Speaker: Paul Davies, Thesystemsengineer
Venues: Stockholm, Helsinki, Oslo
Interface Management is perceived as a critical skill in the engineering of successful systems, but finding useful material on the subject proves elusive. It is not that there is a gap in the collective Body of Knowledge (BoK)– but there is definitely still a gap in the documented BoK. This presentation explores some of the characteristics of this gap, and strings together some of the key concepts in best practice.
We start with a survey of what is documented. Mostly this is around “Standards” on how to structure interface documentation, but not how to get there. We also look at why the management of interfaces is logically different from that of system elements – double-endedness, integration criticality, non-linearity with scale, and traceability.
Next we look at why interfaces get neglected, invoking Douglas Adams’ “Somebody Else’s Problem Field.” The impact on architecting of retrofitting interfaces is explored, using a comparison of the usual System Breakdown Structure with, for example, James Martin’s Seven Samurai model. Along the way we note the multidisciplinary nature of interfaces in complex systems – it’s not just about software.
The key concepts of interface management are described, and logically chained together – the separation principle, black-box and white-box models, context diagrams, N2 charts, use cases & sequence diagrams, and phased integration pathways.
The use of interface analysis as an up-front tool in architecting, rather than as a capture mechanism for managing a physical design, is illustrated with several recurrent architecting problems.
We look at the lifecycle of interfaces, to support as-is, to-be and intermediate configuration states; extra sets to support the Deployment Concept, the Support Concept, and the Disposal Concept. We look at future-proofing of interfaces to systems yet to be implemented.
Finally we look at the strengths and weaknesses of document-centric versus model-centric interface management, and open the discussion out to the audience.