CS651 Fall 2007: Principles of Cryptography

Summary | Topics | Reading | Grading


The modern study of cryptography investigates techniques for facilitating interactions between distrustful entities. In our connected society, such techniques have become indispensable--- enabling, for instance, automated teller machines, secure wireless networks, internet banking, satellite radio/television and more. In this course we introduce some of the fundamental concepts of this study. Emphasis will be placed on rigorous proofs of security based on precise definitions and assumptions.

Topics include: one-way functions, encryption, signatures, pseudo-random number generation, zero-knowledge and basic protocols.

Note: This will be a theory course. You will be expected to read and write formal definitions and mathematical proofs. This is not a course in security: you will not learn how to secure your system. Cryptography is only one (important) part of security. We will not study cryptographic acronyms or all cryptographic protocols in use today. Rather we focus on some of the fundamental design paradigms and on notions that will allow you to critically evaluate cryptographic protocols.

Topics Outline (Subject to Change)

Suggested Reading

Lecture notes will be made available; but should not serve as a substitute for the lectures. In particular, lecture notes might sometimes be posted after the class.

There is no required text for the course other than the lecture notes. You may find the following two books to be useful references. Note, however, that we will not always be following the same notational conventions as these books.

For a more applied treatment of cryptography, I suggest the following book which is available on-line.

For background reading on probability, algorithms, and complexity theory, I recommend:


There will be 5 homeworks, a mid-term and a final exam. The midterm is in class on Oct 10. Weights: homeworks 60%, mid-term 15% and final 25%.

Homework Policy

You are free to collaborate with other students on the homework, but you must turn in your own individually written solution and you must specify the names of your collaborators. Additionally, you may make use of published material, provided that you acknowledge all sources used. Note that it is a violation of this policy to submit a problem solution that you are unable to explain orally to a member of the course staff.

Assignments will be posted on this website. Typed problem sets are strongly preferred. I recommend that you learn and use LaTeX. Homework need to be handed in before the beginning of class. Additionally, you have a total of 4 "late-days" that you can use throughout the semester.