Paper 2019/1374

A Survey of Digital Signing in the Post Quantum Era

Teik Guan Tan and Jianying Zhou

Abstract

Public key cryptography is threatened by the advent of quantum computers. Using Shor’s algorithm on a large-enough quantum computer, an attacker could cryptanalyze any RSA/ECDSA public key, and generate fake digital signatures in seconds. In this paper, we profile all 9 digital signature candidate algorithms within NIST’s post-quantum cryptography contest round 2, plus stateful hash-based signatures, and evaluate their suitability against 11 different industry applications. We have found that Falcon, a lattice-based digital signing algorithm, when supplemented with XMSS/LMS hash-based signatures, can best meet all of the application requirements if improvements in key generation and key sizes are achieved.