Method of management of remote operations

Abstract

A method of scheduling encryption key delivery communication sessions in a satellite quantum key distribution system comprising a constellation of one or more satellites and a plurality of user ground stations comprises producing a list of user ground stations requiring encryption keys. For each satellite of the constellation of satellites, determining a region of the earths surface within which the satellite can carry out encryption key delivery communication sessions to user ground stations using a quantum optical communications link during a scheduling period. Obtaining a cloud cover map. Comparing the locations of the listed user ground stations, the determined regions of the earths surface for the constellation of satellites, and the cloud cover map, to identify listed user ground stations to which encryption key delivery can be carried out by the constellation of satellites during the scheduling period. Determining which of the identified user ground stations each satellite of the constellation of satellites will carry out encryption key delivery communication sessions with at different times in the scheduling period based upon one or more of: an amount of unused encryption keys at each identified user ground station; and an expected time duration before each identified user ground station runs out of encryption keys.