Tag Archives: GSN

  • Getting ready for AI system certification

    Certification of AI systems is a complex process that includes both AI regulations and industry regulations. In particular, the AI Act Regulation (EU 2024/1689) defines the concept of high-risk systems for which additional requirements have been defined. For such a complex process, the use of assurance case gives the opportunity to effectively manage the development […]

  • Eight ways to ruin an assurance case

    An assurance case used in a systematic and professional manner can not only be useful for system certification, but also as a communication tool in the system assurance process helping in early detection of problems and decision-making. Its effectiveness stems from its focus on goals and building confidence. However, this can be lost if you […]

  • Assurance case automation in CI/CD pipelines

    The use of CI/CD tools (Continuous Integration and Continuous Delivery/Deployment) is increasingly common in the development of critical systems. The same CI/CD pipelines can also be used to automate the creation and maintenance of assurance cases including the argument structure and evidence, and also for the argument verification and status data updating. CI/CD process and […]

  • Eliminative Argumentation

    Eliminative argumentation is an alternative approach to building an assurance case. The argument is typically constructed positively and focuses on demonstrating why we believe the goal has been achieved. Eliminative argumentation relies on the constant questioning of “what if?”. The structure of the argument can be quite similar to that of a standard positive argument, […]

  • Managing system limitations in safety assurance cases (SOTIF)

    Safety cases are usually based on functional safety arguments to demonstrate that failures will not result in hazardous situations. But accidents may have causes related to the system behaviour different than failures. This is where SOTIF comes in. This stands for Safety of the Intended Functionality. What does it mean? It covers mitigation of hazard […]

  • LTAC – Simple text assurance case format

    When working with assurance case arguments, a simple text argument format can be useful. This should be understandable to humans and usable with AI tools, while also being formally defined so this can be imported into assurance case editors. For this purpose, we are introducing LTAC –  Lightweight Text Assurance Case. It’s a simplified text […]

  • Using confidence arguments in assurance cases

    Confidence arguments help to justify that main arguments in assurance cases are sound and trustworthy. While the main argument directly addresses system safety or security, the purpose of the confidence argument is to answer the question why we should trust that the main argument is right. Some standards and guidelines, and also some certifiers require […]

  • Building strong assurance cases

    Strong assurance cases are achieved by building confidence in the validity of reasoning steps and demonstrating how defeaters are handled. These two approaches present two different directions of argumentation. The first one focuses on providing sound basis for the argument while the second aims at defending it against known defeaters. Which approach is more effective […]

  • Static and dynamic evidence in PREMIS

    An assurance case is a structured argument supported by evidence. It can a static safety case referring to static evidence and frozen in a Safety Case Report. And it can a dynamic object referring to dynamic evidence that can evolve. For example the evidence may include Safety Performance Indicators based on measurements during system operation. […]

  • Easier GSN argument development

    Editing GSN arguments in PREMIS is now easier, you can drag elements from the tray directly to the diagram. At the same time, the performance of GSN diagrams in the new version of PREMIS has been improved. Especially generating diagrams is now very fast. The new version also includes improvements in the management of assessments, […]

  • GSN and SACM modular assurance cases

      Both the GSN Community Standard and OMG SACM specify modular assurance cases, though from different perspectives. The GSN Standard focuses on the logical dependencies between elements in different argument modules. SACM, on the other hand, introduces the concepts of interfaces and bindings in its metamodel. In practice there are no conflicts between the two […]

  • Safety and security co-assurance

    Both system safety and security are critical goals, but they are not always compatible. You have to consider safety – security relations when developing a system assurance case. A solution to this problem, a Safety-Security Assurance Framework (SSAF), has been proposed by the latest publication of the SCSC Security Informed Safety Working Group. The main […]