Usage Models Flashcards
what is a usage model
describes the system behavior from the point of view of the user (“black box”) by modeling interaction sequences
The use cases specified in the usage model are derived from?
system vision
what is a use case?
a series of system events triggered by an actor that leads to results for the actor
what is a scenario?
an ordered set of interactions between partners, usually a system and a group of actors
3 parts of the usage model in AMDiRE
- use case overview diagram
- use case templates
- scenario diagrams
Use case overview diagram: interpretting the “includes” arrow
The use case (A) at the base of the arrow INCLUDES use case (B) at the tip of the arrow
in other words, performing use case B is part of performing use case A (A cannot exist independently of B)
Use case overview diagram: interpretting the “extends” arrow
The use case (A) at the base of the arrow EXTENDS use case (B) at the tip of the arrow
When use case A is performed you can optionally perform use case B
what is an activity diagram
shows high-level business processes, including data flow, or to model the logic of complex logic within the system
what is a sequence diagram
models the sequential logic and ordering of messages with respect to time