Metadata in the model
Models do not only contain the “real” artifacts for your system, but also additional auxiliary information like notes, issues, images, and so on (metadata). It is very useful to store such information at the place where you need or create it. Switching from one tool to another is a hurdle that prevents people from looking up things or creating ones. As a result many little deficiencies occur that lead in summary to less quality, more effort and costs.
My previous post Structure of a SysML model shows a scalable and easy to navigate package structure for a system model:
It is not a good idea to spread the metadata over the model. It is a different kind of information and should be separated from the exlicit system model artifacts. You can compare the metadata I am talking about in this post with the sticky yellow notes. Little helpful pieces of information, but you won’t store them persistently in your project documentation.
Therefore I propose to use special packages in the model to store the metadata. The packages are marked with an underscore to denote that special category:
The figure above shows three kind of metadata elements: issues, notes, and sketches. You can use your own set of elements. The issues and notes are SysML Comment elements. The sketches rely on a tool-specific feature to display and store images in the model.
Note that the package structure shows the location where the elements are stored in the repository. You can link the elements like an issue (=SysML comment) with any other element in your element and you can display it in any diagram.
The package structure with metadata is also described in the MBSE Cookbook.
Is this really “metadata”? Metadata is data about data, what’s being described here seems to me to be just more data. Auxiliary data maybe.
You are right. I wasn’t quite linguistically clean back then. I could probably talk my way out of it and interpret the word “meta” appropriately. But I would just call it “auxiliary” today, which is appropriate in any case.