Software Development for Modeling and Simulation of Computer Networks: Complex Systems Approach

The process of creating software for modeling and simulation of phenomena taking place in computer networks should take into account many aspects of their functioning. However, until now, the creation of such software was based on a reductionist approach. This approach is typical for simple or most complicated systems. In contrast, software for modeling and simulation of computer networks should be treated as a complex system. Therefore, the process of its creation should take into account such properties of complex systems as: feedback loop, non-extensivity, indeterminacy, self-similarity, non-additivity, etc. The authors use computer simulators in their work on everyday basis. However, they have generally an outdated, static architecture that prevents their easy and continuous development. Therefore, the authors started working on developing their own model of creating such software and this paper is an introduction to this issue. The authors focused on the selected features of complex systems in the context of the software development process. Based on the feedback loop, a new spiral of software development and modeling for computer networks is presented. The paper also defines the notion of process and functional non-additivity and its importance in the software development process. The presented approach allows for flexible development of the software under consideration in terms of their functionality. The authors also presented examples of application of complex system properties when creating selected functional modules of software for modeling and simulation of computer networks.