I believe it depends.
If you asking about SSO (Single Sign On) which can be used for login purpose.
Check the below links and also search for Qlik Sense SSO in search.
You limit the user depending on the field which you like to restrict.
Role Based or Product Based.
The best way to achieve is the authorization is by using their NTNAME for login purpose while doing Section Access.
If you have an example script in place and you'd like to share?
We can look into the script and provide you the Section Access script depending on your desired field of restriction.
Section access does not prompt for a userid.
It automatically limits the data made available to the user that is logged in based on your code in the app.
So if User A logs into the hub and opens the app they see X. When User B logs into the hub and opens the app they see Y.
This is all based on whatever access you have setup in your Section access code.