Model-based Systems Architecting

Introduction Systems

I.1. Systems from a pragmatic perspective

Let us first point out that we shall only be concerned with engineered systems in this book, that is, systems that are designed and constructed by people¹. As a result, the term “system” will only refer to engineered systems within the scope of this book.

Note that there are of course other objects – for instance, biological or natural systems – that may be considered as systems in an unformal meaning, but we shall not consider them in the perimeter of this book, which intends to focus on a methodological framework for architecting the systems that are developed by engineers. However, notice that engineered systems are not purely technological systems: organizational systems, such as a company or a city, which are a mix of technical systems and organized people, may also be considered to be the result of a voluntary design process and, thus, engineered systems.

From a pragmatic perspective, engineered systems can be classified in the following different types, depending on their level of integration, as described in Table I.1:

• – Product components, that is, systems that do not make sense independently of the product in which they are integrated: a typical example is an aircraft engine which only works within an aircraft. The classical design strategy for such systems is called the V-cycle: the system is first designed (the left-hand side of the V), then constructed (the bottom part of the V), before being finally ...