Announcements
- Spring 2026 lecture slides and course materials are available below.
Course Information
Time/location
- Monday and Wednesday, 11:35am–12:50pm
- WTS A46, Watson Center, 60 Sachem Street
Instructor
Office hours: Wednesday, 4–5pm in AKW 503
📖 Course Description
Cryptography provides strong security and privacy guarantees in well-defined mathematical models, but applying it to real-world systems is an art that must account for performance, cost, evolving adversarial threats, and user behavior. This course examines how cryptographic tools underpin digital infrastructure and protect users against powerful and evolving threats. Topics include TLS, anonymity systems such as Tor and DC nets, secure messaging, anonymous credentials, digital identity, and trusted execution environments.
Prerequisites
Grading
Coursework includes homework and written responses to reading assignments. Graduate students will present at the end of the semester.
- Undergraduate students: participation (20%), paper critiques (20%), problem sets and labs (60%)
- Graduate students: participation (20%), paper critiques (20%), problem sets and labs (40%), presentation (20%)
Homeworks
Use the LaTeX homework template for submissions.
Late days
- Each student gets one free late day.
- One late day equals a 24-hour extension.
- Each non-free late day incurs a 10% grade reduction.
- Dean’s extensions are honored; no other late days will be granted.
Lecture Schedule
Section I: Foundations
Section II: TLS
Attacks against TLS
Provenance of TLS sessions (zkTLS)
- Lab 2: Decrypting TLS traffic
- Written Assignment #3: Crypto and TLS
Section III: Messaging under Strong Adversaries
Censorship (guest lecture)
Student presentations: Loopix and Pudding
- Written Assignment #4: Anonymity
Section IV: Identity and Credentials
OPAQUE and federated authentication (SSO)
Anonymous credentials
March recess follows
Student presentations
- Written Assignment #5: Identity and Credentials
Section V: Securing Data in Use
SGX deep dive: remote attestation and sealing
Canceled due to NSF duties
TEEs and everything learned so far
Student presentations
Section VI: AI and Cryptography
What cryptography can and cannot do for AI
Lecture + one presentation