The status of diagrams in the RA

[Francis McCabe <fmccabe@gmail.com>]

I noticed, belatedly, an issue wrt our diagrams in the specification.

We do not state whether or not the diagrams are 'normative'. 
In the RM, diagrams were definitely not normative.

We have two possibilities:
1. The diagrams are not normative. 
In this case, the text SHOULD 'stand' without the diagrams. It does not. There are many diagrams, esp. in S4, where the diagrams are not fully backed by verbal descriptions.
This represents a massive amount of work to fix.

2. The diagrams are normative.
In this case, we need to make sure that the diagrams are accurate, complete and consistent. Again, there are substantial areas (esp. in S3 and S5) where this is not true.
In addition, we need to state clearly that diagrams are normative; and we need to establish the 'rules' for interpreting the diagrams together with the text.
In fact, I believe that the only way to ensure consistency is to repeat the exercise of constructing a single large model of the entire architecture.
This represents a large amount of work to fix.

Personally, I think that we SHOULD make the diagrams normative. The use of UML suggests that they are.

Frank