System- and Software-level Architecting Harmonization Practices for Systems-of-Systems -- An exploratory case study on a long-running large-scale scientific instrument

TL;DR

This case study explores how practitioners address the gap between system and software architecting in large-scale scientific instruments, highlighting best practices, challenges, and benefits in a real-world context.

Contribution

It provides empirical insights into architecting practices for Systems of Systems, emphasizing the importance of dedicated roles and unified standards based on practitioner experiences.

Findings

Need to avoid over-reliance on software flexibility

Importance of early system architecting involvement

Benefits of dedicated architecting roles and standards

Abstract

The problems caused by the gap between system- and software-level architecting practices, especially in the context of Systems of Systems where the two disciplines inexorably meet, is a well known issue with a disappointingly low amount of works in the literature dedicated to it. At the same time, organizations working on Systems of Systems have been developing solutions for closing this gap for many years now. This work aims to extract such knowledge from practitioners by studying the case of a large-scale scientific instrument, a geographically distributed radio telescope to be more specific, developed as a sequence of projects during the last two decades. As the means for collecting data for this study we combine online interviews with a virtual focus group of practitioners from the organization responsible for building the instrument. Through this process, we identify persisting problems and the best practices that have been developed to deal with them, together with the perceived benefits and drawbacks of applying the latter in practice. Some of our major findings include the need to avoid over-reliance on the flexibility of software to compensate for incomplete requirements, hidden assumptions, as well as late involvement of system architecting, and to facilitate the cooperation between the involved disciplines through dedicated architecting roles and the adoption of unifying practices and standards.