OpenID Connect

• Open ID Connect is a protocol on top of OAuth 2.0 framework.

• It provides authentication by introducing a new ID token which contains a new set of information and claims specifically for identity.

• With the ID token, OpenID Connect brings standards around sharing identity details among application.

• It introduces a new scopes and in the final exchanges the client retrieves both an Access Token and ID Token.

• To OAuth 2.0, below details are added

  • OIDC standardized scopes to openid, profile, email and address.

  • ID Token using JWT standard.

  • OIDC exposes standard /userinfo endpoint.

Why do we need it

• Initially openid connect was used only to perform delegated authorization.

• But eventually, clients started using them for authentication using social login.

• But as OAuth was only an authorization framework, it did not have a mechanism to share user details or user profile to identity to which user the access token belongs to.

• To solve this problem OpenID Connect was introduced.