UML Designer User's Guide

Requirement

A requirement describes a function the system must perform in order to meet its fundamental business objectives. Requirements also help to define the boundaries of the system; some functions, though important, might turn out to be outside the scope of the system being developed. Requirements are formulated by the users of the system and describe what the system must do.

There are no strict rules governing what you can include as a requirement, nor what level of detail is appropriate. Indeed, the list is very likely to change over time, as you gain a better understanding of the problem domain and the system boundaries. You can use Requirement elements to capture any information that is useful for setting the system's objectives and that you want to capture for documentation and tracking purposes. Ideally, requirements should be short, succinct, and focused on the essential purpose of the system. Often, the requirement's title alone will suffice; other times, you might want to provide further explanation, which you can enter as hypertext.

A requirement should avoid any unnecessary descriptions of how the system will be implemented; instead, it should describe what the system must do for the user in order to work successfully. If you have quantifiable requirements that must be met, such as response times or scalability objectives, you can include these as well.


[ Top of Page | Previous Page | Next Page | Table of Contents | Index ]