A system and method for satellite quantum key distribution

摘要

A method of scheduling and managing key data in a satellite quantum key distribution system 100 comprising a constellation of one or more satellites 1 and a plurality of user ground stations 2. The method comprises using a satellite of the constellation of satellites to deliver key data to a user ground station using a quantum communication link; at the user ground station, storing the delivered key data and reporting the amount of delivered key data; using the satellite to deliver key data to at least one other user ground station requiring common encryption keys with the user ground station using a respective quantum communication link; at each other user ground station, storing the delivered key data and reporting the amount of delivered key data, based upon the reports, determining an amount of the delivered key data which is commonly stored at all of the user ground station and the at least one other user ground station and instructing the user ground station and the at least one other user ground station to release the commonly stored delivered key data