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InCommon metadata is updated at step 1 in advance of configuring the software for SAML V2.0. First add one or more SAML V2.0 endpoints to metadata, including at least one <md:AssertionConsumerService> endpoint and zero or more <idpdisc:DiscoveryResponse> endpoints. See the comprehensive wiki topic on SP Endpoints for requirements and recommendations.
Since a SAML V2.0 IdP typically encrypts assertions transmitted through the browser, the SP is obliged to add an encryption key to metadata as well. In the InCommon Federation, this will already be done since a key in SP metadata is designated as a multiple use key by default. (See the wiki topic on Key Usage for details.)
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