An updated analysis of satellite quantum-key distribution missions

Understand

Quantum key distribution (QKD) is a cryptographic method enabling two parties to establish a private encryption key.

• The range of communication of ground-based QKD is limited to an order of 100km, due to in-fibre attenuations and atmospheric losses, and the development of quantum repeaters remains technologically challenging.
• While trusted-node links make communication over large distances possible, satellite-QKD is required for communication over global distances.
• By using satellites equipped with high-quality optical links, satellite-QKD can achieve ultra-long-distance quantum communication in the 1000-km range.