简介:Aggregatesignaturesareausefulprimitivewhichallowsaggregatingmanysignaturesondifferentmessagescomputedbydifferentusersintoasingleandconstant-lengthsignatureandadaptstoMobileAdhocNETwork(MANETs)verymuch.JuminSong,etal.presentedanID-basedaggregatesignature,appliedittoMANETsandproposedasecureroutingscheme.Inthiswork,weanalyzeJuminSong,etal.’saggregatesignatureschemeandfindsomelimitationsonitsbatchverification.Inaddition,inthiswork,weapplyCraigGentry,etal.’sID-basedaggregatesignaturetoon-demandroutingpro-tocoltopresentasecureroutingscheme.Ourschemenotonlyprovidessoundauthenticationandasecureroutingprotocolinadhocnetworks,butalsomeetsthenatureofMANETs.
简介:Withouttheassumptionthattheprivatekeysarekeptsecureperfectly,cryptographicprimitivescannotbedeployedintheinsecureenvironmentswherethekeyleakageisinevitable.Inordertoreducethedamagecausedbythekeyexposureintheidentity-based(ID-based)signaturescenariosefficiently,weproposeanID-basedkey-insulatedsignatureschemeinthispaper,whicheliminatestheexpensivebilinearpairingoperations.Comparedwiththepreviouswork,ourschememinimizesthecomputationcostwithoutanyextracost.Underthediscretelogarithm(DL)assumption,asecurityproofofourschemeintherandomoraclemodelhasalsobeengiven.
简介:In2010,Hwang,etal.proposeda'DoS-resistantID-basedpasswordauthenticationschemeusingsmartcards'asanimprovementofKim-Lee-Yoo's'ID-basedpasswordauthenticationscheme'.Inthispaper,wecryptanalyzeHwang,etal.'sschemeandpointoutthattherevealedsessionkeycouldthreatthesecurityofthescheme.Wedemonstratethatextractinginformationfromsmartcardsisequaltoknowingthesessionkey.Thusknownsessionkeyattacksarealsoeffectiveundertheas-sumptionthattheadversarycouldobtaintheinformationstoredinthesmartcards.WeproposedanimprovedschemewithsecurityanalysistoremedytheweaknessesofHwang,etal.'sscheme.Thenewschemedoesnotonlykeepallthemeritsoftheoriginal,butalsoprovidesseveraladditionalphasestoimprovetheflexibility.Finally,theimprovedschemeismoresecure,efficient,practical,andconvenient,becauseellipticcurvecryptosystemisintroduced,theexpensivesmartcardsandsynchronizedclocksystemarereplacedbymobiledevicesandnonces.