Welcome to IdentityServer4
IdentityServer4 is an OpenID Connect and OAuth 2.0 framework for ASP.NET Core.
Authentication as a Service
Centralized login logic and workflow for all of your applications (web, native, mobile, services). IdentityServer is an officially certified implementation of OpenID Connect.
Single Sign-on / Sign-out
Single sign-on (and out) over multiple application types.
Access Control for APIs
Issue access tokens for APIs for various types of clients, e.g. server to server, web applications, SPAs and native/mobile apps.
Federation Gateway
Support for external identity providers like Azure Active Directory, Google, Facebook etc. This shields your applications from the details of how to connect to these external providers.