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SENSSSecurityServicefortheInternet

JelenaMirkovic(USC/ISI),Minlan Yu(USC),YingZhang(HPLabs),Sivaram Ramanathan (USC)

DDoS Attacks:LargeandPowerful

• DDoS attacksareincreasinginvolumeandfrequency(newrecord1.2Tbps)

• Disproportionatepowerinhandsofattacker– Attacksthatbringdownlarge,wellprovisionedvictimsoftenwieldedbyasinglepersonorsmallgroup(Spamhouse,Dyn,OVHandKrebs)

– Nospecialexperienceorcircumstance– Cheapforattacker,veryexpensiveforthevictim

• Enabledbylarge,distributedbotnets– Nosingleentity(centralizedordistributed)canwithstandthis,distributeddefensesamust

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Oursolution:SENSS

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• Fullysoftwaresolution– easytodeploy• EnablesanyISPtoofferautomated servicesfor

DDoS diagnosisandmitigation- Naturallydistributed,secure,robusttomisbehavior- WorkswithexistingISPinfrastructure(SDN,Flowspec,Netflow)

• VictimqueriesitsownISPorremoteISPs- Aboutitsinboundtraffic,routestoitsprefixes- Thishelpsdetectbestpointsformitigation

• VictimasksselectISPsto:- Filtersomeofitsinboundtraffic(victimspecifiesheadersignature)

- Demotearoutethatmaycontainabottleneck

SENSSModules

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A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

ST

client

clientserver

server

server

server

detector

detectorproxyblacklist aggregator

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SENSSAPIsatISPs

• ExposedasWebservices– Leverageexistingfunctionalitiesforrobustness(replication),

security(HTTPS),charging(e-commerce)

• Messageauthentication:Proofofauthorityforaprefix– E.g.,RPKI,aDBofknowncustomers,prefixesandpublickeys

• TLSforcommunicationsecurity

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Type Fields Action/ReplyTrafficquery Flow,dir,obs_time Listof<tag,dir,volume>

Trafficfilter/allow Flow,dir,tag,duration Deployfilter/allowactions

Routequery Prefix List ofbestpathstoprefix

Routedemote Prefix,segment,duration Demoterouteswithgivensegment

HowCanYouHelp?• Deployapassivemodule:

– Detector– learnhowoftenyouexperienceDDoS orparticipateinit

– Blacklistaggregator– getourfeedofsuspiciousprefixes• Deployanactivemodule:

– Server– automatefilterruledeploymentinmultipleswitches– Client+Detector– leverageyourISP’sDDoS solutionandtriggeritautomatically

• Lookingfor:– Experiencesfromtrenches,whatdoyoudonowforDoS?– One-timefeedbackonneeds,deployability,concerns– 1h/monthongoingfeedbackfromopsworld– Sitestopilotoursolutions

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Contactussunshine@isi.edu

http://steel.isi.edu/Projects/SENSS/

Jelena Mirkovic Minlan Yu Ying Zhang SivaramRamanathan