This first blog post in our series about differential cryptography describes the design of symmetric block ciphers. These are encryption algorithms, where the same secret key is used for encryption and decryption.
In software dealing with security, randomness is often necessary to generate keys or tokens for resetting passwords or identifying sessions. There, randomness is required to be unpredictable for an attacker. However, sometimes developers do not use cryptographically secure pseudo random number generators (CSPRNG) in this scenario. Instead they utilize faster pseudorandom number generators (PRNG). Consequently, the question arises how hard it is to attack a common (not cryptographically secure) random number generator.
In this article I am going to highlight some of the issues concerning the current state of post quantum cryptography. This article is written for readers who want a high level overview and are not much concerned with technical details.
The first part explains how security of cryptographic algorithms is determined in theory. Next, the notion of post quantum cryptography is introduced. Eventually, selected aspects if one decides to use post quantum cryptography are highlighted.