CyberGlossary

Identity & Access

OpenID Connect (OIDC)

Also known as: OIDC

Definition

An identity layer built on top of OAuth 2.0 that lets clients verify a user's identity and obtain basic profile information via signed ID tokens.

OpenID Connect (OIDC) extends OAuth 2.0 with a standardized authentication protocol. In addition to OAuth access tokens, the authorization server issues an ID token — a signed JWT with claims describing the authenticated user (subject, issuer, audience, authentication time, attributes) — and exposes a UserInfo endpoint. Clients verify the token's signature, issuer, audience and expiry before trusting the identity. OIDC is the de-facto standard for web and mobile SSO, social login, and federation between identity providers. Compared to SAML it is more JSON/HTTP-friendly, easier to use on mobile and APIs, and supports modern features like PKCE, pairwise subject identifiers and DPoP for sender-constrained tokens.

Examples

  • A web app using "Sign in with Microsoft" via OIDC to authenticate corporate users.
  • A mobile app validating an ID token from Auth0 before granting access to user data.

Related terms