Top 20 NuGet authentication Packages

Enable SAML v2.0 SSO for identity provider (IdP) and service provider (SP) ASP.NET Core applications. Includes SAML authentication middleware support. Example ASP.NET Core projects are available that demonstrate the simple to use SAML API and accompanying SAML configuration. Comprehensive document...
OpenID Connect server middleware for OWIN/Katana.
OAuth2 introspection middleware for ASP.NET Core.
A SAML2 Owin middleware, compatible with ASP.NET Identity for external logins.
ASP.NET Core middleware that enables an application to support basic authentication.
OpenID Connect server middleware for ASP.NET Core.
OpenID Connect extensions for the OpenID Connect server middleware.
OpenID Connect extensions for the OpenID Connect server middleware.
OAuth2 validation middleware for ASP.NET Core.
OpenID Connect primitives for the OpenID Connect server middleware.
OpenID Connect server components for OpenIddict.
Entity Framework Core stores for OpenIddict.
OpenIddict's core components, used to manage the applications, authorizations, scopes and tokens stored in the database.
Easy-to-use OpenID Connect server for ASP.NET Core.
OpenIddict token validation middleware for ASP.NET Core.
OpenIddict's abstractions.
OpenIddict binders for ASP.NET Core MVC.
ASP.NET Core authentication middleware for OpenID 2.0 providers.
.Net library for two-factor (or multi-factor) authentication using TOTP and QR-codes.
Relational entities for the Entity Framework Core stores.