Conceptualization of a System-of-Systems in the Defense Domain: An Experience Report in the Brazilian Scenario

National sovereignty and protection require a diversity of interdependent systems that jointly provide a large infrastructure for the national security, making possible a continuous monitoring and control. These systems assure the confidential information exchange while providing more complex functionalities when working together and forming alliances known as Systems-of-Systems (SoS). This paper reports an experience in the Brazilian defense scenario, externalizing the acquired knowledge in the form of lessons learned during the conduction of a real, strategic project called SisGAAz (Blue Amazon Management System), which has its main goal to develop the Brazilian navy management SoS. In particular, we focus on reporting our experience in the architectural design of this SoS as a quality driver in our project. We also raise challenges that were overcome, and also others that must still be faced. The results communicated herein contribute to deliver a panorama of the Brazilian state of the practice about SoS engineering. Such results are important, as they report the current situation and gaps to be bridged by both academics and practitioners, not only in Brazil but also worldwide, especially in those developing countries that are also living and implementing such technological revolution.