# Cyber Resilience Limitations in Space Systems Design Process: Insights from Space Designers
## 1 Introduction  
Contemporary modern society heavily depends on space infrastructure [1, 2]. The European Commission states the following: \"Space infrastructure is critical infrastructure on which services essential to the smooth running of our societies and economies and our citizens' security depend. It must be protected, and that protection is a major issue for the EU, which goes far beyond the individual interests of the satellite owners.\" [3]. The essential functions provided by space services are challenging to replace, highlighting their significance to society. Thus, the logical, physical, geographical, and cyber aspects of spaceinfrastructure form a complex system of systems, making it vulnerable to cascading and escalating failures that can greatly amplify the impact of any damage [2].  
Space infrastructure faces unique challenges due to its extreme size, power, and weight (SWaP) constraints. It must be cost-effective to launch, and once there, it is the ultimate unrecoverable remote system. Furthermore, in a cyberwar, space assets are susceptible to cyber-attacks like most predominantly digitised critical infrastructure [4]. According to _The Oxford Dictionary_, cyberwar is defined as _\"the use of computer technology to disrupt the activities of a state or organisation, especially the deliberate attacking of information systems for strategic or military purposes.\"_ and _\"cyberwar is asymmetric, which means it benefits lesser military powers as much as military goliaths\"_ [5]. The military use of space systems after the launch of Sputnik in 1957 [6] created new challenges and threats for space infrastructure due to its complex and unique multi-layer architecture and isolation [7]. The military potential of space systems was immediately recognised after the first satellite launch [6], turning space into a new potential war front. One contemporary example of such a potential threat is the launch of a Russian satellite that may serve as a weapon capable of inspecting and attacking other satellites in low Earth orbit [8].  
Therefore, the advances in new technologies and battlespaces have evolved from the old \"offensive-defensive\" paradigm [9]. As a result, cyberwar now takes place in a modern networked space with almost no rules of engagement, or at least not widely accepted, making it challenging to identify the enemy (threat actors) and often obscure motives [10; 11].  
This study examines the engineering challenges of integrating cyber resilience into space systems design. It focuses on the technical and organisational requirements necessary for creating a robust framework. The need for such a framework emerged directly from qualitative interviews with experts from the space domain, including engineers, cybersecurity specialists, project managers, and testers. These participants are also the stakeholders directly impacted by the findings, influencing their work in developing and securing space systems. Furthermore, the research identifies vital themes related to engineering practices, cybersecurity awareness, and the barriers to implementing cyber resilience in space projects. The insights gathered from these experts lay the foundation for developing a framework that addresses both technical and organisational demands, ensuring space systems remain resilient against cyber threats.