About this course: Welcome to Cryptographic Hash and Integrity Protection! This course reviews cryptographic hash functions in general and their use in the forms of hash chain and hash tree (Merkle tree). Building on hash functions, the course describes message authentication focusing on message authentication code (MAC) based on symmetric keys. We then discuss digital signatures based on asymmetric cryptography, providing security properties such as non-repudiation which were unavailable in symmetric-cryptography-based message authentication. This course is a part of the Applied Cryptography specialization.