Main

CS 195-7: Introduction to Cryptography

Anna Lysyanskaya, TTh 1-2:30, CIT 506

NOTE: THERE WILL BE NO CLASS ON 9/24 AND 9/26 -- I WILL BE OUT OF TOWN.

In this course, we will address questions such as:

Can a secret message be sent over an insecure channel? How can Alice send a message to Bob such that Bob will understand it but no eavesdropper will?
Can we guarantee authenticity of data? How can Bob be sure that the message he received is indeed from Alice? How can he convince someone else of this fact?
Can we guarantee that it is impossible to cheat in an on-line game? Can Alice and Bob play cards over the Internet?

To answer these questions, we will first decide what security property are desirable for the situation at hand. We will then formally define the objects that we wish to derive: encryption schemes, signature schemes, secure protocols. Finally, we will give suitable constructions and prove that they satisfy the definition we have given.

This course is theoretical. If you are interested in computer security at large, keep in mind that cryptography is only a part of it. Secure systems require appropriate architecture, operating system, secure hardware -- all these things are beyond the scope of this course and we will take them largely for granted.

Most of the work in this class will be on solving problems: constructing cryptosystems and proving them secure, relating notions of security, etc. You can collaborate on all homework assignments. There will also be a midterm and a final exam.

You can earn 200-level credit by doing a small research project instead of the final exam.