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SURFconext is a hub-and-spoke federation, which means all Identity Providers are only connected to a single Service Provider (namely: SURFconext) and all Service Providers are connected to a single Identity Provider (namely: SURFconext). However, an exception is made for Service Providers who offer their service through eduGAIN. Those entities must support mesh architecture. So if you are an Identity Provider from another federation and you would like to connect to a Service Provider from SURFconext, the hub is not involved. Instead, you connect to the Service Provider directly, which is normal in a mesh federation and most likely business as usual for you.
The following image describes how connecting entities within SURFconext and eduGAIN works (please click the image to see a larger version):
Common attributes in SURFconext
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