CITADEL is based on MILS, an approach featuring modular construction and compositional assurance, reducing the time and cost for development, certification, and maintenance of dependable systems. The MILS platform, based on a separation kernel, manages physical resources while establishing and enforcing a verified application architecture.

Two previous research and development projects partly funded under the European Union  Framework Programme 7 provide the basis for the technology innovations that will be developed in the CITADEL project:

• D-MILS: The mission of the D-MILS project was to MILS to support distributed systems environments and to provide new tools for the design, analysis, verification, compositional implementation and certification of scalable and affordable trustworthy architectures.


• EURO-MILS: The mission of the EURO-MILS project was to develop a solution for virtualisation of heterogeneous resources and provide strong guarantees for isolation of resources by means of Common Criteria certification with usage of formal methods.

CITADEL will further extend the MILS approach by adding dynamic reconfiguration to the MILS platform, and Monitoring and Adaptation Systems enabling resilience to adversity while preserving vital system properties.