Over the last four decades, Modern Cryptography has developed into a field with solid mathematical foundations. In addition to developing the idea of "provable security," investigations into the fundamental nature of secrecy and security threw open a range of new possibilities that go well beyond encryption. This course will introduce you to some of these tools, as well as basic concepts needed to formally define and prove their security.

__Course contents.__
The topics we will try to cover (as time permits) include

- Secure Multi-Party Computation,
- Private Information Retrieval, Symmetric Searchable Encryption, Oblivious RAM,
- Functional Encryption, (Fully) Homomorphic Encryption, Obfuscation,
- Leakage-Resilience, and
- specialized applications
like
*Secure Voting*and*Digital Cash*.

The course project will give you a chance to read up on topics not covered in the lectures and/or implement an advanced cryptographic tool.

__Graded Work.__ The graded work involves two exams or quizzes (60%), a
few homework assignments (20%) and a team project (20%). The projects will be
evaluated based on a presentation and either a report or a demo (depending on
the nature of the project), and meeting(s) with the instructor prior to that.
Some sample topics for the project will be provided later on. The quiz
schedule will be announced later.

The students are expected to regularly attend all the lectures. Since the lectures include a lot of material that will not be covered by assignments or quizzes, one grade point is reserved for registering 80% attendance.

__Background.__ This course will have a theoretical flavour: you will
need to be comfortable with mathematical definitions and proofs ("mathematical
maturity"). Specific mathematical topics that will be encountered are
elementary probability, linear algebra and discrete mathematics.

__Teaching Assistant:__
Rajeevalochana M. R.

- Previous edition
- Crypto Courses Elsewhere:

- Reference Books:
- MPC and Secret-Sharing
- Goldreich (foundations) (Also freely downloadable A Primer)

- Background material:
- Basic probabililty: Chapters 14-18 of Mathematics for Computer Science from MIT OpenCourseWare.
- Basic Linear Algebra

- Lecture 00: (Jan 7): Introduction [html|pdf|print]
- Lecture 01: (Jan 10): Indistinguishability [html|pdf|print]
- Lecture 02: (Jan 17): Secret-Sharing [html|pdf|print]
- Lecture 03: (Jan 21): Secret-Sharing (ctd.) [html|pdf|print]
- Lecture 04: (Jan 24): MPC from Secret-Sharing: Passive, Linear Functions [html|pdf|print]
- Assignment 1 (Due Feb 7)
- Lecture 05: (Jan 28): MPC from Secret-Sharing: Passive, Honest-Majority, All Functions [html|pdf|print]
- Lecture 06: (Jan 31): MPC: Passive GMW [html|pdf|print]
- Lecture 07: (Feb 4): MPC: Yao's Garbled Circuit [html|pdf|print]
- Lecture 08: (Feb 7): Simulation-Based Security [html|pdf|print]
- Lecture 09: (Feb 11): MPC: Security against Active Corruption [html|pdf|print]
- Lecture 10: (Feb 14): MPC: GMW Paradigm. Composition. [html|pdf|print]
- Lecture 11: (Feb 18): MPC: UC Theorem. (Im)possibility of UC security. [html|pdf|print]
- Lecture 12: (Feb 21): MPC: UC-Secure OT [html|pdf|print]
- Lecture 13: (Mar 4): MPC: BGW Protocol (Active, Honest-Majority) [html|pdf|print]
- Assignment 2 (Due Mar 17)
- Lecture 14: (Mar 7): MPC: More Dimensions [html|pdf|print]
- Lecture 15: (Mar 11): MPC: Beyond General MPC [html|pdf|print]
- Quiz 1 on MPC (Mar 13)
- Lecture 16: (Mar 14): Homomorphic Encryption [html|pdf|print]
- Lecture 17: (Mar 18): Homomorphic Encryption. Application to PIR. [html|pdf|print]
- Lecture 18: (Mar 25): Encryption Beyond Group Homomorphism: Bilinear Groups [html|pdf|print]
- Lecture 19: (Mar 28): Lattice Cryptography [html|pdf|print]
- Lecture 20: (Apr 1): Fully Homomorphic Encryption - I [html|pdf|print]
- Lecture 21: (Apr 4): Fully Homomorphic Encryption - II [html|pdf|print]
- Lecture 22: (Apr 8): Functional Encryption - I [html|pdf|print]
- Lecture 23: (Apr 11): Functional Encryption - II [html|pdf|print]
- Lecture 24: (Apr 15): Obfuscation [html|pdf|print]
- Assignment 3 (Due Apr 29)
- Lecture 25: (Nov 9): Miscellany - iO, Shallow Circuits [html|pdf|print]
- Quiz 2 (April 30)
- Project Presentations (May 5)