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Consider also that in some cases a service is already available via eduGAIN without you knowing it. This is sometime the case for publisher services that in pre-eduGAIN times were often registered with many national federations. When one of those national federations joined eduGAIN and exported their services, they become availabel available through eduGAIN as well. To verify if your service is already exported to eduGAIN look it up in the eduGAIN Entity Database:
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To register the Service Provider (SP) with a federation, one typically has to provide its SAML2 metadata to the federation operator. If you don’t have metadata about your SP yet, you might need to generate/compose it first. Shibboleth can generate SAML2 metadata about itself, just try accessing https://your.host.org/Shibboleth.sso/Metadata
SimpleSAML PHP SimpleSAMLphp has a similar feature. Just open the URL https://your.host.org/simplesaml/module.php/saml/sp/metadata.php/default-sp
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