無證書門限解密和無證書代理再加密.pdf

1、南京師范大學碩士學位論文無證書門限解密和無證書代理再加密姓名：朱俊申請學位級別：碩士專業(yè)：計算機應用技術(shù)指導教師：張福泰20100401AbstractAbstractIn2003，anewnotioncalled‘‘CerfificatelessPublicKeyCryptography(CLPKC)’’wasfirstpresentedbySattamSA1RiyamiandKennethGPatersonSattam『11Comp

2、ared、)l，itltraditionalpublickeycryptography(PKC)andidentitybasedcryptography(mc)，CLPKCmainlyhastwoadvantages：ItremovesthecostlycertificatemanagementwhichisnecessaryforthetraditionalpublickeycryptographyMeanwhile，itsolves

3、thekeyescrowproblemwhichisinherentinidentitybasedcryptographyCLPKCrepresentsallinterestingandpotentiallyusefulbalancebetweenidentitybasedcryptographyandtraditionalpublickeycryptographyInrecentyearsCLPKChasbecomeahotstudy

4、topicIndistributedsysterns，thresholdcryptosystemsareimportantandcanavoidsinglepointoffailureItiSusefulinthesituationwherepeopledon’tbelievethatanysinglepersoncanbetrusted‰sholddecryptionwhichdistributesthedecryptionpower

5、amonganumberofserversiSparticularlyusefulwherethecentralizationofthepowertodecryptisaconcernInthisthesiswefirstinvestigatetheissuesofthresholddecryptioninthescenarioofcertificatelesscryptographyWegiveacryptanalysisonthee

6、xistingcertificatelessthresholddecryptionschemeanddemonstratethatitisinsecureCombiningAIRiyamiandPaterson’Ssecuritymodelforcertificatelessencryptionschemeswiththenotionofthresholdcryptographyweintroduceastrongersecuritym

7、odelforcertificatelessthresholddecryptionschemesFurthermore，anewcertificatelessthresholddecryptionschemebasedonA1一RiyamiandPaterson’SccrtificatelessencryptionschemeispresentedOurschemeisnotonlyefficientineomputationandco

8、mmunicationbutalsoprovedsecureagainstchosenciphertextattackintheproposedfullyadaptiveadversarialmodelThesecurityproofispresentedin也erandomoraclemodelassumingthatanunderlyingproblemrelatedtotheBilinearDi銜eHellmanProblemis

9、computationallyhardSecondlywepresentthenotionsecuritymodelaswellasaconcretee伍cientschemeforcertificatelessproxyreencryption(CLPRE)Inaproxyre—encryption(PRE)scheme，asemi—trustedproxyisgivenspecialinformationthatallowsitto

10、transfornlciphertextsencryptedunderAIice’Spublickeyintothedifferentciphertexts也atcanbedecryptedbyBob’SsecretkeyIn2006GreenandAtenieseproposedanewidentitybasedproxyreencryptionsellemeinwhichciphertextsaretransformedfromon

11、eidentitytoanotherBasedonthis，weproposeournewconstructionforcertificatelessproxyreencryptionschemeandthecorrespondingsecuritymodelTheschemehaschosenplaintextsecurityintherandomoraclemodelassumingtheDecisionalBilinearDifi