Post-Quantum Cryptography: Current state and quantum mitigation
Ward Beullens, Jan-Pieter D’Anvers, Andreas Hülsing, Tanja Lange, Lorenz Panny, Cyprien Delpech de Saint Guilhem, Nigel P. Smart
Abstract
This study provides an overview of the current state of affairs on the standardization process of Post-Quantum Cryptography (PQC). It presents the 5 main families of PQ algorithms; viz. code-based, isogeny-based, hash-based, lattice-based and multivariate-based. It also describes the NIST Round 3 finalists for encryption and signature schemes, as well as the alternative candidate schemes. Given that the NIST process will still run for a few years, the last chapter offers 2 proposals that system owners can implement now in order to protect the confidentiality of their data against a quantum capable attacker; namely hybrid implementations that use a combination of pre-quantum and post-quantum schemes, and the mixing of pre-shared keys into all keys established via public-key cryptography.