Webel: SysML: SE: A functional analysis «whitebox» Activity may have swimlanes that Allocate to logical subsystems (logical handlers) within the 'problem' zone or to design/implementation level blocks.
SysMLv1: MagicDraw/Cameo: Having a SystemContext as the 'subject' of each main UseCase plays nicely with the feature for automated creation of usage-level allocation swimlanes in SysML Activity Diagrams for part properties. But it's not the only way.
SysMLv1: MagicDraw/Cameo: Automated creation of usage-level allocation swimlanes in SysML Activity Diagrams for part properties of a Block. EXAMPLE: A UseCase scenario within a SystemContext as UseCase ‘subject’.
SysMLv1: UseCase scenario representations: On use of Activity Diagrams with swimlanes and/or Sequence Diagrams (Interactions): Actor or block-based custom «actor» on 1st (typically left) Lifeline/Swimlane, System/Subsystem on 2nd Lifeline/Swimlane
Webel: MBSE: SysMLv1: Prefer a custom «actor» extension of a Block (such as the non-normative External) over UML-style Actor for use as parts in IBDs and on allocation swimlanes. You can also have a Trace from a block-based «actor» to a UML-style Actor.
