SE2 - lesson 03

Elisabeta di Nitto

14 October 2015

Requirement Engineering

Late error correction is costly

According to an EU survey,
Problems in software development are divided into:

> 50% requirement specification
50% requirement management

What makes RE so complex?

Multiple concerns
- functional, quality, development
- hard and soft concerns
Multiple stakeholders with different backgrounds
- clients
- users
- domain experts
- developers

What do requirements engineers do?

Eliciting information
Modelling and analisys
Communicating requirements
Negotiating and agreeing requirements
Managing and evolving requirements

The world and the machine

The machine: the portion of system to be developed
The world: Portion of the real world affected by the machine

The purpose of the machine is always in the world

World phenomena