Security Assertion Markup Language (SAML) is a single sign-on protocol built on XML. It supports both authentication and authorization over SOAP/HTTP requests between an identity provider (IdP) and a service provider (SP).

Before communicating for identity verification, the two providers must define a SAML agreement and exchange initial information through metadata. This information includes details such as:

• Public keys used for encryption, supported encryption protocols, and endpoint URLs that specify where SAML messages should be sent.
• Supported binding methods and supported XML attribute formats.

Once both providers know these details about each other, they configure themselves accordingly.