What authentication technology can be paired with OAuth to perform identity verification and obtain user profile information using a RESTful API?

OpenID Connect is a RESTful, JSON-based authentication protocol that, when paired with OAuth, can provide identity verification and basic profile information. SAML is the Security Assertion Markup Language, Shibboleth is a federated identity solution designed to allow web-based SSO, and Higgins is an open-source project designed to provide users with control over the release of their identity information.