Is providing a user login a functional requirement of a system?

Question

Is providing a user login a non functional requirement?

Since this is concerned with security which is a non functional requirement, I feel that providing a user login is also non functional but again I feel that it is functional.

Answer 1

User logins are more of a "feature" than a "requirement."

If you said "System shall block user from access to [some area of the system] if they are not logged in," or "System shall block user from access to [some area of the system] if they don't have the necessary security credentials," then it would be a functional requirement.

Requirements should always be accompanied by a test that, when executed, constitutes proof to the stakeholders that a requirement has been met. Otherwise, it's not a requirement. "System shall have user logins" is not a requirement, because you can merely have user and password fields on some form and call it a login system.

Answer 2

A login is a function or specific behavior. You either have a login capability or you don't. As such, as requirement, it would be a functional requirement.

Performance, say, of login, is a non-functional requirement: a judgement of the quality of the implementation (rather than a feature is present/absent).

https://en.wikipedia.org/wiki/Non-functional_requirement

Answer 3

Security is a non-functional requirement as it is well known to everyone. Log-in is one way to achieve security .. so it is non-functional requirement.

Answer 4

Providing a User login is a feature. Functional requirement herein could be that the system must generate a temporary login and password for each user