What is requirement said functional and non-functional(quality)? [closed]
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While studying software engineering some time ago, a formal and informal explanation was asked in the classroom about what it would be a non-functional requirement along with a example to better explain the content.
When trying to explain with my words about the concept of non-functional requirements , the synthesis looked like this:
Option 1
Requirement does not work is that event that cannot be predicted by the system so that the system may not be able to solve it because it is an unpredictable event. system you can solve the problem through an event partially but never completely, because if you could solve it would be a functional requirement.
Option 2 (the most correct)
The RF (functional requirements) apply when users interact directly with the system through events, and when some interaction occurs indirectly but that affects the user in this case apply the concept of RNF (requirements do not functional)
Context of an example used
The example:
Imagine that your system should be able to register all possible flights among all national trips, in this way it should be able to inform the boarding and disembarking time, the flight number, if it will make connection or air bridge among other details... The system should be able to adjust flight schedules in the event of delays.
Based on this small context we can list some RF (functional requirement).
RF01 : register flights
RF02 : register passengers
RF03 : register rotas
RF04 : register Brazilian states (places of origin and destination)
Now departing for the dark side of the force, an example of RNF (non-functional requirement)
RNF01 : delay Prevention.
Examples of reason for a delay: bad conditions in the time, delaying the flight or even canceling it.
Doubt
Regarding this explanation of non-functional requirement and the regarding the example used, is it correct to state both are in fact correct?
At the time the activity was not corrected and I was in doubt, and today when studying again about the content, I came across the need for an answer.
1 answers
Regarding this non-functional requirement explanation and regarding to the example used, is it correct to state both are in fact correct?
No, actually non-functional requirement does not have to do with events that cannot be predicted, first let's see the definition of requirements:
Non-functional requirements , " are the requirements related to the use of the application in terms of performance, usability, reliability, security, availability, maintenance and technologies involved. These requirements concern how the functionalities will be delivered to the user of the software."That is, non-functional requirements are requirements where the user does not interact directly with him.
Functional requirement , " defines a function of a software system or its component. The functional requirement represents what the software does, in terms of tasks and services.'I.e. requirements functional are requirements in which the user interacts directly with him, as you said, flight registration, passenger registration...
In your example, I would change the RNF01 to be something like, "in case weather conditions are not favorable, all flight delay processing should be performed in less than 20 seconds"
In the above example, it does not have to do with the fact that the climatic condition is bad, but rather with the fact that, implicitly, no interaction with the user, all flights be rescheduled in a certain period of time.