A Rationale-based Model for Architecture Design Reasoning
A Rationale-based Model for Architecture Design Reasoning
A Rationale-based Model for Architecture Design Reasoning
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9.4. AREL and eAREL traceability applications in a case study<br />
elements in the AREL model. Enterprise Architect [150] is the UML design tool we use<br />
to capture the AREL model, the results of a trace are created as UML diagrams.<br />
Secondly, traceability can be selective <strong>based</strong> on architecture elements’ classifications.<br />
Using the classification of the architecture elements by viewpoints and business drivers (see<br />
Section 6.3), architects could limit the trace results to the specified types of architecture<br />
elements. For instance, a trace could traverse only those AEs that are specific to the<br />
data viewpoint. The classification-<strong>based</strong> traceability could reduce in<strong>for</strong>mation overload<br />
when analysing trace results. This is an initial attempt to implement the traceability<br />
scoping with classified architecture elements. It demonstrates that classification is useful<br />
in restricting the scope of the trace results.<br />
9.4 AREL and eAREL traceability applications in a case<br />
study<br />
Using the case study as a basis, we demonstrate the advantages of being able to explain<br />
and trace the architecture from the design reasoning perspective. It provides important<br />
in<strong>for</strong>mation that are missing from most design specifications in which the focus is on design<br />
organisation, interface and behaviour. In the demonstration, we choose the processing<br />
services and specifically the payment message processing layer to illustrate the rationale<strong>based</strong><br />
architecture model and its traceability below. We demonstrate the traceability<br />
with the AREL tool-set. The tool-set comprises of an UML-<strong>based</strong> tool called Enterprise<br />
Architect and a tool <strong>for</strong> AREL tracing. A detailed description of the tool implementation<br />
is in Chapter 11.<br />
9.4.1 <strong>Design</strong> rationale representation<br />
This section recapitulates an example from the case study in Chapter 7 to demonstrate the<br />
traceability techniques. The EFT system had extensive design specifications to document<br />
what had been designed. However, they do not systematically document the assumptions,<br />
constraints and rationale of the design. Its specifications document the design of the software<br />
modules, their interfaces and behaviour. <strong>Design</strong>ers who were not originally involved<br />
in the design would find it difficult to understand the design intentions. Thus, when system<br />
modifications are required, it would be hard to determine which parts of the system<br />
are affected. We use the payment messaging mechanism as an example to illustrate how<br />
a traceable AREL model captures this knowledge.<br />
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