Mastering the Requirements Process

In our ongoing example, we have explored various aspects of the IceBreaker product in earlier chapters. Part of this product’s functionality is to record road temperatures and moisture levels each time this data is transmitted by the weather stations. Recording data is a functional requirement—it is part of the fundamental business process. Now suppose that this data has to be recorded within half a second; moreover, once it is recorded, no one except a supervising engineer is allowed to alter the data. These two requirements are non-functional, with the first being a performance requirement and the second a security requirement. Although these requirements are not part of the functional reason for the product’s existence, they are neede...