Architecture Modeling - SPES 2020

Architecture Modeling
Figure 5.14: Example for proving Allocation by Virtual Integration Test
the ports meterControl and meterValveStatus of the logical perspective are mapped
to the ports meterValve and valveStatus of the technical perspective. The components
of the technical perspective have a satisfy-link to the contracts C2.1-T1, C2.1-T2, C2.1-T3 and
C2.1.2-T3 where C2.1-T1 is relevant for MeterValveControl, C2.1-T2 for Channel and
both C2.1-T3 and C2.1.2-T3 for MeterValveActuator. The composition of these four
contracts has an entailment link to the contract C2.1 of the logical perspective that has to be
ensured.
To prove an allocation-link a virtual integration test may be performed as introduced in Section
4.2 consisting of the two steps of assuring compatibility and refinement.
Compatibility For the scenario from Figure 5.14, we start with the validation of the compatibility
of the three neighbouring components in the technical perspective or, to be more precise,
the compatibility of their annotated contracts. For this, we have to analyze their strong assumptions
and guarantees. Note, that the weak asspumptions do not constrain the compatibility of
systems. In this example, the second part of the guarantee of C2.1-T1 is compatible to the
second part of the strong assumption of C2.1-T2. The same holds for C2.1-T2 and C2.1-T3.
Further, in this example the assumption parts about the temperature do not influence the validity
of the composition of these three components because they are parts of interfaces to other
components.
Refinement As a further step, the entailment-link between the contract on the logical perspective
and the composition of the four contracts on the technical perspective has to be proven
to be a valid refinement. Checking the refinement for this example results in a falsification,
as the strong assumptions of the contracts C2.1-T2 and C2.1-T3 are stronger than the parent
contract C2.1. To be more precise, the assumptions about the temperature cannot be assured
by C2.1. To solve this situation there are at least two possible scenarios. One solution would
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