# Cyber Resilience Limitations in Space Systems Design Process: Insights from Space Designers
## 4 Results and Findings
### Challenges and Barriers  
We further explored the challenges and barriers faced in ensuring cyber resilience in space engineering while concentrating on \"Insider Threats and Cyber Resilience Gaps\" and \"Testing and Validation Challenges and Complexity Management Issues.\" These areas are critical for understanding the limitations and risks inherent in the current approaches to cyber resilience within the space sector. Insider threats represent a significant challenge to the cybersecurity and resilience of space systems [102]. Unlike external threats, insiders have legitimate access to the system and can exploit their knowledge and privileges to cause harm. Such threat is a concern in space systems, where the complexity and criticality of operations mean that any malicious action can have far-reaching consequences. Therefore,  
Figure 4: Inductive code frequency.  
the intricacies of space missions with high trust placed in personnel can create a unique environment where insider threats can be particularly devastating [103]. Addressing these threats requires a multi-faceted approach that includes robust access controls, continuous monitoring, and a culture of security awareness.  
The participants highlighted the lack of comprehensive insider threat management strategies, which were raised to further exacerbate the gaps in cyber resilience. Typically, organisations concentrate their efforts on perimeter defences, neglecting the need for internal surveillance and anomaly detection [104]. Effective insider threat management in space systems should incorporate advanced techniques such as behavioural analytics, which can identify unusual patterns of activity that may indicate malicious intent.  
The theme that caught our attention was the testing and validating of cyber resilience in space systems. Space systems have numerous interdependent components, each with its vulnerabilities [105]. Our analysis showed that experts raised concerns about the significance of thorough and continuous testing to ensure the systems can withstand cyber attacks.  
_\"The complexity of the end-to-end system, involving multiple parties, is a primary challenge to integrating cyber resilience. Additionally, change management and testing, with high rates of change, pose difficulties. The speed of detection and response to threats is critical, balancing response methods with vulnerabilities and understanding trade-offs, including the risk of over-protecting systems to the point of impeding legitimate access.\"--Lead Engineer, interview participant_  
Complexity management was noted as another crucial issue. The interconnected nature of space systems means that a vulnerability in one component can have cascading effects on the entire system [105]. Therefore, managing such complexity requires a holistic approach that considers the interactions between different components and the potential for emergent vulnerabilities. Techniques such as Model-Based Systems Engineering (MBSE) were indicated to be the preferred engineering approach, which can be instrumental in managing complexity by providing a comprehensive, model-driven framework for system design and analysis [63].  
The additional emergent theme was the need for stakeholders' understanding and alignment regarding the importance and prioritisation of cybersecurity measures in engineering projects. Our analysis showed that this difficulty requires effective communication and collaboration among stakeholders to foster a shared understanding of the critical role of cybersecurity and resilience in each project's success. The budget limitations to invest in the latest technologies and training were also raised as concerns.