Hi Anindya,
Way before RIH (Reltio Integrations Hub), DTSS was the way to configure to access and bring in data from external data sources like NPI. Its called Data Tenant Subscriber Services. Using which, the data from NPI will be hosted within Reltio instance as a Data Tenant and there will be match rules between Customer Tenant (CT) and the Data Tenant (DT) using DTSS. We could go to the DT within Reltio and download a particular entity (HCP, HCO or Location) using a cloud icon present next to each record. It will then brought into CT and allows you to do whatever you plan to do with it or even push it to downstream applications like reporting, CRM etc. Attached screenshot can show you how it looks once configured using DTSS. With RIH, it will done differently though. Hope this helps.
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Bhaskar Nunna
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