WORKERS IN REQUIREMENTS

How is all this translated concretely in terms of workers, artifacts, and activities? Figure 9-3 shows the main workers and artifacts in the requirements workflow:

Figure 9-3. Workers and artifacts in the requirements workflow

System Analyst

The System Analyst leads and coordinates requirements elicitation and use-case modeling by outlining the system's functionality and delimiting the system.
Use-Case Specifier

The Use-Case Specifier details all or part of the systems functionality by describing the requirements aspect of one or several use cases.
User -Interface Designer

The User-Interface Designer is responsible for selecting the set of use cases to demonstrate the essential interactions of the users with the system. Working with the users, the User-Interface Designer develops these into Use-Case Storyboards, and a User-Interface Prototype is developed to help determine the final requirements of the system.

Working with stakeholders of the project, the System Analyst analyzes the problem and works with stakeholders to understand what they need and to define what the system must do and perhaps what it should not do ”also identifying nonfunctional requirements. The System Analyst can then develop a vision for the project. This vision, expressed as a set of features written from the stakeholder's perspective, is a basis for developing an outline of a Use-Case Model.

The Use-Case Specifier is assigned a set of use cases and supplementary requirements, which he or she will detail and make consistent with other requirements workflow artifacts. The Use-Case Specifier does not work in isolation but rather should communicate regularly with other individual Use-Case Specifiers as well as with the System Analyst.

The User-Interface Designer works in parallel with the Use-Case Specifier to design the system's user interface. In most cases, there is a synergistic interaction between the two.

Another worker involved in the requirements workflow is the Architect, who is involved primarily in earlier iterations and works with the System Analyst and Use-Case Specifier to ensure the integrity of the architecturally significant use cases.

The Requirements Reviewer is another important role, representing all the different kinds of people you bring in to verify that the requirements are perceived and interpreted correctly by the development team. Because reviews have different purposes, they are performed several times during the execution of the requirements workflow by requirements reviewers with different profiles.

Together, the individuals acting as these workers form a team that exercises the requirements workflow iteratively throughout the project lifecycle.