I was reading about Shibboleth's metadata -- https://wiki.shibboleth.net/confluence/display/CONCEPT/Metadata#Metadata-Use(andnon-use)ofMetadata , and how it's used to identify IDPs and service providers involved in the SAML flow. If a service provider uses Shibboleth, what information does it need to see in its metadata before it will communicate with an IDP?
Further, if the IDP uses the same version of SAML (e.g. v2.0) but doesn't implement Shibboleth, does that mean that the entities can't communicate with each other?