How to: Authentication and Authorization
* [AspNet.Security.OpenIdConnect.Server](https://github.com/aspnet-contrib/AspNet.Security.OpenIdConnect.Server) - OpenID Connect/OAuth2 server framework for OWIN/Katana and ASP.NET Core.
* [Auth0](https://github.com/auth0/auth0.net) - Hosted, enterprise-grade platform for modern identity.
* [Casbin.NET](https://github.com/casbin-net/Casbin.NET) - Authorization library that supports access control models like ACL, RBAC, ABAC in C#
* [Identity](https://github.com/aspnet/Identity) - ASP.NET Core Identity is the membership system for building ASP.NET Core web applications, including membership, login, and user data.
* [IdentityServer](https://github.com/IdentityServer/IdentityServer4) - IdentityServer for ASP.NET Core 1.0 & 2.0
  * [IdentityServer4.EntityFramework](https://github.com/IdentityServer/IdentityServer4.EntityFramework) - EntityFramework persistence layer
  * [IdentityServer4.MongoDB](https://github.com/diogodamiani/IdentityServer4.MongoDB) - MongoDB persistence layer
  * [IdentityServer4.EntityFrameworkCore](https://github.com/2020IP/TwentyTwenty.IdentityServer4.EntityFrameworkCore) - Entity Framework Core persistence layer
  * [IdentityServer4.Templates](https://github.com/IdentityServer/IdentityServer4.Templates) - dotnet cli templates for IdentityServer4.
* [Okta](https://github.com/okta/okta-aspnet) - Hosted, enterprise-grade platform for modern identity.
* [openiddict](https://github.com/openiddict/openiddict-core) - Easy-to-use OpenID Connect server for ASP.NET Core.
  * [oidc-debugger](https://github.com/nbarbettini/oidc-debugger) - OAuth 2.0 and OpenID Connect debugging tool.
* [stormpath-sdk](https://github.com/stormpath/stormpath-sdk-dotnet) - Build [simple, secure web applications](https://github.com/stormpath/stormpath-aspnetcore) with Stormpath and ASP.NET Core. 
* [stormpath-sdk](https://github.com/stormpath/stormpath-sdk-dotnet) - Build [simple, secure web applications](https://github.com/stormpath/stormpath-aspnetcore) with Stormpath and ASP.NET Core.(Deprecated: It will longer get updated as of March 2017 after joining OKTA) 
* [stuntman](https://github.com/ritterim/stuntman) - Library for impersonating users during development leveraging ASP.NET Identity.