Analysing Fault-Tolerant System using KAOS/FAUST

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Analysing Fault-Tolerant System using KAOS/FAUST

• C. Ponsard, P. Massonet, J.F. Molderez (CETIC)
• A. van Lamsweerde (UCL/INGI)

Short presentation Demo REFT05, Newcastle (UK)
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Key Idea

• B Method
• from specification to code
• correct by construction approach
• moving towards requirementsSystem B models of
  both SW/HW/environment
• KAOS
• similar approach at requirements level
• also refinement approach (property based)
• reason the design of the composite system
• explore alternative designs, reason about agent
  responsibilities
• assess/improve the robustness of the system
• tool support FAUST
• based on Objectiver semi-formal RE platform
  (providing conceptual repository, graph edit,
  doc. generation,)
• Seamless integration for optimal communication
• looks complementary and worth investigating
• current status of on-going work

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Structuring Properties using a Goal Model (with
KAOS)
HOW?
WHY?
On (tr, b) ? ? On (tr, next(b))
On(tr,b) ? Gonext(b) ? ? On(tr,next(b))
On(tr,b) ? ? Gonext(b)
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Being Pessimistic
...
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Driving the elaboration process
NoTrainCollision
Goal Model
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Some Derived Artefacts
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Connection with B/Rodin

• B moving towards requirements
• System B models of both SW/HW/environment
• Requirements gap is a well known problem Abrial
• Refinement approach
• Property refinements in KAOS
• Operational refinements in B
• Benefits for direct engineering
• Identifying key properties
• Building models easier to prove
• Benefits for reverse engineering
• Structuring key properties
• Explaining model to stakeholders for
  validation/acceptance
• semi-formal notations, animation, document
  generation,
• Better documentation less flat document, richer
  traceability, checks

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Agenda for K2B

• Practical Scope
• Composys style (Clearsy use of System-B)
• industrial cases (automotive/railway)
• From KAOS models to B models
• Automated generation of initial B specification
• From set of operation assigned to agent
• Attach requirements/ higher level goals
• Animation tool ?
• From B models to KAOS models
• Guidelines for building goal/object/agent models
• B aware document generation template
• Means
• Applied research at CETIC
• Collaboration with ClearSy
• Student task force from UCL (Belgium)

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Demo

• during coffee break

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FAUST Architecture
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Interface du vérificateur de raffinements
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Interface de lanimateur