EphemeriShield - Defence Against Cyber-Antisatellite Weapons

Mitigating the risks associated with space system operations, especially in Low Earth Orbit, requires a holistic approach, which addresses, in particular, cybersecurity challenges, in addition to meeting the data acquisition requirements the mission needs. Space traffic management systems form no exception to this rule, but are further constrained by backward compatibility requirements that sometimes are based on decades old foundations. As a result, some space situational awareness systems continue to operate with object catalogues and data dissemination architectures that are prone to failures, not to mention adversarial actions. Proof-of-Concept papers, demonstrating this vulnerability in example attacks on space object ephemerides distribution channels have already been published and show the urgency in rethinking the way we build such high-critical infrastructure. Leveraging recent developments of distributed systems theory and concepts from multi-party consensus in limited-trust environments and in the presence of malicious actors, we designed a more secure system for orbital object ephemerides distribution, ultimately targeting at increasing the safety of satellite operations. This paper presents EphemeriShield, a distributed ephemerides storage and distribution system, aiming at maintaining safety and security guarantees in presence of active attacker or unfortunate fault. Using our EphemeriShield prototype setup, we were able to prove its ability to mask attacks and local faults that otherwise would lead to unnecessary maneuvers. Wide adoption of EphemeriShield may help satellite system operations to become safer and less vulnerable to intentionally adversarial activities, which improves the overall sustainability of space.