The Role of Interfaces in Enabling Transformational Systems Engineering

Years ago, Eberhardt Rechtin and Mark Maier observed that “the greatest leverage in [systems] architecting is at the interfaces,” meaning that interfaces are the key to managing complexity and reusing existing entities in a new or revised system. The extension of this observation is that interfaces are also the greatest leverage in the systems development process itself, thus permitting customization of these processes to the unique aspects of the system‐to‐be. Instead of tailoring down a single monolithic systems development process, it may be more advantageous to constructively define a custom process by connecting the defined interfaces of development practices. Evolving systems development methods such as agile systems engineering and design thinking provides a pallet of practices for augmenting or hybridizing classical systems engineering. However effectively aggregating these practices into a cohesive and effective method presents its own set of challenges. A “plug and play” approach to combining methods is a conceptually attractive approach to the challenge of effectively combining practices. However, past experience shows that engineering plug and play architecture for custom systems development is not a trivial process and requires careful design of the interfaces supporting the interconnecting of parts into a useful whole. To enable “fully digital systems development,” these interfaces must also be well‐defined and realizable by engineering tools — abstract and conceptual process definitions will not support this concept. This paper examines the role of interfaces in leveraging existing or new systems development practices and outlines the activities and challenges associated with this undertaking.