SYSPHS12 — Suggest BDDs should use explicit SysML Ports shown in compartments on Blocks instead of an apparently user-defined «port» keyword on Association ends

Throughout the spec many (not all) BDDs show Association ends with an apparently user-defined «port» keyword defined. It is not made clear in some cases whether this is applied to a Port OR a Property (to indicate it's being used as a "port"). This reporter (who is otherwise quite a fan of the associative graphical approach for some modelling tasks and audiences) recommends that this diagramming approach be removed and replaced with simple listing of Ports in compartments of Blocks, which makes it absolutely clear that Ports are used.

There are many examples of use of this user-defined «port» keyword in Annex A such as:

• BDD: Figure 39: Electrical blocks, ports & component properties

• BDD: Figure 49: Total system (source to sink) blocks, ports, & component properties

The corresponding IBDs don't show (or need) the «port» keyword anyway:

• IBD: Figure 47: Internal structure of test bed from signal source to sink

There seem to be some other inconsistent cases. For example, on p. 38 in PD Figure 25: Constraint block for signal flow in SysML it appears to show the u.sig and y.sig (should BTW be u.rSig and y.Sig) as Property symbols with SysML property-path dot notation, rather than as Port symbols on the block boundary. There is no exact corresponding BDD, but it's inconsistent compared with Figure 23: Ports for physical interaction in SysML on p.31, which just using a Ports compartment on a Block.

This issue has also been identified in the SysML-1.6 spec under SYSML17-351 If there is no «port» keyword in UML-2.5.1 or SysML-1.6 it should be removed from Figure 9-8