Auth in ASP.NET Core Architectures

Authentication and authorization are cross-cutting concerns in .NET Core systems.

Authentication: Who are you? (cookies, JWT, OpenID Connect).

Authorization: What are you allowed to do? (policies, roles, claims).

Use ASP.NET Core Identity or external identity providers (Azure AD, IdentityServer) for centralized auth.

Architecture impact: Centralized auth keeps security consistent across services and avoids duplicating logic.

Reference:

Microsoft: Authentication and Authorization

https://learn.microsoft.com/aspnet/core/security/authentication/