SACM lacks display information for tool interchange
Source: Linux Foundation ( David A. Wheeler)
SACM provides an abstract model for information on assurance cases. However, most humans normally interact with assurance cases shown as diagrams with supporting text. SACM 2.1 finally adds a standard graphical notation, and I'm happy to see it.
However, SACM currently does not provide enough information to enable sharing diagrams in this notation. For example, there's no positioning or size information for displaying each ArgumentationElement in an ArgumentPackage. Tools do not always do a great job doing automatic layout, and in any case, humans often set up a layout to maximize human understanding. I believe this inability to exchange such information is a serious weakness in SACM.
There are many ways to include such information.
One way would be to require sharing display information in a standard form (like SVG) and provide a standard way to map between the SVG display information and the metamodel.
An alternative is to extend the metamodel to include display information. Some basic constructs from SVG could be borrowed (being maximally compatible with SVG in general is recommended). An ArgumentationElement could have a new optional "location" with contents min_x, min_y, width, and height per SVG. Each ArgumentPackage would establish a viewpoint (and essentially determine portrait, landscape, or some other display is preferred).
I'm sure there are many details to work out, but the first step is to agree that display information needs to be shared somehow.
Thank you for your time.
Reported: SACM 2.1 — Sat, 24 Oct 2020 19:06 GMT
Updated: Fri, 9 Apr 2021 12:30 GMT