COMS BC3262: Introduction to Cryptography

Spring 2026
Barnard College

Course Details

Instructor: Prof. Eysa Lee

TA: Mark Chen [email protected]

Lectures: Mon/Wed 1:10pm-2:25pm, 202 Milbank Hall

Office Hours:

Course Links

Class Discussion Forum: EdStem (login required)

Courseworks: Link

Syllabus: Link

Lecture Schedule

The schedule below will be updated as the course progresses.

Week Date Topic Optional Readings Assignment
1 1/21 1 - Introduction
[Slides]
Ch 1.1-1.3 [Pass shelat]

Extra Resources:
Basic Analytical Reasoning & Notation for non-Math majors and A crash course in probability by Periklis A. Papakonstantinou
2 1/26 2 - Perfect Secrecy and Computational Security
[Slides]
Ch 2, 3.1-3.2 [Katz Lindell] PS1 Released [Link] [Template]
1/28 3 - Pseudorandom Generators and Reductions
[Slides]
Ch 3.2-3.3 [Katz Lindell]
3 2/02 4 - CPA-Security, Pseudorandom Functions, and PRFs from PRGs
[Slides]
Ch 3.4-3.5 [Katz Lindell]
2/04 5 - CPA-Security Encryption using PRFs, PRPs, and Block Ciphers
[Slides]
Ch 3.5.1-3.5.2, 7.2.3-7.2.5 [Katz Lindell]
Ch 3.1.1 [Pass shelat]
PS2 Released [Link] [Template]
PS1 Due Thursday, 2/5
4 2/09 6 - Review and Modes of Operation
[Slides]

(Note: Though OWFs were included in these slides, introduction of OWFs has been moved to a later lecture.)

3.6.3 [Katz Lindell]
2/11 7 - Review and OWFs

(There are no new slides for this lecture.)

Extra Resource:
Example Proof by Ran Cohen
5 2/16 8 - OWFs and MACs
[Slides]
4.1-4.4, 8.1 [Katz Lindell]
2/18 9 - CCA-Security
[Slides]
5.1-5.3 [Katz Lindell] PS3 Released [Link] [Template]
PS2 Due Thursday, 2/19
6 2/23 10 - CRHF [Slides]

(Remote - Snow Day)

6.1-6.3.1, 6.4-6.4.1, 6.6.1 [Katz Lindell]
2/25 11 - CRHF [Slides]

(Midterm will not cover any material introduced past this point.)

6.3.1, 6.5 [Katz Lindell]
7 3/02 12 - Number Theory [Slides] 9-9.1.4 [Katz Lindell]
3/04 13 - Secret Sharing [Slides] 3 [Rosulek], 6.1 [Pass shelat] PS3 Due Thursday, 3/05
8 3/09 Midterm Review

(There are no new slides for this lecture.)

3/11 Midterm
- Spring Recess
9 3/23 14 - Midterm Recap [Slides]

(Note: Introduction of cyclic groups have been moved to Lecture 15.)

3/25 15 - Discrete Log, CDH, DDH [Slides] 9.3.1-9.3.2, 9.4.2 [Katz Lindell]
10 3/30 16 - Key Exchange and Public Key Encryption [Slides] 11.3 [Katz Lindell]
4/01 17 - El-Gamal and Factoring [Slides] 12.1 - 12.2, 12.4 [Katz Lindell] PS 4 Released [Link] [Template]
11 4/06 18 - RSA [Slides] 9.2 [Katz Lindell]
4/08 19 - Signatures and RSA-FDH [Slides] 13.1-13.4 [Katz Lindell]
12 4/13 20 - Identity Schemes and Schnorr Signatures [Slides] 13.5 [Katz Lindell]
4/15 21 - Zero-Knowledge Proofs and Lamport Signatures [Slides] PS 5 Released [Link]
PS 4 Due Thursday, 4/16
13 4/20 Special Topic: Quantum Cryptography
(Guest Lecture by Barak Nehoran)

(Concepts covered in this lecture may appear as extra credit on the final exam.)

4/22 Special Topic: Post-Quantum Cryptography
(Guest Lecture by Rachit Garg)

(Concepts covered in this lecture may appear as extra credit on the final exam.)

14 4/27
4/29 PS 5 Due Thursday, 4/30
15 5/04
- 5/11 Final Exam
Time: 1:10pm-4pm
Location: Milstein 307