CS 255 Course Overview

(Winter 2001)



This course is an introduction to the basic theory and practice of cryptographic techniques used in computer security. We will cover topics such as encryption (secret-key and public-key), digital signatures, secure authentication, electronic commerce (anonymous cash, micropayments), key management, cryptographic hashing, Internet voting systems, and a bit of zero-knowledge protocols.


The course requires a basic understanding of probability theory. Some knowledge of modular arithmetic will be helpful but not required. The course is intended for advanced undergraduates and graduate students.

Textbook Information

We will be using two books:

  • Cryptography Theory and Practice by D. Stinson.
  • Cryptography and Network Security, Second edition, by William Stallings.
  • Optional: Applied cryptography by B. Schneier.
  • Optional: Handbook of Applied Cryptography by A. Menezes, P. Van Oorscho, S. Vanstone.  Free!

and research papers handed out in class.


  • There will be four sections given by the TA's during the quarter.
  • Sections will be held at Gates B01 from 4:15 - 5:30 (live on channel E3) on the following dates:
    • January 25th, 
    • February 8th,
    • February 22nd, (5:45pm-7:00pm, Gates B03)
    • March 8th.
  • Attendance at the sections is optional.  

Homework Assignments

  • There will be three written homework assignments and two programming project.
  • You may collaborate when solving the written assignments, however when writing up the solutions you must do so on your own. 
  • Both programming projects can be done in pairs.
  • You must hand in all three homework assignments and the two programming projects.
  • Some of the assignments will contain extra credit questions. You must solve extra credit questions on your own.
  • Homework assignments will be graded on a scale of 0 to 10.
  • Assignments should be handed in on the due date.


There will be a final exam. No midterm exam.


Final placement in the class will be determined by the following formula:

0.4 H + 0.3 P + 0.3 F

  • H is your average score on the three written homework assignments.
  • P is your average grade on the two programming projects.
  • F is your final exam score.

Last update: January 09, 2001 by Dan Boneh