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Most of the native SP's core functionality is defined in shibboleth2.xml. Read that topic for a detailed breakdown. Key subcomponents are also listed below.
Metadata
Metadata defines a partner site's capabilities, endpoints, keys, and other useful information. The Shibboleth software implicitly trusts the metadata it is given and uses it as a basis for all of its runtime decisions and choices.
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Some mandatory configuration is always required to integrate the SP with a web server. Some servers also support a degree of "native" integration enabling the SP to be partly controlled from the web server's own configuration file(s).
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