Download Chapter 10 Outline

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Chapter 10 Outline
This document is an attempt to describe how the contents of chapter 10 will be
covered in class. Not all of chapter 10 will be covered while some things will be covered
in greater depth in class than in the book. Also, things will not be covered in the same
order as in the book. Even though the book and the lectures don’t match completely, the
assumption is that you will read what the book has to say. I have also prepared files
which include the stuff I will cover in class. The ultimate measure of “what you have to
know” comes from the assignments. Your level of understanding of the material,
whether gleaned from reading the book or the files, should allow you to answer the type
of questions and problems that appear in the assignment files.
Stage 1
Lectures will be on: cs413securitynotes.doc. The title of this document is “Key Based
Computer Cryptosystems: Just Enough Background to Believe that They’re Not Black
Magic”. This document will be presented as overheads. (This note is for my reference:
These overheads are not numbered.)
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This provides a review of some of the concepts of chapters 1 and 2 and uses
concrete examples to put symmetric (secret key) and asymmetric (public key)
encryption in context.
It explains the ideas behind DES/AES style encryption. This corresponds to
section 10.2 in the book, “Symmetric Encryption”.
It illustrates asymmetric encryption using Merkle Hellman knapsacks. This
corresponds to the first part of section 10.3 in the book, “Public Key Encryption
Systems”. The treatment given here does not fully explain the math. It does not
prove that you can invert in a modular field, or give an algorithm for finding an
inverse if one exists.
These related documents will also be posted:
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cs413secretkey.doc. The title of this document is “Confusion and Diffusion in
Secret Key (Symmetric) Encryption”. It gives a more complete treatment of the
material on DES/AES found in cs413securitynotes.doc. (This note is for my
reference: As overheads these pages are numbered 132-139.)
cs413merklehellman.doc. The title of this document is “The Knapsack Problem
and Merkle Hellman Encryption”. It gives a more complete treatment of the
material on Merkle Hellman encryption found in cs413securitynotes.doc. (This
note is for my reference: As overheads these pages are numbered 169-173.)
It will probably be desirable to work a few Merkle Hellman problems in class in
preparation for the assignment.
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Assignment 3 will cover these topics, including general questions on Merkle Hellman
knapsacks, which do not require knowledge of inversion.
Stage 2
Lectures will be on the subject of NP completeness. This corresponds to the first part of
section 10.1 in the book, “Mathematics for Cryptography”. There is no electronic
document and there are no overheads. (This note is for my reference: In my paper notes
these pages are numbered 140-146.)
There is no assignment for this stage.
Stage 3
Lectures will be on: cs413encryptmath.doc. The title of this document is “Math for
Encryption”. This document will be presented as overheads. (This note is for my
reference: As overheads these pages are numbered 147-158.)
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This corresponds to the first part of the second half of section 10.1 in the book,
“Mathematics for Cryptography”.
It serves as a starting point for discussing the math involved in public key
encryption schemes like Merkle Hellman knapsacks and RSA encryption.
The treatment given in this document begins to be more in depth than in the book.
Stage 4
Lectures will be on: cs413proofsthms.doc. The title of this document is “Some Proofs
and Fermat’s Little Theorem”. This document will be presented as overheads. (This note
is for my reference: As overheads these pages are numbered 159-168.)
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This corresponds to the second part of the second half of section 10.1 in the book,
“Mathematics for Cryptography”.
It continues to go into greater depth than the book. As the title indicates, for
example, a demonstration of Fermat’s Little Theorem is given.
Although students won’t be responsible for reproducing demonstrations, for the
sake of understanding, an attempt is made to demonstrate the results from number
theory that are needed in order to show that advanced encryption schemes work.
This related document will be posted again:
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cs413merklehellman.doc. The title of this document is “The Knapsack Problem
and Merkle Hellman Encryption”. It gives a more complete treatment of the
material on Merkle Hellman encryption found in cs413securitynotes.doc. (This
note is for my reference: As overheads these pages are numbered 169-173.)
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It may again be desirable to work a few Merkle Hellman problems in class in preparation
for the assignment.
Assignment 4 will cover the general topic of math for encryption and Fermat’s Little
Theorem. It will also include Merkle Hellman encryption problems where it is necessary
to understand inversion.
Stage 5
Lectures will be on: cs413eulerrsa.doc. The title of this document is “Euler’s Theorem
and RSA Encryption”. This document will be presented as overheads. (This note is for
my reference: As overheads these pages are numbered 174-186.)
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This corresponds to the second part of section 10.3 in the book, “Public Key
Encryption Systems”.
This continues the pattern of going into depth, trying to explain fully the
mathematical basis for RSA encryption.
Your level of understanding of the material, whether gleaned from reading the
book or the file mentioned here, should allow you to answer the type of questions
and problems that appear in the assignment files. Demonstrations will not be
required.
Assignment 5 will cover RSA encryption.
Post Script
I will not be covering the third part of section 10.3 in the book, “El Gamal and Digital
Signature Algorithms”. I will also not be covering section 10.4 in the book, “Quantum
Cryptography”. If you are interested in these topics you may read what’s in the book and
see what you make of them. They will not be covered in the assignments or on the tests.