Quantum Key Distribution: Advantages, Challenges and Policy

The prospect of quantum computing threatens the security of modern encryption methods, putting our private communications at risk. With experts predicting the development of powerful quantum computers as early as the end of the decade, the urgency of transitioning to `quantum-safe’ communications is apparent. There are two classes of solutions available: post-quantum cryptography (PQC), which refers to communication algorithms designed to be safe against quantum computers, and quantum key distribution (QKD), a new technology with unique advantages and challenges. These solutions are not mutually exclusive, and this review argues that they are in fact complementary solutions to the threat of quantum computing. However, QKD has received criticism for being a less practical solution than PQC. This review makes the case for QKD and argues that it offers significant advantages which are not adequately recognised. I conclude that the development of QKD would benefit from increased government support and I provide policy recommendations for how to best support it.