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Architecture Modeling - SPES 2020

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<strong>Architecture</strong> <strong>Modeling</strong><br />

The semantics of HRC is defined such that behavior is always part of a RichComponent or<br />

specializations thereof. The connection of ports (syntactically described in Section 3.3.2.2) is<br />

semantically interpreted as the identity of the behavior observable at the connected ports. So if<br />

in the example sketched in Figure 3.8 the ports p1 and p2 would have been directly connected,<br />

then any event or data occuring at port p1 is at the same time observed at port p2. Thus, in<br />

order to be able to specify assumptions about communication latencies from a real-time aspect,<br />

one needs at least conceptionally a LogicalComponent. For that component contracts can<br />

again be used for the specification of the different aspects of the logical communication, e. g.<br />

expected latencies or failure hypothesis. Though conceptionally logical communcation has to<br />

be represented as a RichComponent, the user-representation can be different. For example<br />

a UML-profile based on the architecture meta-model, can introduce a stereotype, which is<br />

applicable to uml::Connector and is mapped to the concept of LogicalComponent.<br />

3.2.4 Technical Perspective<br />

In the technical perspective the electric/electronic architecture of the system is specified, which<br />

comprises mechanical and hydraulic components controlled by a network of control units, that<br />

the logical components shall be allocated to. The electronic control units may be softwareprogrammable<br />

hardware components or application specific integrated circuits (ASICs). Mechanical<br />

components are for example cams, shafts, switches and relays. Hydraulic components<br />

include for example valves and cylinders.<br />

The concepts provided for describing a view corresponding to the technical perspective are<br />

more specialized than those provided for modeling an operational, functional or logical perspective.<br />

That is because it is intended to apply dedicated analysis techniques for checking<br />

satisfaction of contracts (cf. Section 4.3) based on models of the technical perspective. In Section<br />

5.1.3.5 an example is presented how the concepts described in this section can be used to<br />

model a technical view.<br />

+part 0..*<br />

RichComponentProperty<br />

«isOfType»<br />

+component 1<br />

+type<br />

1<br />

RichComponent<br />

TechnicalComponent<br />

+aspect<br />

SystemArtefact Aspect<br />

Requirement<br />

+ rationale: String [0..*]<br />

SystemRequirement<br />

0..*<br />

+stakeholder<br />

0..*<br />

Stakeholder<br />

Figure 3.9: Meta-model integration of the concepts of TechnicalComponents<br />

The architecture meta-model provides concepts to specify the technical perspective of a system<br />

by means of TechnicalComponents (see Figure 3.9). While we do not provide specialized<br />

concepts in the meta-model for mechanical or hydraulic components, their aspects however<br />

can still be specified by means of contracts. That allows a characterization of their dynamics<br />

and to assess whether requirements on functions are fulfilled by the mechanical or hydraulic<br />

components and the electronic components controlling them.<br />

In <strong>SPES</strong> the focus is on software-intensive systems. Therefore the meta-model incorporates<br />

specialized concepts to describe the resources of a network of electronic control units, which<br />

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