Information Assurance

Educational Series on Hash Functions

Educational Series on Hash Functions

This video-course is intended to give an overview of the nature of hash functions, their cryptographic and security properties, and time-stamping as a practical usage for hash functions.

The first part of the video lecture series below gives an overview of what hash functions are. In the second part, we take a look at the cryptographic security requirements for hash functions. The third part of the series deals with the matter of security properties of hash functions.

In the fourth part, we explore hash functions which are provably secure but inefficient and hash functions which can be used practically. The fifth part in the series shows a practical application of hash functions on the example of time-stamping.

In the sixth and seventh part of the lectures, we look at security requirements for hash functions used in time-stamping and ways of proving how specific hash functions meet requirements for hash functions.

Ahto Buldas and Margus Niitsoo

Lecturer Ahto Buldas is a professor at Tallinn University of Technology and University of Tartu, specializing in complexity theory, combinatorics, cryptography, and data security. He has worked extensively with hash functions and their usage in time-stamping and together with Margus Niitsoo in 2010 showed how global scale time-stamping can be used with 256-bit hash functions.

Hash Functions Lecture 1

Short Identifiers for
Large Files

Hash Functions Lecture 2

Cryptographic Security Requirements for Hash Functions

Hash Functions Lecture 3

Relations Between the Security Properties of Hash Functions

Hash Functions Lecture 4

Provably Secure vs Practical Hash Functions

Hash Functions Lecture 5

Time-stamping as an Application for Hash Functions

Hash Functions Lecture 6

Security Requirements for Hash Functions Used in Time-Stamping

Hash Functions Lecture 7

Security Proofs for Time-Stamping