Authentication means determining who a particular user is. Authorization means applying rules about what they can do. Blazor contains features for handling both aspects of this.
It worth remembering how the overall goals differ between server-side Blazor and client-side Blazor:
- Server-side Blazor applications run on the server. As such, correctly-implemented authorization checks are both how you determine which UI options to show (e.g., which menu entries are available to a certain user) and where you actually enforce access rules.
- Client-side Blazor applications run on the client. As such, authorization is only used as a way of determining what UI options to show (e.g., which menu entries). The actual enforcement of authorization rules must be implemented on whatever backend server your application operates on, since any client-side checks can be modified or bypassed.