Architecture Modeling - SPES 2020

Architecture Modeling
a specific sensor measuring temperature or a computing device (e. g. ECU or IMA module)
hosting software applications.
The generic concept of components is extended resulting in so called Heterogeneous Rich
Components (HRC)(↑). Per aspect these HRCs have a specification as well as a realization (cf.
Section 2.3.1.2). Figure 2.5 depicts those fundamental principles of an HRC. Per aspect it has
specifications of its behavior with respect to that aspect. Optionally an aspect realization of the
component is given. Parts of the behavior are exposed at the ports(↑) of the component.
2.3.1.1 Ports
Ports(↑) are the interaction points of a component. Together with their types they define the
syntactical interface of the component. A port can either define a data-oriented interaction
point or service-oriented interaction point. Further, they have a direction and are either input
port (sometimes called required ports), output ports (provided ports) or bidirectional.
p1:PortSpec1
p2:PortSpec2
Component
f1
f2
f3
PortSpec1
Flow
PortSpec2
s1(param,...):return
s2(param,...):return
Service
Figure 2.6: Typing of Ports
A port has a name and is typed by a port specification as illustrated in Figure 2.6. That
specification is a set of flows or a set of services. A flow also has a name and is typed by a
datatype like for example int. A Service has a name as well and is declared by its parameters
and return type.
2.3.1.2 Aspects
A view modeled by an HRC may address different aspects(↑). The concept of aspects classifies
descriptions of the dynamic behavior of an HRC. Though being extensible by user-defined
aspects, we currently consider three pre-defined aspects: functional behavior, real-time and
safety. The functional behavior aspect of an HRC characterizes its dynamics by relating events
to each other and describing the handling of conditions and invariants. The real-time aspect
of an HRC defines the timings of its functional behavior, such as assumed activation behavior
(e.g periodic with jitter) or end-to-end deadlines of chains of functions. The real-time aspect
usually abstracts from actual values received or sent at the ports of an HRC, but focusses on
the timing of events instead. The safety aspect of an HRC provides specification of single point
of failures, as well as failure conditions and hazards. This also encompasses probabilities for
the occurrence of failure conditions. Thus aspect specifications describe functional and nonfunctional
characteristics of an HRC.
For each aspect of an HRC there can be a specification and an aspect realization. A specification
of an aspect of an HRC is a characterization of the realization of the HRC with regard to
the aspect. That means an aspect specification defines ”what” an HRC does, while a realization
describes ”how” it does that. Specifications are done by means of so called contracts(↑). The
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