# ITC8240 Cryptography (2020)

## Course information

Code: ITC8240 Cryptography

ECTS: 6

Assessment: examination

Instructors:

- Ahto Buldas ahto dot buldas at taltech dot ee
- Aleksandr Lenin aleksandr dot lenin at taltech dot ee

## E-learning process and amended grading criteria

**Lecture slides** are uploaded regularly to the course webpage. Students study them individually.

**Practice** problem sets are uploaded regularly to the course webpage for individual practice.

**Homeworks** will be given out to students on a weekly basis. A homework will contain 2-3 exercises from practice problem set in the course webpage.

- Everyone is encouraged to practice and solve all of the problems allocated for practice.
- The 2-3 designated tasks selected from the entire set, will be compulsory for everyone and constitute a homework.
- Homeworks will be given out normally on Fridays, and a regular due time to upload submissions is Wednesday next week. In exceptional cases, the deadline may be extended to the next Friday.
- Homework solutions will be uploaded and made available for public access during the weekend following the extended deadline on the second Friday.
- No submissions are accepted once the solution is published.
- Submissions must be uploaded to the Moodle environment.

**Grading**: The uploaded solutions will be graded, and the course grade will be a (non-weighted) arithmetic mean of all the homework grades.

**Communication** will be organized using a Moodle forum where the students can ask questions and receive answers. The primary objective of the forum is to facilitate bidirectional communication. All the students can see all the questions and all the answers. Forum shall remain the primary means of communication, reserving email correspondence to private questions and requests.

## Announcements

- 3/21/2020 Homeworks are up, the first one is available for public access.
- 3/29/2020 Due date of Homework 1 has been extended to April 3.
- 3/29/2020 Homeworks 2 and 3 are up.
- 4/3/2020 Due dates of homeworks 1 and 2 have been extended to April 8.
- 4/172020 Homework 4 is up.
- 5/8/2020 Homework 5 is up.

## Lectures

- Simple Cryptosystems and Attacks
- Theory Of Unbreakable Ciphers
- Attacks Against Classical Ciphers
- Key Establishment
- Limited Adversaries
- RSA Cryptosystem
- RSA Failures
- Signatures and hash functions

## Exercises

- Information Theoretic Security
- Elementary Cryptanalysis
- Index Of Coincidence
- Bachmann-Landau Asymptotic Notation
- Complexity
- RSA Cryptosystem
- Attacks on RSA
- RSA (in)security proofs
- Signatures and Hash Functions

## Assignments

- Assignment 1. Due date: March 2nd.
- March 20 Homework: solve tasks 13, 18, 19 from Complexity problem set. Due date: April 8.
- March 29 Homework: solve tasks 3,4,5 from RSA Cryptosystem problem set. Due date: April 8.
- April 3 Homework: solve tasks 1,2,3 from Attacks on RSA problem set. Due date: April 8.
- April 17 Homework: solve both tasks from RSA (in)security proofs. Due date: May 1.
- May 8 Homework: solve all the tasks from Signatures and Hash Functions. Due date: May 22.