Security Assertion Markup Language 2.0 (SAML 2.0) is a version of the SAML OASIS standard for exchanging authentication and authorization data between security domains. SAML 2.0 is an XML-based protocol that uses security tokens containing assertions to pass information about a principal (usually an end user) between an identity provider and a web service. SAML 2.0 enables web-based authentication and authorization scenarios including single sign-on (SSO).