"See the complete overview “Detailed overview of AQUAS Results” -
http://aquas-project.eu/documents/(s’ouvre dans une nouvelle fenêtre)The project AQUAS dealt with managing the interaction between safety, security and performance (SSP). This is a major problem for development and operation of embedded and future cyber-physical systems. Security features are necessary to ensure performance and safety in the face of attacks. However, conflicts may arise, e.g. when a security feature like encryption or authentication may slow down operation in ways that impair safety. Undetected conflicts are a special concern: they may require expensive redesign and/or product recalls, or cause mishaps (accidental or due to attacks), with harm to life and property, during operation of these products. Synergies are also possible between SSP, allowing savings, as when a precaution taken for safety also improves security. The automation also lowers certification costs for technology transfer.
So there is a need for Dependability Co-Engineering (DCE): managing SSP properties together at system level. This is difficult in current practice as SSP properties are covered by separate, specialised staff, methods and tools.Thus expected outputs from AQUAS are:
* a methodology supporting DCE for the entire PLC.
* application examples in five industrial use cases, supporting advances in current practices, methods and tools.
* analysis of the challenges for industry to adopt automated DCE and creating foundations.
* supporting evolution of relevant standards to account for the need for DCE.
For guidance in achieving these outputs we considered CE within a PLC phase, CE across all the PLC and finally how standards needed to evolve. Twelve objectives with metrics supported advancement.
To support uptake of DCE automation, major methodological advances were required. In AQUAS this is based on the concept of ""interaction points"" (IPs), points in the product lifecycle (PLC) when non-functional requirements of SSP are dealt with together, using suitable ""combined analysis"" (CA) methods, allowing identification of conflicts and synergies, and decisions to deal with them, supported by forecasts of their system-level SSP effects.
The AQUAS methodology seeks to both (1) improve system quality through holistic, system level SSP combined analyses and (2) do this cost-effectively by concentrating the CAs at the IPs alone, producing a low-overhead process for interaction between specialists and for crucial DCE-related decisions. This enables developers to:
- identify potential conflicts between SSP requirements of the system under development earlier in the lifecycle than would be otherwise possible;
- scope the space of trade-offs between SSP and seek acceptable compromises between the conflicting properties for the particular system;
- detect and exploit possible synergies between means for SSP;
- combine different CAs cost-effectively at each IP for better coverage of potential problems
- trace through the PLC the effects of decisions taken at each IP.
The work on methodology and uptake will lead to major societal enhancements: material living conditions, health, physical safety and for the environment."
