利用云系统实现电子健康档案的机密性(IJCNIS-V10-N1-3)

I.J.ComputerNetworkandInformationSecurity,2018,1,18-25PublishedOnlineJanuary2018inMECS()DOI:10.5815/ijcnis.2018.01.03Copyright©2018MECSI.J.ComputerNetworkandInformationSecurity,2018,1,18-25AchievingConfidentialityinElectronicHealthRecordsusingCloudSystemsRobertFrench-BaidooTakoradiTechnicalUniversity,GhanaE-mail:[e-mail]enOpokuOppongDepartmentofComputerScience,KNUST,Ghana;FacultyofInformatics,GTUC,GhanaE-mail:[e-mail];[e-mail]:26August2017;Accepted:13October2017;Published:08January2018Abstract—Currently,existingmethodsforenforcingaccesstorecordsinanElectronicHealthRecordsystemreliesonasingleTrustedServerwhichstoreshealthrecordsandmediatesaccess.SuchTrustedSeversemployeitheraCiphertext-PolicyAttribute-BasedEncryption(CP-ABE)orKey-PolicyAttribute-BasedEncryption(KP-ABE)methodforstoringandcontrollingaccess.However,TrustedServerstorageofhealthrecordsissusceptibletosingle-point-of-threatattackandasuccessfulattackinvariablyleadstocompromisingtheintegrityofrecordsontheserver.Inthisresearchwork.ThispaperpresentsamethodologythatdefinesandcreatessimpleAccessStructuresandeliminatesneedforprivatekeysduringencryptionand/ordecryptionofhealthrecordswhichistheEnhancedCiphertext-PolicyAttribute-BasedEncryption(ECP-ABE).TheECP-ABEyieldshighcryptographicperformancecreatessimpleAccessStructures,eliminatesneedforprivatekeysandpresentsanimplementationarchitecturethatmakescloud-basedEHRsystemsecureandconfidential.TheECP-ABEalsoperformscryptographicfunctionsusinglessCPUtime,minimalcomputermemoryandproduceshighencryptionanddecryptionthroughputespeciallywithincreasingfilesizes.IndexTerms—TrustedAuthority,AdvanceEncryptionSystem256,SecureHashingAlgorithm256,VirtualElectronicMedicalRecords,PublicKeyInfrastructure,PublicKeyGenerator,RandomAccessMemory.I.INTRODUCTIONThequesttostorehealthrecordselectronicallysothatmanagementofsuchrecordscanbedoneinawell-structuredmannerhasreceivedlotsofattentionlately.Cloud-basedelectronichealthrecordssystemguaranteesround-the-clockrecordsavailabilityregardlessofyourgeographicallocation.ElectronichealthmanagementsystemsmaybeintheformofElectronicHealthRecords(EHR),wheresensitivehealthrecordsofpatientsaregathered,storedandmanagedbyanenterprisesuchahospital,orintheformofPersonalHealthRecords(PHR)wherepatientspurchasetheserviceofathird-partystoragefacilityserviceprovidersothatthepatientcancreate,updateandgenerallymanagetheirownhealthrecordsindependently.Thethirdisahybridsystemwherehealthcarefacilitiesandpatientsplaytheroleofcollectinghealthinformationofpatients,updatingandmanagingthoserecordsintandem.Eachpartyinthehybridsystemhasvaryinglevelsofrightsandprivilegesaccruingtohimorher[1].Unfortunately,cloudserviceproviderswhoaretrustedtosecurestoredrecordshavenotliveduptotask.Twentypercentofhealthcareprovidershavesufferedsecuritybreachesbetweentheyears2009and2013,andaboutFiveHundredhealthrecordshavebeenbreachedthrough804attacks[2].Securityanddataconfidentialityremainsthebiggestthreattoelectronichealthsystems;attacksoncloudsystemsarerelentless.Inappropriateuserrightdefinitionsandpermissions,ineffectiveaccessstructuredefinition,andinsecureimplementationdesignaresomeoftheproblemsbedevilingelectronichealthrecordsystems.II.REALTEDWORKSRelatedtechnologiesarepresentedinthissection.A.HealthInformationPrivacyHealthInsurancePortabilityandAccountabilityAct(HIPAA)1996addressestwomajorissues;PrivacyRuleandSecurityRule.TheHIPAAdocumentdescribesreasonableprocedurestopreventexposureofprotectedhealthinformation[3].TheActcouldnotdealwithprivacymattersrelatingtohealthinformation.Researcherslookedatcryptographytoaddresshealthprivacyandsecuritygapsinthepolicy.Cryptographyisusedininsecureenvironmenttostoreandscrambledatasothatonlyqualifiedpersonscanaccess,readandprocessdata[4].B.Patient-CentricHealthInformationSystemOtherresearcherspostulatedtheconceptofapatient-centricsystem.ThepatientistheownerofthehealthAchievingConfidentialityinElectronicHealthRecordsusingCloudSystems19Copyright©2018MECSI.J.ComputerNetworkandInformationSecurity,2018,1,18-25information,thereforemaintainsandmanagesacopyofhis/hermedicalrecords[5].TheIndivohealthinformationsystemisanexampleofapatient-centricsystem[6].C.SmartCardTheuseofelectronicsmartcardsasamechanismtoguaranteesecuritydata,andtoensureprivacyandconfidentialityinEHRshavetheirownuniqueadvantages.Featuresofsmartcardssuchas;portabilityandmobilityoftheelectronicsmartcardsareadvantagesthatwasharnessedtoprovideaccesssecurityinanelectronicpatienthealthrecordsystem[7].Smartcardsamongwasusedtostoresensitivepatienthealthdataandtoensuredataprivacyanddatasecurityinanelectronichealthinformationsystem.However,duetofrequentmisplacingofsmartcardsanduseofpinnumberstoaccesshealthinformationonsmartcardsmadeinunreliablemeans.D.Attribute-BasedEncryptionsFuzzyIdentity-BasedEncryptionIdentity–BasedEncryption(IBE)accesscontrolpolicycalledFuzzyIdentityBasedEncryptionwasdevelopedtoaddressprivacyandsecurityproblems