Requirements Modelling and Specification for Service Oriented Architecture

3.7. Summary

Many different approaches to requirements engineering have been taken. These include the following major styles.

• Classic requirements engineering, usually involving the production of large, complex, written functional specifications.

• Formal methods based on logic; though these really only deal with the specification of systems and not requirements per se.

• Use cases. When used in the usual style these too fail to address the whole problem of requirements; they too are tools for system specification.

• Various approaches based on human factors.

• The Soft Systems Method.

• Jackson Problem Frames.

• Mixed approaches.

• Just Do It (JFDI) - which is to say that some approach exists but is unarticulated, so that it is hard to repeat or share with other teams.

The approach that is most appropriate depends heavily on the cultures of development organization and the customer and upon the type of problem: real-time, safety critical, embedded, mass-market, etc.

Requirements elicitation is the process whereby a development agency discovers what is needed and why. Requirements analysis is the process of understanding and modelling the requirements that have been or are being elicited.

UML is a notation and not a method. It has its origins in several earlier notations and methods originated in database design, programming languages, formal methods and the object-oriented analysis and design methods of the 1990s. It is a widely accepted standard and provides a common language for developers. There ...