Recent Progress in Quantum Key Distribution Network Deployments and Standards

Quantum key distribution (QKD) provides in principle unconditional security of key sharing based on the laws of physics only. In the last decade, several experimental and commercial QKD networks have been built and operated worldwide. Demonstrational applications of QKD in financial institutions, government networks, and critical infrastructures such as the power grid have been initially explored. However, large-scale deployment and full-scale commercialization of QKD networks still faces some technological and standardisation challenges. In this paper, recent developments and in-field deployments of QKD networks are reviewed and advancements in QKD standardisation are also discussed.