SAML metadata
The SAML metadata standard belongs to the family of XML-based standards known as the Security Assertion Markup Language (SAML) published by OASIS in 2005. A SAML metadata document describes a SAML deployment such as a SAML identity provider or a SAML service provider. Deployments share metadata to establish a baseline of trust and interoperability. Introduction to SAML metadata To securely interoperate, partners share metadata in whatever form and by whatever means possible. In any case, at least the following metadata must be shared: Entity ID Cryptographic keys Protocol endpoints (bindings and locations) Every SAML system entity has an entity ID, a globally-unique identifier used in software configurations, relying-party databases, and client-side cookies. On the wire, every SAML protocol message contains the entity ID of the issuer. For authentication purposes, a SAML message may be digitally signed by the issuer. To verify the signature on the message, the message receiver uses a public key known to belong to the issuer. Similarly, to encrypt a message, a public encryption key belonging to the ultimate receiver must be known to the issuer. In both situations—signing and encryption—trusted public keys must be shared in advance. Once the message is signed and encrypted, the issuer