CSCI 284/Spring 2009/Vora/GWU/Homework 6/assigned: 15 April 2009/due: 29 April 2009
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CSCI 284 - Cryptography - Spring 2009 George Washington University Homework 6: due 29 April, 2009 Policy on collab
CSCI 124 Discrete Structures II: Groups Denition and Examples
Poorvi L. Vora
In this module, we attempt to look at the similarities between the afne and shift ciphers using the notion of a group
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A G
CSCI 124/Vora/GWU
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CSCI 124: Discrete Structures II: Modular Arithmetic
Poorvi L. Vora We start with three simple examples from cryptography to illustrate the need for the mathematics of what is know
Block Ciphers
CSCI 284/162 Spring 2009 GWU
Some of this slide set is from Section 2, H. M. Heys, "A Tutorial on Linear and Differential Cryptanalysis", Technical Report CORR 2001-17, Centre for Applie
- Linear Cryptanalysis - Differential Cryptanalysis
Cryptanalysis of Block Ciphers
CSCI284 Spring 2009 GWU
This slide set almost entirely from: H. M. Heys, "A Tutorial on Linear and Differential Crypt
Efficient Exponentiation
CSCI284 Spring 2009 GWU
Efficient exponentiation (from Memon notes)
Usual approach to computing xc mod n is inefficient when c is large. Example: 551 involves 50 multiplicatio
GCD
CSCI 284/162 Spring 2009 GW
Zm
Definition: a b (mod m) m divides a-b Zm is the "ring" of integers modulo m: 0, 1, 2, .m-1 with normal addition and multiplication, performed modulo m We define a mo