Waiting Phase
It is sometimes useful to conceptually split the acquisition phase into its two constituting sub-phases. When this has to be done, the first sub-phase is called the waiting phase, while the second sub-phase keeps the name of acquisition phase.
Two additional events are introduced to account for the waiting phase:
- SWP is a shortcut for the event marking the beginning of the waiting phase (Start of Waiting Phase)
- EWP is a shortcut for the event marking the end of the waiting phase (End of Waiting Phase)
The above drawing suggests that the EWP event unconditionally provokes the SAP event.
The reason for introducing the waiting phase concept is the functional requirement for a waiting sub-phase starting before the end of the previous acquisition sub-phase.
The above drawing shows that the definition of the acquisition phase as an interruptible amount of time is maintained despite the occurrence of the starting event SWP during the acquisition phase tenure.
This functional requirement is called phase overlapping.
Note. The waiting phase events EWP and SWP are not available. They will be added in a future release.