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WGU C839 Objective Assessment Study Guide (Latest 2024/ 2025 Update) Introduction to Cryptography| Qs & As| Grade A| 100% Correct (Verified Answers) $10.99   Add to cart
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WGU C839 Objective Assessment Study Guide (Latest 2024/ 2025 Update) Introduction to Cryptography| Qs & As| Grade A| 100% Correct (Verified Answers)
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WGU C839 Objective Assessment Study Guide (Latest 2024/ 2025 Update) Introduction to Cryptography| Qs & As| Grade A| 100% Correct (Verified Answers) Q: Information Theory Answer: -Published by Claude Shannon in 1949 in the Bell System Technical Journal - Important concepts: -Diffusion ...

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  • October 13, 2024
  • 66
  • 2024/2025
  • Exam (elaborations)
  • Questions & answers

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  • serp
  • wgu c839c839 introduction to cryptographyc839 oa
  • c839wgu c839 introduction to cryptographyc839 pa
  • c839c839 introduction to cryptographywgu c839 oa
  • wgu c839 objective assessment study guide latest

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WGUIC839IObjectiveIAssessmentIStudyI
GuideI(LatestI2024/I2025IUpdate)I
IntroductionItoICryptography|IQsI&IAs|I
GradeIA|I100%ICorrectI(VerifiedIAnswers)

Q:IInformationITheory
Answer:
-PublishedIbyIClaudeIShannonIinI1949IinItheIBellISystemITechnicalIJournal
-IImportantIconcepts:
I-Diffusion
I-Confusion
I-AvalancheIEffectI(HorstIFeist'sIvariationIonIShannon'sIconceptIofIdiffusion

Q:IKerckhoff'sIPrinciple
Answer:
-1883
-
AIcrptosystemIshouldIbeIsecureIevenIifIallIitsIelementsIofItheIsystem,IexceptItheIkey,IisIpubli
cIknowledge

Q:IFeistelINetwork
Answer:
-AIcryptographicIprimitiveIthatIformsItheIbasisIofImanyIsymmetricIalgorithms.I
-
FeistelInetworksIcombineImultipleIroundsIofIrepeatedIoperations,IsuchIasIprocessingIcleartextI
inputIwithIXORIfunctions.I
-AIkeyIscheduleIisIusedItoIproduceIdifferentIkeysIforIeachIround.
-StartsIbyIsplittingIplaintextIdataIintoItwoIparts
I-L0IandIR0
-UsuallyIsplitIequallyIbutInotIalways
-UnbalancedIFeistelICipherIusesIaIsplitIthatIisIunequal
-TheI"roundIfunction"IFIisIappliedItoIoneIofItheIhalfs

,-
TheItermIroundIfunctionIrefersItoIaIfunctionIperformedIwithIeachIiterationIofItheIfeistalIcipher
-TheIoutputIofIeachIroundIfunctionIFIisIthenIXORedIwithItheIotherIhalf
-
TheImainIdifferenceIbetweenIcryptographyIalgorithmsIisItheIexactInatureIofItheIroundIfunctio
nIF,IandItheInumberIofIiterations

Q:IDataIEncryptionIStandardI(DES)
Answer:
-64IbitIalgorithm
-OperatingIatI56-bits
-8IbitIparityIblocks
-SymmetricIKeyIAlgorithm

Q:IDataIEncryptionIStandardI(DES)IOperation
Answer:
-I1.IDataIisIdividedIintoI64IbitIblocks
-2.IThatIdataIisIthenImanipulatedIbyI16IseparateIstepsIofIencryptionIinvolving:
I-Substitutions
I-Bit-Shifting
I-LogicalIoperations
I-UsingIaI56IbitIkey
-I3.IDataIisIthenIfurtherIscrambledIbyIusingIaIswappingIalgorithm
-I4.IDataIisIfinallyItransposedIoneIlastItime
-NSAITypeI3Ialgorithm

Q:IDESIS-Boxes
Answer:
-IDESIusesI8I"S-boxes"
-S-BoxesIareISubstitutionIBoxes
-S-BoxesIareIbasicallyIlookupItables
-EachIS-BoxIhasIaItableIthatIdeterminesI(basedIonItheIbitsIpassedItoIit)
I-WhatItoIsubstituteIforIthoseIbitsIfor
-EachIitemIpassedIintoItheIboxIisIsubstitutedIwithItheIitemIthatImatchesIitIinItheIlookupItable
-EachIoneIofItheIDESIS-boxesItakesI6IbitsIandIproducesI4Ibits
-TheImiddleI4IbitsIofItheI6IbitIinputsIareIusedItoIlookupItheI4IbitIreplacementIbits

Q:I3DESI(TripleIDES)

,Answer:
-ISymmetricIKeyIAlgorithm
-TypeI3IAlgorithmI(NSA)
-IAppliesIDESIthreeItimes
-I168-bitIkeyI(+24IforIparity)
-IUsesIaI"keyIbundle"
-KeyIbundleIhasI3IDESIkeys
I-k1
I-k2
I-k3
-EachIkeyIisIstandardI56-bitIkey
-DESIencryptsIwithIk1
-DecryptsIwithIk2
-ThenIencryptsIagainIwithIk3

Q:IDESx
Answer:
-SymmetricIalgorithm.I
-64IbitIkeyIisIappendedItoIdata,IXORIit,IandIthenIapplyItheIDESIalgorithm.
-
VariationIofIDESIthatIXORsIanotherI64IbitIkeyItoItheIplaintextIbeforeIapplyingItheIDESIalgor
ithm
-IUsesIWhitening
-AddItoItheIconfusionIofItheIresultantItext

Q:IWhitening
Answer:
-TheIconceptIofIsimplyIXORingIinIanIadditionalIkeyItoIaddIconfusion

Q:IAdvancedIEncryptionIStandardI(AES)
Answer:
-IAIsymmetricIcipher
-Rijndael
-ReplacedIDESIasIofI2001
-IthatIwasIapprovedIbyItheINISTIinIlateI2000IasIaIreplacementIforIDES.
-FormallyIannouncedIbyINISTIasIFIPSI197
-UsedIaIsubstitution-permutationImatrix
I-InsteadIofIaIFeistelInetwork

, -OperatesIonIaI4x4IcolumnImajorIorderImatrixIofIbytes
I-CalledIstates

Q:IAdvancedIEncryptionIStandardI(AES)-KeyIsizesIandIblockIsize
Answer:
-AES128I(128-bits,I128IbitIblockIsize)
-AES192I(192-bits,I128IbitIblockIsize)
-AES256I(256-bits,I128IbitIblockIsize)

Q:IAdvancedIEncryptionIStandardI(AES)-Operation
Answer:
-1.IKeyIexpansion
I-RoundIkeysIareIderivedIfromItheIcipherIkeyIusingIRijndael'sIkeyIschedule
-2.IInitialIround:
I-AddRoundKey
I-EachIbyteIofItheIstateIisIcombinedIwithItheIroundIkeyIusingIbitwiseIXOR
-3.IRoundsI
I-SubBytes
I-
AInonIlinearIsubstitutionIstepIwhereIeachIbyteIisIreplacedIwithIanotherIaccordingItoIaIlookupI
table
I-LookupItableIisIcalledIaIRijndaelIS-Box
I-ShiftRows
I-
AItranspositionIstepIwhereIeachIrowIofItheIstateIisIshiftedIcyclicallyIaIcertainInumberIofIsteps
I-MixColums
I-
AImixingIoperationIwhichIoperatesIonItheIcolumnsIofItheIstate,IcombiningItheIfourIbytesIinIe
achIcolumn
I-AddRoundKey
4.IFinalIRoundI(noIMixColumnsIused):
I-SubBytes
I-ShiftRows
I-AddRoundKey

Q:IBlowfish
Answer:
-ISymmetricIcipher
-FeistelICipher

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