J. Warther
Green Hills Software, California, United States
Keywords: High Assurance Software, Real-Time, Cyber
As space becomes an increasingly contested and critical domain for national defense, the resilience and trustworthiness of onboard software and computing platforms are paramount. Real-time operating systems (RTOS), long relied upon in avionics for their determinism and reliability, are now central to military satellite operations, where mission assurance and cybersecurity must converge. This paper explores how high-assurance RTOS architectures—rooted in safety-critical aerospace standards—are being adapted to meet the rigorous demands of orbital warfare, satellite command and control, and autonomous payload management. Green Hills will discuss and provide lessons learned as to how application of proven avionics methodologies, such as DO-178C, AMC 20-193 can be implemented to the space domain, where real-time responsiveness must be matched by cyber resilience. The growing need for cryptographic isolation, secure boot chains, and fault-tolerant architectures in low-latency, bandwidth-constrained environments underscores the role of RTOS as a mission enabler. Green Hills expereince across GPS III, MGUE, and PNT as a enabler will be articulated. Finally, the paper considers policy and acquisition implications for developing space-grade cybersecurity capabilities that align with military readiness and survivability guidance or mandates