Military Communications and Information Technology: A Trusted ...

Chapter 1: Concepts and Solutions for Communications and Information Systems
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Figure 8. Example NSOV-2 Service Definitions
Services are described through well-defined interfaces. An interface definition
is an independent from the underlying platform on which a service implementation
operates. Fig. 8 shows an example service definition. Class diagram
with SoaML profile is used. The TargetMsgService provides two operations.
To implement its functionality the services ISTARService and ArtilleryService
are required. Fig. 7 describes the TargetMsgService behavior and depicts how
the required services are used.
A service is a concept which represents well defined fragment of an operational
functionality so it is at a level above the technology details. Each
functionality described by a service is implemented by software components or
legacy systems which are responsible for quality of those services. Fig. 9 describes
the software components as well as the provided and required service interfaces.
The ISTARComponent is an adapter to the legacy system (ISTARSystem) and
implements the service defined by the ISTARService interface.
A component implements a set of operations. The behavior of methods describes
scenario and can be specified using interaction diagrams. Fig. 10 presents
the specification of the example method. Furthermore, methods have demands
for resources which is modeled using MARTE profile. Requests which consume
resources are modeled using the PaStep stereotype, while communicates send
by network are stereotyped using the PaCommStep.
Figure 9. Example NSV-12 Service Provision