SlideShare une entreprise Scribd logo
1  sur  36
Network Security Lecture 5
Public Key Cryptography and messae authentication ,[object Object],[object Object],[object Object]
Information Integrity Problems ,[object Object],Insert new record for Darth’s salary of $1,000,000 Salary Database E D E
Information Integrity Problems ,[object Object],Masquerading as Alice “ Give Darth a $10,000 raise -- Alice” E
Information Integrity Problems ,[object Object],“ Open the front gate. -- Alice” E
Information Integrity Problems ,[object Object],[object Object],[object Object],[object Object],Public storage M M ´
Information Integrity Problems ,[object Object],[object Object],[object Object],Public storage M M
Message Digest  ,[object Object],[object Object],[object Object],[object Object],[object Object]
Message Digest ,[object Object],[object Object],[object Object],[object Object],[object Object],Message Error detection bits
Modification Detection Code: MDC ,[object Object],[object Object],[object Object],[object Object],[object Object],Public storage M ´ h( M ´ ) h compare h( M )
Message Authentication Code:MAC ,[object Object],[object Object],[object Object]
Message Authentication Code ,[object Object],[object Object],[object Object]
Solving Integrity Problems ,[object Object],[object Object],[object Object]
Preimage Attack ,[object Object],[object Object],Public storage M ´ h( M ´ ) h Same! h( M )
Preimage Attack ,[object Object],[object Object],“ I’ll find some combination of these so they can’t detect the difference!”
Collision Attack ,[object Object],[object Object],[object Object]
Collision Attack ,[object Object],[object Object],[object Object],[object Object],[object Object],“We like kittens” h( “We like kittens” ) “ Give Darth a $5000 raise”
Digests and Networks ,[object Object],[object Object],[object Object],[object Object],M  
Digests and Networks ,[object Object],[object Object],M   h( M    )
Message Authentication Codes ,[object Object],[object Object],[object Object]
Message Authentication Codes ,[object Object],[object Object],[object Object],[object Object],M h ( M ,  k ) h ( M ,  k ) M h k h ( M ,  k ) compare “ If they match, then sender must have same key  k  as I do”
Authentication and Confidentiality ,[object Object],[object Object],[object Object],[object Object],h h h h h h h
Prefix/Postfix MAC ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Message
Nested MAC ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Chained MAC (CMAC) ,[object Object],[object Object]
Chained MAC (CMAC) ,[object Object],[object Object],[object Object],[object Object],[object Object]
Chained MAC (CMAC) ,[object Object],[object Object],[object Object],[object Object]
Chained MAC (CMAC) ,[object Object],[object Object],[object Object],[object Object]
Chained MAC (CMAC) ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Compression Functions ,[object Object],[object Object],[object Object],[object Object],[object Object],f Message of arbitrary size m -bit digest
Compression Functions ,[object Object],[object Object],f k -bit message m -bit digest
Iterated Hash Function Merkle-Damgard scheme If the compression function in Merkle-Damgard scheme is collision resistant, the Hash function is also collision resistant
Iterated Hash Function ,[object Object],[object Object],[object Object],[object Object],[object Object],f n -bit message block  M  i   m -bit digest  H  i m -bit digest  H  i-1
Types of Hash Algorithms ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Block Ciphers for Hashing  ,[object Object],[object Object],[object Object],[object Object],[object Object]
Block Ciphers for Hashing  ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Contenu connexe

Tendances

Cryptography and Message Authentication NS3
Cryptography and Message Authentication NS3Cryptography and Message Authentication NS3
Cryptography and Message Authentication NS3
koolkampus
 

Tendances (20)

Hash& mac algorithms
Hash& mac algorithmsHash& mac algorithms
Hash& mac algorithms
 
HMAC authentication
HMAC authenticationHMAC authentication
HMAC authentication
 
Cryptography and Message Authentication NS3
Cryptography and Message Authentication NS3Cryptography and Message Authentication NS3
Cryptography and Message Authentication NS3
 
Message digest 5
Message digest 5Message digest 5
Message digest 5
 
Lecture 2 Message Authentication
Lecture 2   Message AuthenticationLecture 2   Message Authentication
Lecture 2 Message Authentication
 
Message integrity protocol
Message integrity protocolMessage integrity protocol
Message integrity protocol
 
Message Authentication
Message AuthenticationMessage Authentication
Message Authentication
 
HMAC - HASH FUNCTION AND DIGITAL SIGNATURES
HMAC  - HASH FUNCTION AND DIGITAL SIGNATURESHMAC  - HASH FUNCTION AND DIGITAL SIGNATURES
HMAC - HASH FUNCTION AND DIGITAL SIGNATURES
 
Message AUthentication Code
Message AUthentication CodeMessage AUthentication Code
Message AUthentication Code
 
Network Security(MD5)
Network Security(MD5)Network Security(MD5)
Network Security(MD5)
 
Ch11
Ch11Ch11
Ch11
 
Public key cryptography and message authentication
Public key cryptography and message authenticationPublic key cryptography and message authentication
Public key cryptography and message authentication
 
Lecture 3b public key_encryption
Lecture 3b public key_encryptionLecture 3b public key_encryption
Lecture 3b public key_encryption
 
MAC-Message Authentication Codes
MAC-Message Authentication CodesMAC-Message Authentication Codes
MAC-Message Authentication Codes
 
Cryptographic hash function md5
Cryptographic hash function md5Cryptographic hash function md5
Cryptographic hash function md5
 
Distribution of public keys and hmac
Distribution of public keys and hmacDistribution of public keys and hmac
Distribution of public keys and hmac
 
6.hash mac
6.hash mac6.hash mac
6.hash mac
 
Hash Function
Hash FunctionHash Function
Hash Function
 
Message authentication and hash function
Message authentication and hash functionMessage authentication and hash function
Message authentication and hash function
 
MD5
MD5MD5
MD5
 

En vedette (13)

Network security
Network securityNetwork security
Network security
 
Network security at_osi_layers
Network security at_osi_layersNetwork security at_osi_layers
Network security at_osi_layers
 
Problems at independence
Problems at independenceProblems at independence
Problems at independence
 
Key management
Key managementKey management
Key management
 
Project Management
Project ManagementProject Management
Project Management
 
Lecture 9 key distribution and user authentication
Lecture 9 key distribution and user authentication Lecture 9 key distribution and user authentication
Lecture 9 key distribution and user authentication
 
A Tutorial on Linear and Differential Cryptanalysis by Howard M. Heys
A Tutorial on Linear and Differential Cryptanalysis by Howard M. HeysA Tutorial on Linear and Differential Cryptanalysis by Howard M. Heys
A Tutorial on Linear and Differential Cryptanalysis by Howard M. Heys
 
applist
applistapplist
applist
 
key distribution in network security
key distribution in network securitykey distribution in network security
key distribution in network security
 
Data Network Security
Data Network SecurityData Network Security
Data Network Security
 
Network Security 1st Lecture
Network Security 1st LectureNetwork Security 1st Lecture
Network Security 1st Lecture
 
Network security
Network securityNetwork security
Network security
 
Block Ciphers Modes of Operation
Block Ciphers Modes of OperationBlock Ciphers Modes of Operation
Block Ciphers Modes of Operation
 

Similaire à Network Security Lec5

unit 4.pptx of hash function in cryptography
unit 4.pptx of hash function in cryptographyunit 4.pptx of hash function in cryptography
unit 4.pptx of hash function in cryptography
NithyasriA2
 
Cryptography and Network Security Principles and PracticeSeve.docx
Cryptography and Network Security Principles and PracticeSeve.docxCryptography and Network Security Principles and PracticeSeve.docx
Cryptography and Network Security Principles and PracticeSeve.docx
mydrynan
 
Hash Techniques in Cryptography
Hash Techniques in CryptographyHash Techniques in Cryptography
Hash Techniques in Cryptography
Basudev Saha
 

Similaire à Network Security Lec5 (20)

Cryptography and network_security
Cryptography and network_securityCryptography and network_security
Cryptography and network_security
 
NSC_Unit-III_final.ppt
NSC_Unit-III_final.pptNSC_Unit-III_final.ppt
NSC_Unit-III_final.ppt
 
ch11.ppt
ch11.pptch11.ppt
ch11.ppt
 
unit 4.pptx of hash function in cryptography
unit 4.pptx of hash function in cryptographyunit 4.pptx of hash function in cryptography
unit 4.pptx of hash function in cryptography
 
Cs8792 cns - unit iv
Cs8792   cns - unit ivCs8792   cns - unit iv
Cs8792 cns - unit iv
 
Cs8792 cns - unit iv
Cs8792   cns - unit ivCs8792   cns - unit iv
Cs8792 cns - unit iv
 
Unit 3
Unit 3Unit 3
Unit 3
 
Cryptography and Network Security Principles and PracticeSeve.docx
Cryptography and Network Security Principles and PracticeSeve.docxCryptography and Network Security Principles and PracticeSeve.docx
Cryptography and Network Security Principles and PracticeSeve.docx
 
Cryptography and netwrk securityunit 4
Cryptography and netwrk securityunit 4Cryptography and netwrk securityunit 4
Cryptography and netwrk securityunit 4
 
Unit 4
Unit 4Unit 4
Unit 4
 
Message Authentication and Hash Function.pdf
Message Authentication and Hash Function.pdfMessage Authentication and Hash Function.pdf
Message Authentication and Hash Function.pdf
 
Cns
CnsCns
Cns
 
A Modified approach for implementation of an efficient padding scheme in a di...
A Modified approach for implementation of an efficient padding scheme in a di...A Modified approach for implementation of an efficient padding scheme in a di...
A Modified approach for implementation of an efficient padding scheme in a di...
 
A Modified approach for implementation of an efficient padding scheme in a di...
A Modified approach for implementation of an efficient padding scheme in a di...A Modified approach for implementation of an efficient padding scheme in a di...
A Modified approach for implementation of an efficient padding scheme in a di...
 
Hash Techniques in Cryptography
Hash Techniques in CryptographyHash Techniques in Cryptography
Hash Techniques in Cryptography
 
27-SHA1.ppt
27-SHA1.ppt27-SHA1.ppt
27-SHA1.ppt
 
Cryptographic-Hash-Functions.ppt
Cryptographic-Hash-Functions.pptCryptographic-Hash-Functions.ppt
Cryptographic-Hash-Functions.ppt
 
Message Authentication Requirement-MAC
Message Authentication Requirement-MACMessage Authentication Requirement-MAC
Message Authentication Requirement-MAC
 
Hash crypto
Hash cryptoHash crypto
Hash crypto
 
Hash crypto
Hash cryptoHash crypto
Hash crypto
 

Plus de Federal Urdu University

Plus de Federal Urdu University (20)

Ntc internship report
Ntc internship reportNtc internship report
Ntc internship report
 
Network Security Lec4
Network Security Lec4Network Security Lec4
Network Security Lec4
 
Network Security
Network SecurityNetwork Security
Network Security
 
Unix
UnixUnix
Unix
 
Os Linux Documentation
Os Linux DocumentationOs Linux Documentation
Os Linux Documentation
 
Os Linux
Os LinuxOs Linux
Os Linux
 
Maria Managment Spectrum
Maria Managment SpectrumMaria Managment Spectrum
Maria Managment Spectrum
 
Zohaib Dfd
Zohaib DfdZohaib Dfd
Zohaib Dfd
 
Zeeshan Estimation
Zeeshan EstimationZeeshan Estimation
Zeeshan Estimation
 
Zahid Asd
Zahid AsdZahid Asd
Zahid Asd
 
Umar Erd
Umar ErdUmar Erd
Umar Erd
 
Sohrab Waterfall Vs Rad
Sohrab Waterfall Vs RadSohrab Waterfall Vs Rad
Sohrab Waterfall Vs Rad
 
Sidra Agile Software Process
Sidra Agile Software ProcessSidra Agile Software Process
Sidra Agile Software Process
 
Muzammil Prescriptive Vs Agile Process Models
Muzammil Prescriptive Vs Agile Process ModelsMuzammil Prescriptive Vs Agile Process Models
Muzammil Prescriptive Vs Agile Process Models
 
Muzammil Agile Vs Prescriptive
Muzammil Agile Vs PrescriptiveMuzammil Agile Vs Prescriptive
Muzammil Agile Vs Prescriptive
 
Khurram Spiral
Khurram SpiralKhurram Spiral
Khurram Spiral
 
Hira Xp
Hira XpHira Xp
Hira Xp
 
G4 Group
G4 GroupG4 Group
G4 Group
 
Faisal Incremental Model
Faisal Incremental ModelFaisal Incremental Model
Faisal Incremental Model
 
Ather Proactive Vs Reactive
Ather Proactive Vs ReactiveAther Proactive Vs Reactive
Ather Proactive Vs Reactive
 

Dernier

+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
?#DUbAI#??##{{(☎️+971_581248768%)**%*]'#abortion pills for sale in dubai@
 
Architecting Cloud Native Applications
Architecting Cloud Native ApplicationsArchitecting Cloud Native Applications
Architecting Cloud Native Applications
WSO2
 

Dernier (20)

+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
+971581248768>> SAFE AND ORIGINAL ABORTION PILLS FOR SALE IN DUBAI AND ABUDHA...
 
How to Troubleshoot Apps for the Modern Connected Worker
How to Troubleshoot Apps for the Modern Connected WorkerHow to Troubleshoot Apps for the Modern Connected Worker
How to Troubleshoot Apps for the Modern Connected Worker
 
"I see eyes in my soup": How Delivery Hero implemented the safety system for ...
"I see eyes in my soup": How Delivery Hero implemented the safety system for ..."I see eyes in my soup": How Delivery Hero implemented the safety system for ...
"I see eyes in my soup": How Delivery Hero implemented the safety system for ...
 
Apidays New York 2024 - The value of a flexible API Management solution for O...
Apidays New York 2024 - The value of a flexible API Management solution for O...Apidays New York 2024 - The value of a flexible API Management solution for O...
Apidays New York 2024 - The value of a flexible API Management solution for O...
 
Manulife - Insurer Transformation Award 2024
Manulife - Insurer Transformation Award 2024Manulife - Insurer Transformation Award 2024
Manulife - Insurer Transformation Award 2024
 
Emergent Methods: Multi-lingual narrative tracking in the news - real-time ex...
Emergent Methods: Multi-lingual narrative tracking in the news - real-time ex...Emergent Methods: Multi-lingual narrative tracking in the news - real-time ex...
Emergent Methods: Multi-lingual narrative tracking in the news - real-time ex...
 
Polkadot JAM Slides - Token2049 - By Dr. Gavin Wood
Polkadot JAM Slides - Token2049 - By Dr. Gavin WoodPolkadot JAM Slides - Token2049 - By Dr. Gavin Wood
Polkadot JAM Slides - Token2049 - By Dr. Gavin Wood
 
Architecting Cloud Native Applications
Architecting Cloud Native ApplicationsArchitecting Cloud Native Applications
Architecting Cloud Native Applications
 
ICT role in 21st century education and its challenges
ICT role in 21st century education and its challengesICT role in 21st century education and its challenges
ICT role in 21st century education and its challenges
 
Exploring Multimodal Embeddings with Milvus
Exploring Multimodal Embeddings with MilvusExploring Multimodal Embeddings with Milvus
Exploring Multimodal Embeddings with Milvus
 
2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...2024: Domino Containers - The Next Step. News from the Domino Container commu...
2024: Domino Containers - The Next Step. News from the Domino Container commu...
 
Apidays New York 2024 - The Good, the Bad and the Governed by David O'Neill, ...
Apidays New York 2024 - The Good, the Bad and the Governed by David O'Neill, ...Apidays New York 2024 - The Good, the Bad and the Governed by David O'Neill, ...
Apidays New York 2024 - The Good, the Bad and the Governed by David O'Neill, ...
 
Exploring the Future Potential of AI-Enabled Smartphone Processors
Exploring the Future Potential of AI-Enabled Smartphone ProcessorsExploring the Future Potential of AI-Enabled Smartphone Processors
Exploring the Future Potential of AI-Enabled Smartphone Processors
 
Connector Corner: Accelerate revenue generation using UiPath API-centric busi...
Connector Corner: Accelerate revenue generation using UiPath API-centric busi...Connector Corner: Accelerate revenue generation using UiPath API-centric busi...
Connector Corner: Accelerate revenue generation using UiPath API-centric busi...
 
Apidays New York 2024 - APIs in 2030: The Risk of Technological Sleepwalk by ...
Apidays New York 2024 - APIs in 2030: The Risk of Technological Sleepwalk by ...Apidays New York 2024 - APIs in 2030: The Risk of Technological Sleepwalk by ...
Apidays New York 2024 - APIs in 2030: The Risk of Technological Sleepwalk by ...
 
AWS Community Day CPH - Three problems of Terraform
AWS Community Day CPH - Three problems of TerraformAWS Community Day CPH - Three problems of Terraform
AWS Community Day CPH - Three problems of Terraform
 
Repurposing LNG terminals for Hydrogen Ammonia: Feasibility and Cost Saving
Repurposing LNG terminals for Hydrogen Ammonia: Feasibility and Cost SavingRepurposing LNG terminals for Hydrogen Ammonia: Feasibility and Cost Saving
Repurposing LNG terminals for Hydrogen Ammonia: Feasibility and Cost Saving
 
FWD Group - Insurer Innovation Award 2024
FWD Group - Insurer Innovation Award 2024FWD Group - Insurer Innovation Award 2024
FWD Group - Insurer Innovation Award 2024
 
CNIC Information System with Pakdata Cf In Pakistan
CNIC Information System with Pakdata Cf In PakistanCNIC Information System with Pakdata Cf In Pakistan
CNIC Information System with Pakdata Cf In Pakistan
 
Boost Fertility New Invention Ups Success Rates.pdf
Boost Fertility New Invention Ups Success Rates.pdfBoost Fertility New Invention Ups Success Rates.pdf
Boost Fertility New Invention Ups Success Rates.pdf
 

Network Security Lec5

  • 2.
  • 3.
  • 4.
  • 5.
  • 6.
  • 7.
  • 8.
  • 9.
  • 10.
  • 11.
  • 12.
  • 13.
  • 14.
  • 15.
  • 16.
  • 17.
  • 18.
  • 19.
  • 20.
  • 21.
  • 22.
  • 23.
  • 24.
  • 25.
  • 26.
  • 27.
  • 28.
  • 29.
  • 30.
  • 31.
  • 32. Iterated Hash Function Merkle-Damgard scheme If the compression function in Merkle-Damgard scheme is collision resistant, the Hash function is also collision resistant
  • 33.
  • 34.
  • 35.
  • 36.