XML for Structured Requirements

Simon Ambler.

Version: 0.1
Date: 6th October 2002

Introduction

Documentation based on the DTD.

Elements which are not described below may be found in Common XML for Requirements and Solutions.

See also XML for Structured Solutions.

XML elements

<requirements> The document root element.

Contents: (title, author+, introduction?, (function | quality | resource)*)

Attribute Sort Value Description
date required text Date of release.
version required text Version number for identification.
solutions optional Text The URL of the corresponding solutions document (with .html extension).

<function> A single function or a combination of functions which might be grouped together as an area of functionality within the system.

Contents: (summary, details?, (function | quality | resource)*)

Attribute Sort Value Description
tag required text Brief tag to identify the element in the hierarchy.
stake-holder optional text The source of this requirement (either an individual person, or an interested group).
date optional text The date that this requirement was added to the specification.
importance optional (critical | high | medium | low) The extent to which failure to meet this requirement would impact on the project as a whole. In particular, failure to meet a critical requirement would spell disaster for the project.

<quality> Some indicator of how well the system performs a particular function.

Contents: (summary, details?, scale?, test?, current?, worst?, plan?, best?, quality*)

Quality is always measurable. A quality element may correspond to a single measurable aspect of the system, in which case it can be measured directly; or it may correspond to a number of (similar or related) aspects, in which case it must be broken down into sub-elements for measurement.

Attribute Sort Value Description
tag required text Brief tag to identify the element in the hierarchy.
stake-holder optional text The source of this requirement (either an individual person, or an interested group).
date optional text The date that this requirement was added to the specification.
importance optional (critical | high | medium | low) The extent to which failure to meet this requirement would impact on the project as a whole. In particular, failure to meet a critical requirement would spell disaster for the project.

<resource> A resource constraint or a cost constraint in either constructing the system or in running it.

Contents: (summary, details?, scale?, test?, current?, worst?, plan?, best?, resource*)

Attribute Sort Value Description
tag required text Brief tag to identify the element in the hierarchy.
stake-holder optional text The source of this resource constraint (either an individual person, or an interested group).
date optional text The date that this requirement was added to the specification.
importance optional (critical | high | medium | low) The extent to which exceeding this resource constraint would impact on the project as a whole. In particular, exceeding a critical resource constraint would spell disaster for the project.

<scale> The scale or units of measurement for a quality or resource element.

Contents: Text (incl. bold, italic, and link)

<test> The procedure to be followed in order to measure a quality or resource.

Contents: Text (incl. bold, italic, and link)

<current> The level of a quality or resource observed within the current system.

Contents: (figure, justify?)

For most clients the system being specified replaces one currently in use, even if this is just a manual or paper-based system. The success of the new system will depend on it improving, in some way, over the performance or efficiency of the current system, or in cutting the costs.

<worst> The worst level of a quality or resource element which might still be judged acceptable.

Contents: (figure, justify?)

A quality or resource requirement is judged not to have been met if it is worse than this level.

<plan> The level of a quality or resource element that we plan to achieve. This is often considerably better than the worst level.

Contents: (figure, justify?)

<best> The highest level of a quality or resource element that we can possibly hope to achieve within the current project.

Contents: (figure, justify?)

<record> The highest level of a quality or resource element that has been achieved by anyone within the industry (state-of-the-art).

Contents: (figure, justify?)


© University of Leicester 2002. Please send any comments and bug reports to S.Ambler@mcs.le.ac.uk.