Cryptography, 4003-482-01/4005-705-01, Winter 2010/11

Course Description

This course provides an introduction to cryptography and its relation to security. It covers classical cryptosystems, private-key cryptosystems (including DES and AES), and public-key cryptosystems (including RSA). The course also provides an introduction to integrity and authentication.

Course Outcomes

  1. Students will be able to implement and cryptanalyze classical ciphers.
  2. Students should demonstrate a basic understanding of modern private-key cryptosystems and ways to cryptanalyze them.
  3. Students should demonstrate a basic understanding of modern public-key cryptosystems and ways to cryptanalyze them.
  4. Students should demonstrate a basic understanding of the mathematical concepts underlying modern cryptography.
  5. Students should demonstrate a broad understanding of the field of cryptography and its relation to security.

Course Web Page


Ivona Bezakova
bldg. GOL(70), room 3645
Email: my_initials at (please replace my_initials by ib)

Office hours

(New, as of January 10):   Mo   2-3pm and 8-8:30pm,   We   8-8:30pm,   Th   11am-12pm and 1-2pm,   office 70-3645
(For the evening office hours, please come at 8pm - I may leave with the last person.)

Asking questions via email seems to work well for many people.


Monday/Wednesday, 12:00-1:50pm, 70-3435.

Required Book

Trappe and Washington, Introduction to Cryptography with Coding Theory, second edition, Prentice-Hall, 2006.

Other Materials

Slides from class and other related materials will be posted at the reading and homework assignments webpage.


CS4 (4003-334) and Discrete Math (1016-265).

The Work

Homework Assignments

There are eight homework assignments, one per week except for the first week and the weeks of the midterm. Each homework assignment will be collected and graded. Homework assignments are due on Friday at 4pm, and are usually posted at least six days before they are due. The actual assignments will be available on the reading and homework assignments page.

Unless it is specifically stated otherwise, you may work on and submit your homework alone or as a pair. If you choose to work as a pair, both of you should contribute significantly to every part of the homework. You should submit only one copy of the homework with both your names on it.

Whether you submit on your own or with a partner, discussing the homework assignments and solution strategies with your classmates (including those in section 2) is encouraged. However, the actual solutions should be completely your own. You are not allowed to discuss the homework with people other than your classmates, the theory tutors, and the instructor. You are also not allowed to look up the answers to your homework and you should be able to explain all of your homework to the instructor.

Your homework submissions must be submitted by Friday, 4pm sharp. You have the following submission options:

No late assignments will be accepted. The lowest homework grade will be dropped for 4005-705. The lowest two homework assignments will be dropped for 4003-482. However, a zero for cheating will not be dropped.

The instructor will answer homework questions that arrive before 2:30pm on Thursday. The instructor will try to reply to your questions within 24 hours.

Midterm Exam

The midterm exam is scheduled for Wednesday, January 19, 12:00-1:50pm, location 70-3435.

Final Exam

The final exam is tentatively scheduled for Friday, February 25, 10:15am-12:15pm, location 70-3435. You may also opt to take the final exam with section 02 on Monday, February 21, 12:30-2:30pm, location 70-3435.

Exams can not be made up except for real emergencies in which case proper documentation (like a doctor's note) will be required or if you can not take an exam because of religious reasons. If at all possible, you should contact me prior to the exam. Oversleeping, cars that don't start etc. do not constitute a valid excuse.


Numerical grades will be converted to letter grades according to the following scale:
&ge 88%: A; 77%-88%: B; 66%-77%: C; 55%-66%: D; < 55%: F. However, your final grade will never be more than one letter grade higher than your (weighted) average exam grade. In addition, if your (weighted) average exam grade is below 55%, you fail the course.


In addition to all of the usual support services RIT and the CS department offer, the CS theory faculty are offering their own tutoring service, featuring very qualified CS students. The tutoring takes place in the CS tutoring center (70-3660). The tutors will help with theory (380/700), algorithms (515/800), and basic questions about cryptography (482/705). For hours, see the theory tutoring page.

One rule about tutors: They will not do your homework for you.

Disputing Your Grade

If you feel that an error was made in grading your homework or exam, you have one week from the moment the graded work was handed back to dispute your grade. All grading issues should be taken up with the instructor; do not discuss grading issues with graders and tutors! All grades will be posted on myCourses.

Students with Disabilities

RIT is committed to providing reasonable accommodations to students with disabilities. If you would like to request accommodations such as special seating or testing modifications due to a disability, please contact the Disability Services Office. It is located in the Student Alumni Union, Room 1150; the Web site is After you receive accommodation approval, it is imperative that you see me during office hours so that we can work out whatever arrangement is necessary.

Academic Honesty

The DCS Policy on Academic Honesty will be enforced.

You should only submit work that is completely your own. Failure to do so counts as academic dishonesty and so does being the source of such work. Submitting work that is in large part not completely your own work is a flagrant violation of basic ethical behavior and will minimally be punished with failing the course.