This course is part of the Mastermath program.

**Prerequisites:**Basic knowledge of algebra (including knowledge of groups, rings, fields) and discrete probability theory.**Aim of the course:**This Master’s level course provides an introduction to modern cryptography, the science of securing communication and computation against different forms of adversarial behaviors. A preliminary outline of the course is as follows. We will start with basic concepts of cryptographic theory such as one-way functions. We will see how to leverage one-wayness to generate pseudorandomness and discuss implications to complexity theory. Subsequently, we will look at different notions of symmetric-key primitives including symmetric-key encryption, message authentication codes and collision-resistant hash functions. To construct public-key encryption schemes we will build on number-theoretic and algebraic hardness assumptions. We will then move on to authentication (and beyond) and discuss digital signature schemes, sigma protocols and zero-knowledge proofs. The final block of the course will be dedicated to the basics of secure multi-party computation.**Rules about Homework/Exam:**To be announced.**Lecture notes/Literature:**To be posted.**Lecturers:**Lisa Kohl (Cryptology Group, CWI Amsterdam), E-mail: Lisa.Kohl(at)cwi.nl