The Foundations of Concrete Security

Symmetric cryptography considers the setting where communicating parties share a secret, unknown to the adversary, such as a key or a password. This is the type of cryptography that ends up being used the most, yet actually proving the security of symmetric algorithms is often very challenging. This is in particular due to the expectation that theorems should give precise quantitative lower bounds on the effort needed to compromise a scheme, and this often requires a deep understanding of complex probabilistic processes.

This series of lectures will cover recent advances in the analysis of symmetric cryptography, with a focus on generic techniques. Topics will include:

1. tools for information-theoretic indistinguishability proofs;
2. measuring and proving multi-user security;
3. the analysis of password-hashing methods, including memory-hard functions.

No prior expertise in the area will be assumed - only an understanding of basic probability theory and cryptographic security definitions will be needed.