Security in Embedded Avionic Systems using the Concept of Multiple Independent Levels of Security

This thesis adapts the system design concept of Multiple Independent Levels of Security (MILS) as software architecture for a high-assurance use case - an avionic gateway to control data flows. Additionally, the thesis analyzes solutions to perform I/O operations securely. For this, hardware requirements are formulated and applied in a hardware audit on a special I/O accelerator. Last, this thesis focuses on methods to gain assurances for correct implementation. First, the Decentralized Label Model is applied to the C language and connected to MILS properties. Second, this thesis discusses compositional certifications in the Common Criteria and proposes a new certification strategy that matches with MILS.