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As shown in the high-level view of the architecture, Community-specific services are connected to a single Community AAI, while Infrastructure Services can be connected to a single Infrastructure Proxy. Lastly, generic services are typically connected to more than one Community AAI. Each Community AAI in turn serves as a bridge between external identity providers and the proxies to the e-infrastructure services. Specifically, Community AAIs connect to eduGAIN as service providers but act as identity providers from the services point of view, thereby allowing users to use their credentials from their home organisations. Complementary to this, users without an account on a federated institutional Identity Provider are still able to use social media or other external authentication providers for accessing services.
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