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Revisiting the determination of cryptoperiods for authentication primitives in telecommand, telemetry, and payload links

The transition of space missions concepts from an all-in-the-clear communications to approaches including security mechanisms demands a sound cryptographic key infrastructure to be in place to properly support secure operations. One of the factors in that key management is the definition of cryptoperiods that are tailored to the space context. Approaches used on the ground very often cannot be directly applied to the space segment. Some previous works investigate some aspects of key management. This work addresses the problem of defining cryptoperiods for authentication mechanisms by revisiting and refining some previous approaches. A detailed methodology is devised for a broad range of space mission's concepts and attack scenarios, which allows for the definition of cryptoperiods for TC and TM, for both LEO and GEO missions. The results reported in this paper are crucial to precisely define authentication cryptoperiods for the space segment and consequently properly support security mechanisms employed in space operations.