15. Addressing / Endpoint discovery

Addressing turns an organization/node identifier into a reachable PIX Manager + CDR URL. It is a separate concern from the record-locator (§14).

15.1 Normative

  • The Tier MUST be able to turn an organization/node identifier (from localization, §14, or from a directed FROM ENDPOINT, §8) into the concrete endpoints it needs: the community’s PIX Manager (for §5 resolution) and the CDR base URL (for fan-out and follow-up). Proposed binding: IHE mCSD (Mobile Care Services Discovery) for this addressing/directory function.

  • The registry (N21) is the local materialisation of this mapping: Organizations ↔ Endpoints ↔ system_id/creating_system_id ↔ CDR base URLs.

15.2 The connectionType reconciliation

An openEHR Query API endpoint is not a FHIR REST endpoint. A directory built on mCSD, or any FHIR Endpoint registry, offers connectionType codes such as hl7-fhir-rest and dicom-wado-rs, none of which denote an openEHR AQL endpoint. N19 therefore requires a defined openEHR code such as openehr-rest-query, or a bound system value; an informal string does not satisfy it. A federation registry reusing mCSD Endpoint resources MUST use (or register) an openEHR-specific connectionType for the AQL endpoints and MUST NOT rely on hl7-fhir-rest to denote an openEHR Query API. (The Dutch GF directory, whose example endpoints carry hl7-fhir-rest, is one instance of this - see Annex B §B.2.)

15.3 Regional realisation

An mCSD-based national provider directory with a master source and separate write/read directory roles is one way to satisfy §15.1. The Dutch Generic-Functions realisation (GF-Addressing) is documented in Annex B (§B.2).