CS255: Introduction to Cryptography

Introduction to Cryptography

Winter 2023

Cryptography is an indispensable tool for protecting information in computer systems. This course explains the inner workings of cryptographic primitives and how to use them correctly.


Course syllabus (and readings)
Course overview (grading, textbooks, coursework, exams)
Lectures: Monday, Wednesday, 1:30-2:50pm, Gates B01
Sections: Friday, 4:30-5:20pm, room 160-B40.
Questions for CAs: cs255ta@cs.stanford.edu or use Ed Discussion
Videos: cs255 online   (for video lectures and slides covering the material in class)

Final Exam

The final exam will be a take home exam. You will have three hours in a 24 hour window to complete the exam. Please use gradescope to submit your answers.

The exam will take place on Wed, March 22, 2023, beginning at 9am PT.

Previous final exams:

2023.pdf ,   2022.pdf ,   2019.pdf ,   2018.pdf ,   2017.pdf ,   2016.pdf ,   2015.pdf ,   2014.pdf ,   2013.pdf ,   2012.pdf.

Practice work sheet


All homework submission is to be done via Gradescope. Please use course code PX6887 to sign up. Note that Gradescope requires that the solution to every problem start on a new page.

Homework #1:   [html]
Due: Jan. 17
Homework #2:   [pdf]
Due: Feb. 7
Homework #3:   [pdf]
Due: Feb. 21
Homework #4:   [pdf]
Due: Mar. 15


Project #1 (password manager):   pdf   starter code
Due: Tue., Feb. 14, 11:59pm
Project #2 (chat client):   pdf   starter code
Due: Tue., March 7, 11:59pm