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Let's now put together all that we have discussed

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and see how a requirements engineering process actually works.

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So, first of all, we saw that requirements engineering

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consists of three main steps. Elicitation of the requirements,

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in which we extract requirements from various sources. Modeling

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in which we represent the requirements using one or

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more notations or formal reasons and analysis, in which

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we identify possible issues with our requirements and there is

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actually a 4th step that we kind of mention

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but not explicitly. And this is the negotiation that can

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happen between the stakeholders and the developers, during which

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requirements are discussed and modified until an agreement is reached.

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So if you want to think of this as a

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process, so as a sequence of steps, we can see

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that we start from elicitation. So we start by eliciting

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an initial setup requirements. We negotiate and refine this set,

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then we model the resulting requirements. And finally, we

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analyze such requirements. However, the process doesn't really stop here.

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Why? Well, because as a result of the analysis,

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we might have to perform further elicitation. And so this

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process is not really a sequential one, but rather

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an iterative process. So, in practice, we continue to iterate

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over these four steps gathering a better and better understanding

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of the requirements at every iteration until we are happy

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with the settle requirement that we gather and stop the process.