The OIAm workflow
OIAm uses a distinctive workflow for infrastructure creation, that was inspired by the work of Gerrit Blaauw (see text box below). This workflow is characterized by three separate steps or stages. • a functional stage, where generic functional models are translated into applied functional models, using stakeholder requirements as input, and delivering functional models and sets of architecture requirements as output; • a technical stage, where generic technical models is translated into applied technical designs, using the architecture requirements and functional models as input, and delivering design specifications and construction models as output; • a realization stage, where generic construction components are translated into specific constructions, using the design specifications and construction models as input, and delivering the actual constructions with their configuration as output. In each of the three stages, there is a movement from archetypical or generic models towards applied, more specific models, by which the archetypical model is specialized so that it fits optimally within the target context.
Early in the 1960s, Gerrit A Blaauw worked with Fred Brooks and Gene Amdahl on the IBM s/360 mainframe. This not only led to some influential new features (such as fixed length 8-bit byte, 32-bit word, and the EBCDIC character set), but also to a new view on the development of IT systems, that Blaauw outlined in a paper[1] as far back as 1972. In this paper, Blaauw proposed to subdivide the design process of a computer system in three distinct stages, which he called architecture, implementation, and realization. Blaauw illustrated these design stages with the example of an (analogue) clock.
When developing OIAm, we built on the ideas of Blaauw to suit the intricacies of modern infrastructure, and derived a version of Blaauw’s three step approach geared to infrastructure creation. The three steps are outlined summarily in the following. Note that the first two steps have been relabelled from Blaauw’s original terms ("architecture" and "implementation"), to prevent misconceptions that the original names could raise.
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