(Last modified Wed Nov 07 12:46 2007)
i* is an approach developed by Eric Yu and John Mylopoulos for modelling the organizational context of a software system. Recent work with i* has been done by Neil Maiden and others.
Figure 1. i* diagram key
The nodes and edges in i* diagrams appear in Figure 1.
| Source node | Edge | Destination node |
|---|---|---|
| goal, task | means-end | goal, soft goal |
| resource | means-end | soft goal |
| soft goal | contribute-to (+ or −) | soft goal |
A strategic dependency diagram relates actors with needs (“dependers”) to actors with the capability of meeting those needs (“dependees”). The relations are expressed with dependency edges. The needs are expressed in terms of goals. Yu and Mylopoulos use “dependum” to refer to what is needed.
A strategic rationale diagram describes how actors may achieve goals through tasks. Subtasks are linked to their supertask by task-decomposition edges. Alternative ways of accomplishing a task are linked to the tasks by means-end edges. Subgoals are linked to the goal they help achieve by contribute-to edges.
The i* wiki.
