As we all know IdentityServer is built with the concept of the central identity provider and it is supporting single sign-on by default as part of its main feature, but the single sign out is not coming as a part of inbuilt feature till IdentityServer3. Now they have added support for front-channel and back-channel specification for server-side clients in IdentityServer4. Here, I am going to explain how single sign out works using back-channel configurations.

Web security is the first step towards creating any user applications now a days. It is not just enough to secure application with simple password authentication and use simple cookie/session for further user state management, rather than we need to use some strong authentication mechanism using different authentication protocols like OAuth 2.0, OpenId Connect, SAML2, WS-Federation etc.

Here I am going to demonstrate IdentityServer4, which is open source authentication provider built on the top of OpenId Connect and OAuth 2.0.