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Leveraging the IdP-initiated SSO feature of the Shibboleth IdP, an HTTP client will authenticate to the IdP via HTTP Basic Authentication and push a signed SAML2 Response to a SAML2 HTTP-POST endpoint at the SP. The client code will be a fork of the dead entity scripts, a set of bash scripts that probe endpoints in InCommon metadata. (Some sample code is provided so you can see where we're headed.)
At the end of this exercise, the HTTP client code will be released as open source.
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