Artifact: System Use-Case Activity Diagram
This artifact captures a specification of the functional flows for the system under development.
Domains: Systems Requirements
Purpose
To describe the functional flow for the system to validate and refine of the system requirements and to support architectural analysis and design.
Relationships
Description
Main Description

An Activity Diagram is similar to the classic flow chart. It describes a workflow, business process, or algorithm by decomposing the flow of execution into a set of actions and sub activities joined by transitions and various connectors. These actions and sub activities are called activity nodes. An activity can be a simple linear sequence of activity nodes or it can be a complex series of parallel activity nodes with conditional branching and concurrency.

There will be multiple instances of this artifact. During requirements analysis, "black-box" activity diagrams are created describing the functional flows for the system as a whole. During architectural design, "white-box" activity diagrams are created that show the allocation of actions to specific system elements.

Activities may be grouped and assigned to objects - e.g. subsystems. In this case, the activity diagram is split into swim lanes that depict the respective responsibilities.

Tailoring
Impact of not havingWithout this artifact it will be difficult to specify the required behavior of the system with the level of detail, completeness and clarity required to validate the development team's understanding of the required behavior and to communicate effectively.
Representation OptionsThis artifact is a UML/SysML artifact. There will be many activity diagrams that describe the system from different perspectives and with different levels of detail. They may be represented as reports or views from modeling tools or as diagrams in a document. The former provides additional confidence in the consistency of the information and is highly recommended.