Architecture Modeling - SPES 2020

Glossary
Architecture Modeling
System under development (SuD) The notion system under development denotes the software
intensive system on a defined abstraction level. A system under development may
involve various perspectives(↑).
Architecture An architecture describes the basic structure of the system under development(↑).
Component A component is self-contained and provides functions of a system. It has a well
defined interface. Typically a component itself consists of a set of parts(↑).
Ports Ports specify the interface of a component(↑). A port can either define a data-oriented or
a service-oriented interaction point. Further, ports have a direction and are either input or
output ports or bidirectional. A port is typed by a specification describing a set of flows
or services needed or offered by a port.
Part Parts are sub-components in the context of an encompassing component(↑). The concept
of parts enables the hierarchical structuring of components(↑).
Heterogeneous Rich Component (HRC) Heterogeneous Rich Components extend the concept
of components(↑): The term rich refers to the fact that a component can have
an aspect-specific specification and realization. Heterogeneous means that different
aspects(↑) typically use different modeling elements.
So, an aspect specification defines what a component should do and a realization defines
how the component actually behaves. Specifications in the context of SPES are done by
means of contracts(↑). The realization of a certain aspect of a component can be modelled
by any other formalism.
Contract Contracts give the specification of a component and formalize system-requirements.
This enables model based analysis techniques. Syntactically a contract consists of a
strong assumption, a weak assumption and a guarantee. The strong assumptions specify
the allowed design context. If a component is used outside this specification, product
liability does not apply. In contrast to this, the weak assumptions define different possible
system contexts. A single weak assumption defines a part of the allowed design context.
The guarantee specifies the behaviour guaranteed by the component, if it is used in the
allowed system context, i.e., its strong assumption does hold.
Requirement Specification Language (RSL) RSL is a pattern-based language which can be
used to formalize properties of design items. With RSL it is possible to capture
contracts(↑). For this, one RSL-expression is used to specify the strong assumption,
the weak assumption and the guarantee respectively.
Abstraction Level An abstraction level provides a specific level of description and analysis of
a design item (e.g. component). On the next lower abstraction level the granularity of the
design item is refined. Such a lower abstraction level is realized by specific decomposition
techniques. Models on different abstraction levels may differ in both their granularity and
their viewpoints(↑). Realize links(↑) between models allow to trace those refinements.
The use of abstraction layers may support both the reuse of solutions and the management
of the supply chain.
Note that components of models on lower abstraction levels still have to respect the aspect
specifications(↑) defined for their higher level counterparts.
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