Separation of Concerns in Multi-agent Systems: An Empirical Study

Abstract

With multi-agent systems (MASs) growing in size and complexity, the separation of their concerns throughout the different development phases is crucial to MAS engineers. Separation of concerns is a well-known principle in software engineering to achieve improved reusability and maintainability of complex software. Hence it is necessary to investigate systematically whether abstractions from object-oriented (OO) software engineering are able to isolate explicitly MAS concerns. This paper presents an empirical study that evaluates the degree to which abstractions associated with two OO techniques enable modularization of MAS concerns. The selected techniques involve basic OO abstractions, such as classes and objects, and more sophisticated ones, namely design patterns and aspects. The gathered results shown that the use of aspects allowed the construction of a MAS with a significant improvement in the modularization of different concerns. Also, the use of aspects resulted in: (i) fewer lines of code, (ii) fewer design and implementation components, and (iii) lower coupling between the components. However, the aspect-oriented approach produced lower cohesion in the MAS components. Finally, an important finding of this empirical study is that aspects supported a better alignment with higher-level abstractions from agent-oriented design models.