Symmetric-key cryptanalysis by quantum computers

Abstract

Cryptography is widely used and implemented, particularly in a modern-day setting. Of note to the field of cryptography is the advent of quantum computing in speeding up computations. Particularly, existing asymmetric-key cryptographic schemes have already been found to be broken in a post-quantum setting, through the ability of quantum algorithms in solving difficult mathematical problems such as integer factorisation and discrete logarithms. In contrast, current symmetric-key cryptographic schemes are touted as quantum resistant, and it is often assumed that merely an increase of key length is needed to update current schemes in a post-quantum setting. Hence this project analyses the security of symmetric-key cryptography schemes against quantum computers, particularly compared against recent developments in classical cryptanalysis.