A Rationale-based Model for Architecture Design Reasoning

10.3. Reasoning about change impact with AREL
10.3 Reasoning about change impact with AREL
10.3.1 An example
In this section, we build on the example of designing the message processing module
to illustrate how to use quantifiable change impact analysis with BBN. This example is
explained in the case study in Section 7.1.3. As discussed previously, one of the key
issues in payment messaging design is to optimise its performance, and a key factor is
whether payment messages are processed synchronously or asynchronously. In this case,
asynchronous messaging was selected and a chain of architecture design decisions and
design objects were formed (see Figure 10.3). When considering the payment messaging
design, security issues such as authenticity and privacy must be considered as well. It is
because security features could influence the software architecture, especially in the areas
of exception handling and acknowledgement processing. In the following, we will consider
the payment messaging design together with its security features.
Figure 10.3: Payment Messaging Design: Asynchronous Message Processing
Payment messages are transmitted over different networks and some parts of those
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