Foundations of Cryptography

CS60088, Spring 2026, LTP: 3-1-0


Class Timings MON: 15:00--16:55; TUE: 14:00--15:55
Venue CSE 120
Instructors Monosij Maitra and Somindu Chaya Ramanna
Teaching assistants Soumojit Chatterjee

Prerequisites

We assume basic familiarity with probability theory, algebraic structures (groups, rings, fields), linear algebra and algorithms. Some exposure to computational complexity is useful as well. These topics will not be covered in the course. No prior exposure to cryptography is necessary.

Syllabus (Tentative)

References

Evaluation (tentative)

The evaluation for this course will be based on the mid-sem, end-sem examinations and a term paper. Details are below.
30%: End-sem examination
30%: Mid-sem examination
40%: Term Paper + Presentation, Tutorials

Tests/Exams

[Questions will be uploaded here.]

Lectures

Week Date Topics Covered
1 5 January Introduction
6 January Perfect secrecy: definition, equivalent definitions, one-time pads; Limitations of perfect secrecy
2 12 January Shannon's theorem; Computational secrecy -- motivation, formalising security under different threat models; Reductionist arguments and hardness assumptions,
13 January Pseudorandomness; Pseudorandom generators (PRGs); Using PRGs to construct secure encryption
Tutorial 1 - Perfect Secrecy
3 19 January Variable-length and multiple encryptions, Security against Chosen Plaintext Attacks
Pseudorandom functions
20 January IND-CPA-secure encryption from PRFs
Modes of Operation
4 26 January No Class - Institute Holiday (Republic Day)
27 January Tutorial 2 - Computational secrecy: IND-EAV security, PRGs, IND-CPA security, PRFs
5 2 February
3 February
6 9 February
10 February
7 16 February
17 February
18 - 26 February Mid-Semester Examination
8 2 March
3 March
9 9 March
10 March
10 16 March
17 March
11 23 March
24 March
12 30 March
31 March No Class - Institute Holiday (Mahavir Jayanti)
13 6 April
7 April
14 13 April
14 April
15 20 April
21 April No Class
20 - 30 April End Semester Examination

Useful Links/Resources