TRAK Architecture Framework MetamodelClaim, Argument and Evidence (CAE) Tuples
Part of the TRAK Metamodel provides a way to describe Claims, Arguments and Evidence. This is typically used in assurance, for example, to describe how and why a requirement is met and how the design supports this. The application areas are therefore:-
- design verification or assurance
- safety assurance cases
- security assurance - to describe how the proposed design addresses threats (hazards) and mitigates the risks
TRAK Metamodel Tuples Involving Claim, Argument and Evidence
Establishing the Claim
The tuples that the TRAK metamodel provides to describe the Claim are:-
- the source of the Claim:
- Organisation makes Claim
- Role makes Claim
- the subject of the Claim:
- Claim about Architecture Description Element (where Architecture Description Element = any element allowed in a TRAK view)
- Claim about Contract, Requirement, Standard
- Claim about System
- Claim about Organisation
- ...
- Claim about Architecture Description Element (where Architecture Description Element = any element allowed in a TRAK view)
- the Claim structure:
- Claim has part Claim
- Claim supports Claim
- Claim opposes Claim (to describe a counter-claim)
Structuring the Argument
The tuples that the TRAK metamodel provides to describe the Argument are:-
- Argument supports Claim
- Argument opposes Claim
- Argument has part Argument
- Argument supports Argument
- Argument opposes Argument (to describe a counter-Argument)
- Architecture Description Element traces to Argument ( to show where the structure or relationship is a result of an Argument made)
Identifying Supporting Evidence
The tuples that the TRAK metamodel provides to describe the Evidence are:-
- Evidence supports Argument
- Evidence opposes Argument
- Evidence has part Evidence
and then if the Claim - Argument - Evidence chain is accepted by the assurer or regulator this can be recorded using:
- Evidence proves Claim or
- Evidence disproves Claim
Note that the proves and disproves connectors both have attributes to record the assessment result and date of submission.
Applicable TRAK Architecture Viewpoints
The applicable TRAK architecture viewpoints are:-
- MVp-04 Assurance - to describe the claim, argument and evidence
- MVp-03 Requirements & Standards - to describe the normative requirements from specifications, contracts, statutes (and what they govern)