UoL CS Notes
Menu

Requirements Engineering Process

COMP201 Lectures

This lecture is very similar to COMP107 - Requirement Elicitation.

The enginerring process goes as follows:

  1. Requirement elicitation - What services does the end-user require?
  2. Requirements analysis - How to we classify, prioritise and negotiate requirements?
  3. Requirements validation - Does the proposed system do what the users require?
  4. Requirements management - How do we manage the changes to the requirements document?

Feasibility Study

This decides whether the proposed system is worthwhile. It checks if:

  • The system contributes to organisational objectives.
  • The system can be engineered using current technology and within budget.
  • The system can be integrated with other systems that are used.
  • There is a simpler way of doing this.
    • Buy in software and customise.

Elicitation & Analysis

This involves the technical staff working with customers to find out the application domain, the services that the system should provide and the system’s operation constraints.

This will involve stakeholders such as:

  • End-users
  • Managers
  • Maintenance Engineers
  • Domain Experts
  • Trade Unions

These different stake holders will often have conflicting and non-specific requirements.

Requirements Discovery

This is the process of gathering information about the proposed and existing systems. These requirements often come from:

  • Similar systems.
  • Existing systems to be improved.
  • Competitor’s systems.

You can also discover requirements from prototypes.

Viewpoint Identification

Viewpoints are a way of structuring the requirements to represent the perspectives of different stakeholders.

Stakeholders may be classified under different viewpoints.

Interviewing

This involves the requirement elicitation team putting questions to stakeholders about the system. You can ask questions in the following ways:

  • Closed interviews - A predefined set of questions are answered.
  • Open interviews - There is no pre-defined agenda and a range of issues are explored with stakeholders.

Ethnography

This is the practice of observing workers in order to find out how they complete their work.

People don’t have to explain what they are doing.

Focused Ethnography

This is a combination of ethnography and prototyping. This may answer questions that may never have been asked.

There is an issue that you are studying existing practices which may no longer be relevant.