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Note that when the Portal logins in, it receives an access token (AT) to the Service (not for either linked data repository). This is labelled, , “AT-Service”. (The prerequisite account linking is not shown in this diagram.) When the Portal requires a resource which is held by Synapse, it sends a request to the Service, which recognizes the request as being relevant to Synapse, obtains a Synapse access token (“AT-SYN”), issues the request, and returns the result. In short the Service acts a proxy to the Synapse REST APIs. The Service could similarly interact with RDCA-DAP to retrieve resources held there, and perhaps issue data access requests.
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