Computer Science

Information Systems Analysis and Design

csc340

XIV. The Requirements Specification Document (RSD)

What is a RSD? What to include/not include in a RSD? include in a RSD? Attributes of a Well-Written RSD Well-Written RSD Organization of a RSD Sample Table of Contents Contents An Example

2002 John Mylopoulos

Software Requirements Specification 1

Information Systems Analysis and Design

csc340

The Requirements Specification Document (RSD)

This is the document that is generated by the requirements engineering process; the document describes all requirements for the system under design and is intended for several purposes: Communication among customers, users and designers -specification should be quite specific about what the system will look like externally Supporting system testing, verification and validation activities -- specification should include sufficient information so that when the system is delivered, it is possible to make sure that it meets requirements Controlling system evolution -- maintenance, extensions and enhancements to system should be consistent with requirements, else the requirements themselves must evolve

2002 John Mylopoulos

Software Requirements Specification 2

Information Systems Analysis and Design

csc340

Contents of a RSD

What to include in a RSD: A complete yet concise description of the entire external interface of the system with its environment, including other software, communication ports, hardware and user interfaces Functional requirements (also called behavioural requirements) requirements specify what the system does by relating inputs to outputs Non-Functional requirements (also called quality or nonbehavioural) define the attributes of the system as it operates behavioural What not to include in a RSD: Project requirements -- because these are development-specific and become irrelevant as soon as the project is over Designs -- because inclusion of designs is irrelevant to endusers and...