Using Nesting in Archimate is a concise and aesthetically pleasing shorthand way of representing relationships between entities
http://pubs.opengroup.org/architecture/archimate2-doc/chap07.html
However the relationships aren't modelled in EA, instead the object simple comes 'in' the other object which has no meaning in ArchiMate.
Is the support for proper nesting relationships in ArchiMate on the roadmap for EA? If so, when are they expected, if not can they be added?
I use the term
embedding rather than nesting - since nesting (especially in a browser sense) has implications for namespaces and object access).
Visually embedding one object inside the other DOES NOT imply nesting the object under the other (for example, in the browser). You can only be nested under
one object, yet you can be visually embedded within a number.
As the Standard implies, visual embedding is an expression of an underlying relationship between the "outside" item and the "inside" item(s). The Standard, correctly, says a number of relationship types can participate in this "grouping", Aggregation, Composition etc. The set of items in the grouping is a "thing" in itself.
We've combined the concept of ArchiMate Grouping and Specialization Sets (the correct name for UML Generalization Sets). To materialize the grouping as an object in the repository and generate linkages to the various participants to formally manage and render (we think) all the necessary aspects of the visual embedding paradigm.
We allow Specialization Sets, Aggregation Sets, Composition Sets, Association Sets and (from memory) Assignment Sets.
In other words, you need to collect more metadata than you have available when you (simply) visually embed in order to correctly model what is happening.
With or system, we can:
- make relationships attach to the Set object, imlying that it applies to all items within the grouping
- indicate whether the grouping is "covering", "disjoint", and its cardinality. So you can know when looking at a diagram whether you are seeing the complete set of items related under than grouping in THAT diagram. That is: "Am I seeing the full story or not?"
We do all this by creating our own MDG specifying new metatypes and shapescripts (and Quicklinker).
HTH,
Paolo
