A Rationale-based Model for Architecture Design Reasoning

3.3. Existing methods for capturing and representing design rationale
• Detecting Reasoning Inconsistencies of Design Decisions - in one study, a tool called
SEURAT was built to verify the consistency and completeness of the design rationalisation
[14]. This could help maintainer trace design rationale and identify any
reasoning gaps in the design for maintenance purposes.
Even though design rationale have many uses in supporting the design and maintenance
processes, capturing design rationale is still uncommon. It was suggested that the lack of
short-term payoffs might be one of the causes [24]. Another reason was that the tools and
the methods used in design rationale capture are not closely aligned with existing design
processes therefore resulting in higher cost of design rationale capture [24]. In the following
sections, we will examine some of the design rationale methods, the tools availability and
their potential benefits and drawbacks.
3.3 Existing methods for capturing and representing design
rationale
A simple explanation of design rationale is the explicit representation of the design reasoning.
There are other different aspects of design reasoning. A design reason could be
an intention to motivate the creation of a design artefact. It could also be a constraint or
an assumption that influence a design artefact, a tradeoff between requirements, a judgement
to select from a number of design options and an argument for or against a design
proposition.
There are different approaches to design reasoning. One approach is by way of argumentation.
The basic argumentation-based representation is to use nodes and links to
represent knowledge and relationships. It dates back to Toulmin’s argumentation representation
using datums, claims, warrants, backings and rebuttals [168]. In Toulmin’s schema,
examples of a node are a datum or a claim, which represent an observation and a conclusion
respectively. A link type such as “so” can be used to connect the nodes to show the
inductive relationship. Since Toulmin, many similar argumentation-based approaches such
as Issue-Based Information System (IBIS) [87] and Design Rationale Language (DRL) [92]
have been invented. They fundamentally show the issue, the argument and the resolution
of design argumentation.
A different approach to capturing design rationale is to use template-based methodologies.
These methods make use of standard templates which is incorporated into the design
process to facilitate design rationale capture. Contrary to argumentation-based methods,
practitioners using the template-based methods do not construct argumentation diagrams
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