OpenID - OpenID is a safe, faster and easier way to log in to web sites.
IdentityServer - An open-source, standards-compliant, and flexible OpenID Connect and OAuth 2.x framework for ASP.NET Core
OAuth - OAuth is an open standard for authorization. It allows users to share their private resources (e.g.
DotNetOpenAuth - DotNetOpenAuth is a free-to-use compiled library that comes with the real support to your site visitor to login with the help of openIDs via getting control of the ASP.NET control onto the page.
Portier - An email-based, passwordless authentication service that you can host yourself.
Okta Workforce Identity - Okta Workforce Identity is utility software for enterprises that provides a new way of work that enable your employees, contractors, and partners to use technology on any device.