Webel: SysML-1.7/SysMLv2: WISHLIST: Constraint: A BindingConnector used for pure proxying MUST NOT be typed by an AssociationBlock by definition, because the associated information can be mis-appropriated to undermine the proxy equality!

Icon class
icon_class
far fa-sticky-note
icon_class_computed
far fa-sticky-note
Note kind
CONSTRAINT
PROPOSAL
WISHLIST
Policy level
STRICT
Specification keywords
SysML-1.7
SysMLv2
SysMLv1.x keywords
SysMLv2
AssociationBlock
BindingConnector
ProxyPort
Keywords
Click on the image to view it full size
The attached image illustrates the potential issue. An AssociationBlock used to type BindingConnector can be used to undermine a pure proxy; in this case, some L and R stereo channels have been swapped.

According to this Webel Best Practice policy, the use of an AssociationBlock to type a Connector (any Connector) is a declaration that you are NOT simply proxying.

Pro: Excluding AssociationBlock as a possible type of a BindingConnector used for ProxyPort delegation also helps you know when it is NOT proxying .

AssocationBlocks are cool! Just please don't use them on a true proxy connector.

The diagrams also show another potential issue that can arise when using an AssociationBlock this way with nested ports; the tool will report that the direction is invalid on the inner Connectors (thanks to John Brush of 7Sigma for identifying this concern and for discussions).

To see a better way of modelling a jack or socket that avoids these issues please visit: Webel: SysML: Electronics: DO NOT represent a jack/socket as a dumb proxy. Imagine it can introduce some signal noise or other effect (such as buzz) to test it is a physical model.

Relates to
Related notes
[ANTI-PATTERN, MODELLING, PATTERN, TIP]{STRONG} Webel: SysML: Electronics: DO NOT represent a jack/socket as a dumb proxy. Imagine it can introduce some signal noise or other effect (such as buzz) to test it is a physical model.
Related notes (backlinks)
Related snippets (extracts)
  [SysML-1.6] A Binding Connector is a connector which specifies that the properties at both ends of the connector have equal values.
  [SysML-1.6] A Binding Connector is a connector which specifies that the properties at both ends of the connector have equal values.
  [SysML-1.6] If the properties at the ends of a binding connector are typed by a ValueType, the connector specifies that the instances of the properties shall hold equal values, recursively through any nested properties within the connected properties.
  [SysML-1.6] If the properties at the ends of a binding connector are typed by a Block, the connector specifies that the instances of the properties shall refer to the same block instance.
Visit also
Visit also (backlinks)