CS/ECE/Math 435, Introduction to Cryptography  Spring 2015
Nigel Boston
Contact Information
3619 Engineering Hall, 303 Van Vleck
Telephone: 2653817, 2634753.
Email: boston@math.wisc.edu
Homepage
Office Hours: M 34:30 (303 VV) and W 1:303 (3619 EH); or by appointment.
Text
Eric Bach's course notes can be picked up at Bob's Copy Shop.
Interesting Links
Famous Unsolved Codes and Ciphers
Comic courtesy of Bill Kay
Diaconis article
Stick figure guide to AES, courtesy of John Cabaj
Vigenere cipher used by Confederacy
Magician card trick of Fitch Cheney
Article on factoring of RSA129
Twenty years of attacks on the RSA cryptosystem
Course objectives
Familiarity with the major algorithms of historical and
modern cryptography as documented in open literature;
knowledge of issues involved in choice of algorithm and
key size; ability to analyze performance of various cryptographic and cryptanalytic algorithms
Topics covered

Classical cryptography: substitution ciphers, polyalphabetic
methods, etc.

Introduction to cryptanalysis: frequency counts, coincidence
index, Shannon's theory

Block ciphers (DES, IDEA, AES, etc.)

Publickey cryptography (modular arithmetic, systems based
on factoring and discrete logarithms)

Cryptographic protocols (key exchange methods, digital
signatures, secret sharing, authentication)
Sections
 Main Lecture: MWF, 11:0011:50, 1227 Engineering Hall.
Grading Policy
The HW will be worth 10%, each midterm 20%, and the final 50% of your grade.
If you score 90% or higher, you will get an A; if you score 80% or higher, you will at least get a B;
if you score 70% or higher, you will at least get a C; if you score 60% or higher, you will at least
get a D.
Homework Assignments
Homework will be set most Fridays and due the following Friday. You are encouraged to discuss
the exercises with your classmates but the work you hand in should be your own.
The following tables may be of help to you:
 Addition and Multiplication mod 26
 Helpful Statistical Information for Cryptograms
 1st Homework, due Feb 6.
 2nd Homework, due Feb 13.
 3rd Homework, due Feb 20.
 4th Homework, due Feb 27.
 5th Homework, due Mar 13.
 6th Homework, due Mar 20.
 7th Homework, due Mar 27.
 8th Homework, due Apr 17.
 9th Homework, due May 1.
 10th Homework, due May 8.
Midterms
Friday, March 6, and Friday, April 24, at 11:00am in 1800 EH
 Practice 1st Midterm, no.1
 Practice 1st Midterm, no.2
 Practice 1st Midterm, no.3
 Practice 2nd Midterm, no.1
 Practice 2nd Midterm, no.2
 Practice 2nd Midterm, no.3
Final