Describe the purpose of the process outline on slide 9   on the attached document.Please describe it about 100-150 words

 

 

Cryptography
Week 6 © Copyright 2012 – 2013 (ISC)², Inc. All Rights Reserved. For Personal Use of (ISC)2 Seminar Attendee Only.
Contents May Not Be Copied or Otherwise Distributed Under Any Circumstances Message Integrity Controls
(MIC) © Copyright 2012 – 2013 (ISC)², Inc. All Rights Reserved. For Personal Use of (ISC)2 Seminar Attendee Only.
Contents May Not Be Copied or Otherwise Distributed Under Any Circumstances Categories of
Cryptosystems
Organizatio
n of
Cryptosyste
ms Two-Way
Cryptograp
hy Symmetric Stream Steganogra
phy Message
Integrity
Controls Asymmetric Block Factoring
the Product
of Large
Primes Discreet
Logarithms Page 369
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Reserved. For Personal Use of (ISC)2 Seminar Attendee Only. Message Integrity Controls (MIC) • MICs detect
Accidental Change
alterations
(whether
intentional or
accidental) to a
message during
transmission
HMAC
CBC-MAC
• A MIC is a special
Digital
value that is
Signature
calculated based
on the message Intentional Change
contents and
Page 370
added to the ©©Copyright
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Reserved. For Personal Use of (ISC)2 Seminar Attendee Only. Hash Function
Characteristics
• Produces a “condensed representation” of
the original message
• Should be a one-way function
• Non-linear relationship between hashes
• Should derive the hash using the whole,
original message Page 371
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Reserved. For Personal Use of (ISC)2 Seminar Attendee Only. Common Hash Functions
• Message Digest 2, 4, 5, 6
• Secure Hash Algorithm (SHA) 1, 2, 3
• HAVAL
• RIPEMD
• Tiger
• WHIRLPOOL Page 372
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Reserved. For Personal Use of (ISC)2 Seminar Attendee Only. Digital Signatures
• What are digital signatures?
Bob Alice
Message Message Message Digital
Signature Digital
Signature Message Hash Hash
E Digest ©©Copyright
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Reserved. Alice’s
Private Key D Digest Digest
Verified Page 373 For Personal Use of (ISC)2 Seminar Attendee Only. Uses of Digital
Signatures
• E-commerce
• Non-repudiation of origin
• Integrity of message
• Software distribution
• Trusted time stamp Page 374
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Reserved. For Personal Use of (ISC)2 Seminar Attendee Only. Example of a Complex Hybrid
System
Alice Bob’s Public Key E CT(k) D E D Messag
e H Alice’s
Private Key Diges
t
Diges
t D Bob’s
Public
Key
©©Copyright
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Reserved. Bob Bob’s Private Key H Alice’s
Public Key E D Diges
t Diges
t Digital
Signature Messag
e Diges
t
E
Bob’s
Private
Key
For Personal Use of (ISC)
Seminar Attendee Only.
2 This week
• Read/review/memorize the cryptography
flash cards.
• Homework: Describe the purpose of the
process outline on slide 9 (the previous
slide) ©©Copyright
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Reserved. For Personal Use of (ISC)2 Seminar Attendee Only.