Architecture Modeling - SPES 2020

Architecture Modeling
refined by decomposition of components (see Section 3.3.2.2), but also by means of a different
component hierarchy. So refinement subsumes but is not restricted to simple decomposition of
components. When switching abstraction levels the component-models must be related to each
other. This is done by Realize-trace links (shown in Figure 3.2), that constitute a mapping
relation between component instance roles of different abstraction levels. Due to its similarity
to Allocate-trace links, the superordinate concept of Mapping has been defined, that is
discussed in Section 3.4.
+type 1
RichComponent
+component 1
«isOfT ype»
+part 0..*
+m appedT o
RichComponentProperty
1 «instanceRef»
+m apped
1
«instanceRef»
Allocate
Mapping
Realize
Figure 3.2: Meta-model integration of the concept of Realize-trace links
While the models on lower abstraction levels usually provide more detail with regard to the
design item, the respective models still have to satisfy all functional and non-functional requirements
defined for their higher level counterparts with respect to a continuous development
process. The Realize-link provided by the meta-model also indicates the proof obligations,
that have to be performed to ensure a valid refinement with regard to the specified contracts.
The realize relation is discussed detailed in Section 4.4.
Since the design processes for different application domains like automotive and avionics are
very diverse, a fixed set of predefined abstraction levels has found to be insufficient to support
different domains. The EAST-ADL abstraction levels for example are just one possible instantiation
of the generic abstraction level concept. In other application domains, e. g. avionics, or
even for different companies in the same domain, the set of actually used concrete abstraction
levels may be different. The meta-model provides concepts for tailoring models to specific
needs. This allows to define so-called model libraries that provide predefined sets of abtraction
levels, such as those defined in EAST-ADL. The underlying formal semantics of the Realizelink
then allows the verfication of refinements of component-models.
3.2 Perspectives
Beside the distinction of different user-defined abstraction levels, a model of a system under development
may be associated with certain viewpoints, such as defined in [33]. The architecture
meta-model differentiates between viewpoints that establish structurally different views on the
system (perspectives), and viewpoints, that are orthogonal to the structure of the system and describe
different aspects of functional and/or non-functional properties of model elements. The
concept of aspects is discussed in Section 3.3.1.2.
So models of a system addressing a certain perspective will specify the structure of the system
from that particular perspective. This results in a two-dimensional organization of component
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