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- IdP Discovery and Login UI Metadata Extension Profile
- Working draft from the Shibboleth Project, not yet submitted to OASIS (XML namespace likely to change). SAML metadata provides a mechanism for expressing some of the information necessary for SAML entities to successfully communicate with each other. However, in most SAML profiles there is also a user agent, usually representing an actual person, that also participates in the profiled message exchanges. This document defines a set of extensions to metadata that provide information necessary for user agents to present effective UIs and, in the case of IdP discovery, help recommend appropriate choices to the user.
- vCard XML schema
- This could be used to extend the Contact element of meta-data. The XMPP project is in the process of updating there specs to refer to this version produced by the CalDav group.
Putting this all together, the point is that a consuming TFP could obtain metadata as often as necessary from a number of "input" TFPs and in a single document, establish the means for ongoing trusted communication across all the relevant protocols with all of the qualifying IdPs, including, for example, filtering out IdPs that failed to meet necessary assurance standards.