This document dates back to February January 2013, when we were doing design for V3 of the Shibboleth Identity Provider. The Shibboleth MDA (Metadata Aggregator) was also being designed around the same time, and there seemed to be an opportunity to make use of the MDA within the IdP as part of its metadata processing system. In the end, we went in a different direction but the notes are preserved here.
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