Web Engineering Models and Requirements Capture Methods

Web Engineering Models

Data Model

Compatible with the entity-relationship model and UML class diagrams.

Hypertext Model

• Composition: Site pages, content units of pages.
• Unit: Atomic content element, used to publish the information specified in data models.
• Navigation: Specified by links.
• Links: Between units of a page, between units of different pages, or between pages.
• Defines both the content and navigation.

Presentation Model

• The appearance of web pages.
• Does not include specific elements for conceptual modeling; notations are used.
• XML.
• The presentation is specified using XSL stylesheets.

Web Engineering UML-Based Methodology (UWE)

• Proposal based on UML and the Unified Process, adapted to the web.
• Specific object-oriented techniques are used.
• Proposes an iterative approach to development.
• UML notations, techniques, and UML extension mechanisms (stereotypes) are used.
• Nodes: Classes.
• Links.
• Indices: Stereotypical associations, navigation maps: stereotyped classes.
• Modeling Dynamic Aspects: Task models, state diagrams, sequence diagrams.

Requirements Capture Techniques

Interviews

• Natural approach to the problem.
• Simple? No!
• Experience and skills are required.
• Specific interviews are extremely important!

Joint Application Development (JAD)

• Joint development of applications.
• Group technique, developed over several days.
• Participants: Analysts, managers, customers, users.
• Principles: Group dynamics, use of visual aids, organized process, WYSIWYG documentation.
• For each session, requirements, the scope of the problem, and documentation are set.
• Each session ends with documented conclusions!

Brainstorming

• More easily facilitated than JAD.
• Does not require as much preparation.
• Less controlled group, but moderated.
• Good for an overview, not for establishing needs in detail.

Concept Mapping

• Graphs that represent concepts and relationships between them.
• Easy to understand for users.
• Can be ambiguous.

Sketches and Storyboards

• Drawings that may be grouped and joined together by links.
• Used to give an idea of the navigational structure.

Use Cases

• Easy to understand for customers (and users).

Questionnaire and Checklist

• Document with questions whose answers are short and clear.
• Questions with closed answers.
• Used to supplement interviews or independently.

Comparison of Terminology

• To obtain consensus on terminology.
• Requires identifying correspondences, conflicts, and contrasts.