Summary
This quite long chapter showed how a formalized diagramming technique can be used to obtain a better understanding of an information system and also document the evolutions it will have to follow. A map is a prerequisite to control a given ground, and a schema is worth a thousand words, which makes this step a must in any information system architecture activity.
Since IT is quite a specific context, we needed a dedicated way of drawing a map of an information system, and this is what the CIGREF map is about. Its four-layer arrangement helps separate the business-oriented aspects (processes and atomic functions) from the technical aspects (software and hardware).
This way of representing an information system also helps in visualizing its alignment, by checking that the third layer (the software bits) is well adjusted to the second layer (the business capability map) it implements. The business/IT alignment is the most important measure of quality and capacity to evolve...