Extension use cases description

An extension use case includes a Title as previously defined, and one ore more parts. These parts are to be inserted at specific extension points in a base use case.

A part includes:

• a reference to an extension point (defined in a base use case in reference to a step), and
• a sequence of steps defined as previously with the difference that extension use cases cannot include extension points.

Log in secure extends use case Log in such that information provided by a user logging in is recorded.

Figure 4.3: Extension use case.

Title:

Log in secure

Parts:

At extension point card inserted

1:

System logs transaction

At extension point pin entered

1:

System logs transaction

This extension use case includes two parts. One to be included at the extension point ``card inserted'' and the other at the extension point ``pin entered''.