTsc hedulingTmodelTwithTbusinessTparameters.TAndT aTdynamicTschedulingTalgorithmTwasTpresented,T whichTmadeTaT
trade-offTbetweenTeconomicTeffectivenessTandTperform ance.TBasedTonTtheTmodelTandTalgorithm,TweTb roughtToutT
nsumers'TdemandsTandTimproveTschedulingTeffici ency.ATstrategyTtoTorchestrateTstealthyTattackTpat terns,TwhichTexhibitTaT
slowly-increasing-intensityTtrendTdesignedTtoTinflictTtheTmaximum TfinancialTcostTtoTtheTcloudTcustomer,TwhileTres pectingTtheTjobTsizeTandTtheTserviceTarrivalTrate TimposedTbyTtheTdetectionTmechanisms.TWeTdes cribeTbothThowTtoTapplyTtheTproposedTstrategy, TandTitsTeffectsTonTtheTtargetTsystemTdeployedT inTtheTcloud.InsteadTofTaimingTatTmakingTtheTs erviceTunavailable,TtheTproposedTstrategyTaimsTa tTexploitingTtheTcloudTflexibility,TforcingTtheTap plicationTtoTconsumeTmoreTresourcesTthanTneede d,TaffectingTtheTcloudTcustomerTmoreTonTfinanci alTaspectsTthanTonTtheTserviceTavailability.TTheT attackTpatternTisTorchestratedTinTorderTtoTevade, TorThowever,TgreatlyTdelayTtheTtechniquesTpropo sedTinTtheTliteratureTtoTdetectT
low-rateTattacks.TItTdoesTnotTexhibitTaTperiodicTwav eformTtypicalTofT
low-rateTexhaustingTattacks.TInTcontrastTwithTthem,Ti tTisTanTiterativeTandTincrementalTprocess.TInTpar ticular,TtheTattackTpotencyT(inTtermsTofTserviceT requestsTrateTandTconcurrentTattackTsources)TisTs lowlyTenhancedTbyTaTpatientTattacker,TinTorderT toTinflictTsignificantTfinancialTlosses,TevenTifTthe TattackTpatternTisTperformedTinTaccordanceTtoTt heTmaximumTjobTsizeTandTarrivalTrateTofTtheTs erviceTrequestsTallowedTinTtheTsystem.TUsingTa TsimplifiedTmodelTempiricallyTdesigned,TweTderi veTanTexpressionTforTgraduallyTincreasingTtheTp otencyTofTtheTattack,TasTaTfunctionTofTtheTreac hedTserviceTdegradationT(withoutTknowingTinTad vanceTtheTtargetTsystemTcapability).TWeTshowTt hatTtheTfeaturesTofferedTbyTtheTcloudTprovider,T toTensureTtheTSLATnegotiatedTwithTtheTcustome rT(includingTtheTloadTbalancingTandT
auto-scalingTmechanisms),TcanTbeTmaliciouslyTexploit edTbyTtheTproposedTstealthyTattack,TwhichTslowl yTexhaustsTtheTresourcesTprovidedTbyTtheTcloud Tprovider,TandTincreasesTtheTcostsTincurredTbyTt heTcustomer.
2.RELATEDTWORK
Recently,TthereTareTsomeTofTproposedTsolutionsT thatThaveTbeenTcreatedTtoTdiminishTtheTeffectTo fTtheTsecurityTissuesTinTSDN.THowever,TaTlittle TnumberTofTthemTconcentratesTenoughTonTtheT mechanismsTtoTdefenseTagainstTDDoSTattack. InTcloudTcomputingTalsoTpartialTserviceTdegradat ionTdueTtoTanTattackThasTdirectTeffectTonTtheTs erviceTcosts,TandTnotTonlyTonTtheTperformanceT andTavailabilityTperceivedTbyTtheTcustomer.TThe TdelayTofTtheTcloudTserviceTproviderTtoTdiagnos eTtheTcausesTofTtheTserviceTdegradationT(i.e.,Tif TitTisTdueTtoTeitherTanTattackTorTanToverload)T canTbeTconsideredTasTaTsecurityTvulnerability.TIt TcanTbeTexploitedTbyTattackersTthatTaimTatTexh austingTtheTcloudTresourcesT(allocatedTtoTsatisfy TtheTnegotiatedTQoS),TandTseriouslyTdegradingTt heTQoS,TasThappenedTtoTtheTBitBucketTCloud,T whichTwentTdownTforT19h.TTherefore,TtheTcloud TmanagementTsystemThasTtoTimplementTspecific TcountermeasuresTinTorderTtoTavoidTpayingTcred itsTinTcaseTofTaccidentalTorTdeliberateTintrusionT thatTcauseTviolationsTofTQoSTguarantees.T
3.FRAMEWORK 3.1TSoftwareTDefinedTNetworking:
sTApplicationTlayer,TControlTlayer,TandTInfrastru ctureTlayer.TTheTapplicationTlayerTcontainsTappli cationsTthatTcontrolTtheTnetworkTthroughTtheTno rthTboundTinterface.TTheTcontrolTlayerTcontainsT anTinterfaceTtoTapplicationsTofTtheTnetworkTitem sTonTtheTinfrastructureTlayerTthroughTaTsouthTb oundTinterface.TTheTinfrastructureTlayerTcontains TnetworkTitemsTsuchTasTaccessTpointsTandTswitc hes.TTheseTitemsTplayTanTimportantTroleTtoTfor wardTaTpacketTorTdropTit.
TInTSDN,TtheTOpenFlowTprotocolTisTresponsible TforTtheTcommunicationTbetweenTtheTcontrollerT andTtheTOpenFlowTswitchesTthroughTtheTsecureT channel.TOpenFlowTdefinesTtheTbehaviorTofTtheT
low-levelTpacketTforwardingTinTtheTdataTplane.TEach TnetworkTdevicesThasTaTflowTtableTthatTincludes TflowTentriesTinTtheTOpenFlowTprotocol.TWhenT aTnewTpacketTreachesTtheTswitch,TitTwillTmatch TinTitsTtables.TTheTpacketTwillTbeTtransmittedTa sTtheTinstructionsTinTtheTtableTifTaTmatchTisTfo und.TOtherwise,TtheTpacketTwillTbeTforwardedTf orTtheTpurposeTofTprocessingTinTtheTcontroller.
Fig:TArchitectureTviewTofTSDN
InTaTcaseTofTaTDDoSTattacks,TtheTspoo fedTaddressesTinTpacketTwillTnotThaveTaTmatch TinTtheTtable,soTtheyTwillTbeTsentTtoTtheTcontro llerTforTprocessing.TAllTresourcesTwithTinTtheTc ontrollerTwillTtendTtoTprocessTmalignantTpackets
TifTtheTaccessTratesTofTpacketsTtoTtheTcontroller TisThigh.TTheTcontrollerTcouldTbeTcompletelyTo verwhelmedTwithTaThighTrateTattackTwhichTmak eTitTunreachableTtoTtheTlegitimateTusers.TThisTc ouldTbeTleadsTtoTdestroyTtheTSDNTarchitectureT ofTtheTnetwork.
3.2TPossibleTDDoSTattacksTinTSDN:
DetectionTmethodsTofTDDoSTattacksTinvestigated TasTaTresearchTtopicTforTanTalmostTlongTterm,T butTlimitedTresearchTregardingTsecurityTissuesTin TSDNTenvironments.TSDNTprovidesTaTgreatTdeal TtoTmitigateTDDoSTattacksTinTcloudTcomputingT environments,TbutTmanyTsecurityTissuesTstillTuns olvedTinTSDNTitself.TThisTsectionTfocusesTonTD DoSTattacksTandTdiscussesThowTSDNTitselfTcan TbeTaTvictimTforTDDoSTattacks,TthenToffersTbri efTsummaryTaboutTavailableTsolutions.T
Fig:TPotentialTDDoSTattacksTinTSDN’sTArchit ecture
ApplicationTLayerTDDoSTattacks:TTwoTtypesT ofTattacksTcanTbeTlaunchedTonTapplicationTlayer TincludingTtheTattackTonTapplications,TorTtheTatt ackTonTnorthboundTAPI.TDDoSTattacksTonToneT applicationTcanTaffectTotherTapplications,TdueTto TisolateTofTresourcesTorTapplicationsTinTSDN.T
ControlTLayerTDDoSTattacks:TTheTcontrollerTi nTSDNTarchitectureTcouldTbeTseenTasTsingleTpoi ntTofTfailureTforTtheTnetwork,TwhichTisTaTtarget TforTDDoSTattacks.TSeveralTtypesTofTattacksTca nTbeTlaunchedTonTcontrolTlayer:TattackingTtheTc ontroller,TtheTnorthboundTAPI,TtheTsouthboundT API,TtheTwestboundTAPI,TorTtheTeastboundTAPI. T
InfrastructureTLayerTDDoSTattacks:TTwoTtype sTofTattacksTcanTbeTlaunchedTonTinfrastructureTl ayerTincludingTattackTswitchesTorTattackTtheTsou thboundTAPI.TForTinstance,TwhenTonlyToneThea derTinformationTisTtransferredTtoTtheTcontroller,T theTpacketTshouldTbeTsavedTinTnodeTmemoryTu ntilTre-enteringTtheTflowTtable.T
4.TEXPERIMENTALTRESULS
DefenseTMechanismsTagainstTDDoSTattacksTUsingTSDN:T
ThisTsectionTdescribesTtheTfeaturesTofTSDNTthat TcontributedTtoTmitigatingTDDoSTattackTalsoToff ersTanToverviewTofTtheTavailableTmethodsTthrou ghTSDNTtoTdefeatTDDoSTattack.
4.1TFeaturesTofTSDNTtoTDefeatTDDoSTAttacks
SDNToffersTaTnewTnetworkTarchitectureTforTclo udTcomputing,TwhichTbroughtTmanyTadvantagesT toTdetectingTDDoSTattacks.TTheseTfeaturesTofTS DNTasTfollows:T
TheTcontrolTandTdataTplanesTareTdec oupled:TInTSDN,TtheTnetworkTdevicesT didTnotThaveTcontrolTfunctionality,TandT theyTbecameTaTsimpleTforwardingTeleme nt.T
ForwardingTdecisionsTareTflowTbased:
TATsetTofTpacketTfieldTvaluesTandTaTse tTofTactionsTareTdefinedTasTaTflow.TThe TflowTinTtheTSDNTisTaTsequenceTofTpa cketsTbetweenTaTsourceTandTaTdestinatio n.TFlowTprogrammingTallowsTunpreceden tedTflexibility,TwhichTisTlimitedTonlyTto TtheTflowTcapabilitiesTinTtheTimplementi ngTtables.T
TheTTransferTofTtheTlogicalTcontroller
TtoTanTexternalTentity:TTheTpurposeTo fTtheTcontrollerTisTsimilarTtoTthatTofTaT traditionalToperatingTsystem,TwhichTprovi desTtheTbasicTresourcesTandTabstractions TaccordingTtoTaTlogicalTcentralizedTforT helpingTtheTprogrammingTofTforwardingT devicesTbasedTonTabstractTnetworkTview TandTaTlogicalTcentralized.T
AdvantagesTofTS
DN AdvantagestigatingTDDoSTforTTattami ck
DecoupleTtheTcon trolTplaneTandTth eTdataTplane.
ItTcanTbuildTupThug eTscaleTattackTandTr esistanceTexperiment sTreadily.
DynamicTupdating TofTforwardingTd ecisions.
ItTcontributesTtoTrea ctTexpeditiously.
TheTtransferTofTt heTlogicalTcontrol lerTtoTanTexternal Tentity.T
ItTconstructsTreliable TsecurityTpolice.
TheTnetworkTisTp
rogrammable. ItedureTunderpinsTofTharvestingTaTproc TinsightTfromTcurre ntTIDSs.
TableT1:TAdvantagesTofTSDNTtoTmiti gatingTDDoSTattack
4.2TDefenseTMechanismsTofTSDN
TAsTpreviouslyTdescribed,TSDNThasTaTl otTofTfeaturesTthatTprovideTnewTchances TtoTdefeatTDDoSTattacksTwhichTcontribu teTtoTbuildingTgoodTdefenseTmechanisms. TFirst,TthisTpartTprovidesTmoreTdetailsTa boutTthisTfeatureTandTthenTTableT2Tsum marizesTtheTdefenseTmechanismsTthatTus edTbyTSDNTagainstTDDoSTattacksTandT brieflyTdescribesTsomeTproposedTmethods TinTrelatedTworks.TTheTmechanismsTofT SDNTclassifiedTintoTthreeTsegments,Twhi chTareTbasicallyTbuiltTbasedTonTtheTnew TfeaturesTofTSDN.T
SeparationTofTtheTcontrolTpla neTfromTtheTdataTplane:TDec oupledTtheTdataTplaneTandTthe TcontrolTplaneTinTSDN,Twhich TmakingTpossibleTtoTestablishT wideTrangingTattackTandTdefens eTexperiments.THighTconfigurabi lityTofTSDNToffersTclearTsepara tionTamongTvirtualTnetworksTpe rmittingTexperimentationTonTaTr
ealTenvironment.TThroughTaTsm oothTtransitionTfromTexperiment alTphaseTtoToperationalTphaseTc anTdeployTnewTideasTprogressiv ely.TThisTfeatureTofTSDNTcontr ibutedTinTputtingTforwardTnewT ideasTandTmethodsTtoTmitigateT DDoSTattacks.
ATlogicalTcentralizedTcontrolle rTandTviewTofTtheTnetwork:T InTSDN,TtheTcontrollerTbuildsT consistentTsecurityTpoliciesTthro ughTitsTnetworkTwideTknowledg eTofTtheTsystemTtoTmonitorTor TanalyzeTtrafficTpatternsTforTpo tentialTsecurityTthreats.TTheTinf ormationTobtainedTthroughTrequ estingTendThostsTandTremoteTa uthenticationT
dial-inTuserTserviceTserversTforTuser ’sTauthenticationTinformationTan dTsystemTscanningTduringTregis tration,TmakesTitTpossibleTforTc entralizedTcontrolTofTSDNTtoTd ynamicallyTquarantineTcompromi sedThostsTandTauthenticateTlegit imateThosts.T
ProgrammabilityTofTtheTnetw orkTbyTexternalTapplication:T TheTprogrammabilityTofTSDNTs upportsTaTprocessTofTharvesting TintelligenceTfromTexistingTIntr usionTDetectionTSystemsT(IDSs) TandTIntrusionTPreventionTSyste msT(IPSs).
Software-basedTtrafficTanalysis:TAnalysi sTofT
software-basedTtrafficTenablesTinnovation, TasTitTisTpossibleTtoTuseTallTt ypesTofTintelligentTalgorithms,T databases,TandTanyTotherTsoftw areTtoolsTinTorderTtoTimproveT theTcapabilitiesTofTaTswitch. DynamicTupdatingTofTforward
orkTinTtheTformTofTflowTrules TtoTblockTtheTattackTtrafficTwit houtTdelayTfromTenteringTandT propagatingTinTaTnetwork.
M e c h a n i s m s
DescriptionTo fTmechanisms
T SD NT per for ma nce
RelatedTwork s S o u r c e -b a s e d T m e c h a n i s m s
AllowTSDNTc ontrollersTiden tifyingTabnorm alityTtraffic,Tfi lteringTtheTma levolentTpacke tTorTexaminin gTtheTsourceT IPTaddressTne arTtoTtheTentr anceTofTtheTn etwork.
An aly sis Tth eTt raff ic
TheTbaseTstati onTthatTcontr olledTbyTanT OpenFlowTuse dTtoTanalysis TtheT real-timeTtrafficTin TorderTtoTdet ectTportableT malware. Pro gra m ma bili tyT
UsingTtheTfea tureTofTSDNT whichTisTprog rammability,Tt heTprogramma bleTofTaThom eTnetworkTro uterTthatTuseT OpenFlow-compatibleTsw itchesTtoTdete ctTsecurityTpr oblemsTinTaT smallThomeTo rToffice. N e t w o r k -b a
DetectTDDoST attacksTaccordi ngTtoTtrafficT flow.T
An aly sis Tth eTt raff icT wit hT cen
IdentifyTtheTtr afficTpatternTi sTnormalTorT malevolentTthr oughTstatistica lTdataTinTthe TflowTtable.
s e d T m e c h a n i s m s tral Tc ont rol Pro gra m ma bili ty
AnTOpenFlow TsecurityTappl icationTthatTc anTprovideTpr ogrammingTfr ameworkTisTp roposed. D e s ti n a ti o n -b a s e d T m e c h a n i s m s
UtilizedTIPTtr aceTbackTtoTd iscoverTtheTso urceTandTpath TtheTflowTofT attacks,Thowev er,TmostTmeth odologiesTforT IPTtraceTback TareTdifficultT toTbeTdeployT onTtheTinterne t. Up dat eT ofT dy na mi cT pri nci ple s
AnTincrement allyTdistribute dTmethodTacc ordingTtoTsam pledTflowsTfo rTIPTtracebac k,TitTisTnotTi mportantTatTr outersTtoTdepl oyTspecificTtr acebackTsoftw areTandThard ware. Ce ntr alT con trol Tw ith Tgl oba lTv iew s
NetSightTisTa nTextensibleT platformTwhic hTempowersT applicationsTto TrecoverTtheT packetThistorie s.T
TableT2:TTheTdefenseTmechanismsTagainstTD DoSTattacksTusingTSDN.
5.TCONCLUSION
low-rateTattacks.TExploitingTaTvulnerabilityTofTtheTta rgetTapplication,TaTpatientTandTintelligentTattacke rTcanTorchestrateTsophisticatedTflowsTofTmessage s,TindistinguishableTfromTlegitimateTserviceTreque sts.TInTparticular,TtheTproposedTattackTpattern,Tin steadTofTaimingTatTmakingTtheTserviceTunavaila ble,TitTaimsTatTexploitingTtheTcloudTflexibility,Tf orcingTtheTservicesTtoTscaleTupTandTconsumeTm oreTresourcesTthanTneeded,TaffectingTtheTcloudTc ustomerTmoreTonTfinancialTaspectsTthanTonTtheT serviceTavailability.
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Venkateswarlu Bollapalli, Assistant Professor Department of Information Technology, Guru Nanak Institutions Technical Campus, Hyderabad.
KatkireddyTKeerthana, B.Tech Scholar, Department of Information Technology, Guru Nanak Institutions Technical Campus, Hyderabad
PundruTSahithi, B.Tech Scholar, Department of Information Technology, Guru Nanak Institutions Technical Campus, Hyderabad