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Data Encryption
Simplifying Security.
Module 4
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Roughly40percentofITworkersbelievetheycouldholdanemployersnetworkhostage evenafterleavingthecompany bywithholdingorhidingencryptionkeys,accordingtoarecentsurveyof500ITsecurityspecialists.
Thestudy,releasedMonday,May23,alsorevealedthatathirdofsurveyrespondentswereconfidentthattheirknowledgeandaccesstoencryptionkeysandcertificatescouldbringacompanytoahaltwithlittleeffort.ConductedinApril2011,thesurveywassanctionedbyVenafi,anetworkkeyandencryptionprovider.
40PercentofITWorkersCouldHoldEmployerNetworksHostage,SurveyFinds
Itsashamethatsomanypeoplehavebeensoldencryptionbutnotthemeansorknowledgetomanageit,saidJeffHudson,CEOofVenafi,inastatement.ITdepartmentsmusttrackwherethekeysareandmonitorandmanagewhohasaccesstothem....Itsnolongerrocketscience.Yetrecent,costlybreachesatSony,Epsilonandelsewherereinforcetheneedforbothmoreencryptionandeffectivemanagement.
http://www.govtech.com
May23,2011
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Module Objectives
CommonTerminologies
WhatIsEncryption?
ObjectivesofEncryption
TypesofEncryption
EncryptionStandards
Symmetricvs.AsymmetricEncryption
UsageofEncryption
DigitalCertificates
WorkingofDigitalCertificates
DigitalSignature
HowDigitalSignatureWorks?
CryptographyTools
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Module Flow
Encryption TypesofEncryptionEncryptionStandards
DigitalCertificates
DigitalSignature
CryptographyTools
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5
Cipher TextCiphertextisencryptedandunreadable untilitisdecryptedtoplaintextwithakey
Encryption KeyAnencryptionkeyisapieceofinformationthatisusedtoencrypt anddecrypt data
Common Terminologies
PlaintextPlaintextorcleartext isunencryptedreadabletext
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What Is Encryption?
Plaintext(Morpheus)Bob Alice
Encryptionistheprocessofconvertingdataintoaciphertextthatcannotbeunderstoodbytheunauthorizedpeople
Toreadanencryptedfile,youmusthaveaccess toasecretkeyorpasswordthatenablesyoutodecryptit
Encryptionisusedtoprotectsensitiveinformation duringtransmissionandstorage
EncryptedDATAisreceivedbyAlice
Alicereceivestheplaindataafterdecryption
EncryptedDATA(3*.,[email protected]!w9)
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DataIntegrity
Authentication
Nonrepudiation
Thereceiverofamessagecancheckwhetherthemessagewasmodifiedduringtransmission,eitheraccidentallyordeliberately
Thereceiverofamessagecanverifytheoriginofthemessage
Nootherusershouldbeabletosendamessagetotherecipientastheoriginalsender(dataoriginauthentication)
Thesenderofamessagecannotdeny thathe/shehassentthemessage
Objectives of Encryption
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Usage of EncryptionIthelpstosafelystoresensitiveinformationonacomputerorexternalstoragemedia
Encryptionisusedtoprotectusercredentials suchasusernameandpasswords
Encryptionprovidesassurance ofasendersidentity
Itisalsousedasaresourceforwebbasedinformationexchangetoprotectimportantinformation suchascreditcardnumbers
Encryptionprovidesasecuremedium foruserstoconnecttotheirfriendsoremployeesnetworkfromoutsideofthehomeoroffice
Itprovidesahigherleveloftrust whenreceivingfilesfromotherusersbyensuringthatthesourceandcontentsofthemessagearetrusted
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Module Flow
Encryption TypesofEncryptionEncryptionStandards
DigitalCertificates
DigitalSignature
CryptographyTools
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Types of EncryptionSymmetricEncryptionSymmetricencryption(secretkey,sharedkey,andprivatekey)usesthesamekeyforencryptionanddecryption
AsymmetricEncryptionAsymmetricencryption(publickey)usesdifferentencryptionkeysforencryptionanddecryption.Thesekeysareknownaspublicandprivatekeys
HashFunction
Hashfunction(messagedigestsoronewayencryption)usesnokeyforencryptionanddecryption
DearJohn,ThisismyA/Cnumber7974392830
DearJohn,ThisismyA/Cnumber7974392830
GuuihifhofnkbifkfnnfkNklclmlm#^*&(*)_(_
Encryption Decryption
Plaintext PlaintextCiphertext
SymmetricEncryption
AsymmetricEncryption
DearJohn,ThisismyA/Cnumber7974392830
DearJohn,ThisismyA/Cnumber7974392830
GuuihifhofnkbifkfnnfkNklclmlm#^*&(*)_(_
Plaintext Ciphertext Plaintext
Encryption Decryption
Hashfunction
Plaintext Ciphertext
Hashfunction
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Symmetric vs. Asymmetric Encryption
SymmetricEncryption AsymmetricEncryption
Symmetricencryptionusesonlyonekeyforbothencryptionanddecryption
Thekeycannotbeshared freely
Symmetricencryptionrequiresthatboththesenderandthereceiverknowthesecretkey
Usingsymmetricencryption,datacanbe encryptedfaster
Thisalgorithmislesscomplexandfaster
Symmetricencryptionensuresconfidentialityandintegrity
AsymmetricEncryptionusesapublickeyforencryptionandaprivatekey fordecryption
Inasymmetricencryption,thepublickeycanbefreelyshared,whicheliminatestheriskofcompromisingthesecretkey
TheencryptionprocessusingAsymmetricEncryptionisslowerandmorecomplex
Asymmetricencryptionensuresconfidentiality,integrity,authentication,andnonrepudiation
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Module Flow
Encryption TypesofEncryptionEncryptionStandards
DigitalCertificates
DigitalSignature
CryptographyTools
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Encryption Standards
DataEncryptionStandard(DES)
AdvancedEncryptionStandard(AES)
DataEncryptionStandard(DES)isthenameoftheFederalinformationProcessingStandard(FIPS)463,whichdescribesthedataencryptionalgorithm(DEA)
TheDEAisasymmetriccryptosystemoriginallydesignedforimplementationinhardware
DEAisalsousedforsingleuserencryption,suchastostorefilesonaharddiskinencryptedform
AdvancedEncryptionStandard(AES)isasymmetrickeyencryptionstandardadoptedbytheU.S.government
Ithasa128bit blocksize,withkeysizesof128,192and256bits,respectively,forAES128,AES192andAES256
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Module Flow
Encryption TypesofEncryptionEncryptionStandards
DigitalCertificates
DigitalSignature
CryptographyTools
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Digital Certificates
Detailsofownerspublickey
DigitalsignatureoftheCA(issuer)
Serialnumberofdigitalsignature
Ownersname
Expirationdateofpublickey
NameoftheCertificateAuthority(CA)whoissuedthedigitalcertificate
Adigitalcertificateisanelectroniccardthatprovidescredentialinformationwhileperformingonlinetransactions
Itactsasanelectroniccounterparttoadrivers license,passport,ormembershipcardandverifiestheidentityofallusersinvolvedinonlinetransactions
Adigitalcertificategenerallycontains:
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PrivateKey
PublicKey Validationofelectronicsignature Inquiresaboutpublickeycertificate
validitytovalidationauthority
DeterminedResult
PublicKeyCertificate
Messageinpublickeycertificatesignedwithdigitalsignature
User
PublicKeyCertificate
UpdatesInformation
UserAppliesforCertificate
RegistrationAuthority(RA)
RequestforIssuingCertificate
ValidationAuthority(VA)
CertificationAuthority(CA)
How Digital Certificates Work
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Module Flow
Encryption TypesofEncryptionEncryptionStandards
DigitalCertificates
DigitalSignature
CryptographyTools
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Digital SignatureDigitalsignatureimplementsasymmetriccryptographytosimulatethesecuritypropertiesofasignatureindigital,ratherthanwrittenform
Digitalsignatureschemesinvolvetwoencryptionkeys:aprivatekeyforsigningthemessageandapublickeyforverifyingsignatures
Digitalstandardsfollowtheopenstandards astheyarenottiedtoanindividualormanufacturer
Itisoftenusedtoimplementelectronicsignatures andcanbeusedbyanytypeofmessage
Itisindependentofthesignature verificationbetweenthesenderandthereceiver
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How Digital Signature Works
SIGN
SEAL
DELIVER
ACCEPT
OPEN
VERIFY
Encryptmessageusingonetimesymmetrickey
EncryptthesymmetrickeyusingrecipientsPUBLICkey
Mailelectronicenvelopestotherecipient
ConfidentialInformation
Rehash the message and compare it with the hash value attached with the mail
RecipientdecryptonetimesymmetrickeyusinghisP
