Which of the following attestation models is based on XML for SOAP-based web services?

The choice of Security Assertion Markup Language (SAML) is correct because SAML is specifically designed for facilitating single sign-on (SSO) and identity verification between different web services using XML-based data formats. In SAML, assertions are written in XML, which allows different applications to securely exchange authentication and authorization data over the web. SAML works over the Simple Object Access Protocol (SOAP), which is a protocol that uses XML to encode messages for web services communication.

This model enables organizations to implement a federated identity management system, where a user's identity and attributes can be transferred between identity providers and service providers. By utilizing XML, SAML ensures that the assertions are structured and easy to parse, which enhances interoperability among various systems that support SAML.

Other options present their own unique capabilities but do not specifically align with the XML and SOAP framework used by SAML. OpenID, for instance, is centered around user authentication but is not XML-based nor inherently designed for SOAP. JSON Web Tokens (JWT) utilize JSON rather than XML, making them incompatible with the SAML specification. Shibboleth, while it does implement SAML for federated identity management, is a specific implementation rather than a distinct model and may not emphasize SOAP to the