Requirements Modelling

Use case diagram:

Features:

• Top-level description of system functionality
• Understandable by non-IT.

Components:

• Actors
• Use Cases
  • Described as imperative sentences.
  • Linked to a single actor.

Extensions

Inclusion

• include executing A always includes B

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Example:

Extension

• Executing A could include B

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Example:

Generalization

• Every campaign manager is a staff member
• Not every staff member is a campaign manager.

Guidelines

• include and extend are used to indicate that executing one system function is / can be part of executing another system function.

• include and extend are not used to describe casual relations between use cases.

• Casual relations should be part of a process model (activity diagram) not a functional model (use case diagram).

• A use case describes one (set of) interactions with the system, in a limited time frame

Use Case Model

A use case model extends a use case diagram to:

• show that the requirements are met by the proposed use cases.
• correctly interpret the diagram.

Components

• Glossary
• Requirements list
• Actor list
• Use case diagram
• Use case descriptions (short)
• Use case descriptions (extended)

Glossary

Term	Description

Requirements list

Nr	Requirement	Use cases

Actor list

Actor	Description

Use case diagram

see example above

Use case descriptions (short)

Use case	Description

Use case description (extended)

Use case description: x

Actor Action	System Response
1	2