A Login Is Only the Beginning. Who Can Do What?

ASP.NET MVC/Core

Business applications often serve several types of users. An administrator may manage records, a staff member may update assigned work, and a customer may only view their own information. These differences should be part of the application design from the beginning.

Separate identity from permissions

Authentication establishes who is signed in. Authorization decides which actions that person can perform. A successful login alone should never grant access to every screen or record.

Check permissions on the server

In ASP.NET MVC/Core, authorization checks belong on the server. Hiding a navigation item improves the interface, but the backend still needs to enforce the same rule. Protected controller actions and APIs must validate access before returning data or making changes.

Think about individual records

A role check may allow a user into a customer portal, but record ownership determines which customer data they can see. Check both the action permission and the requested record’s relationship to the current user.

Keep the design understandable

Start with a small set of roles that match actual responsibilities. Document what each role can do, then verify common allowed and denied scenarios as the application grows.