Document Sharing Across Network Topologies - Whitepaper

[JohnMoehrke]

Proposed Work Item: FHIR Federation

Proposal Editor: Joe Lamy Work item Editor: Joe Lamy Date: 19 January 2021 Version: 1.0 Domain: ITI

The Problem

The concept of federation is relatively underspecified in FHIR at this time. The notion of “home community” is used by numerous IHE profiles to enable complex, large-scale heterogeneous networks. See [IHE ITI TF-1] E.9 “XCA Integration with XDS and non-XDS communities” for a number of examples of federated deployments enabled by XCA. FHIR does not have an explicit analog for home community. We would like to add this to the IHE FHIR-based profiles. This would support all-FHIR cases requiring federation (for example, crossing security boundaries) as well as bridging FHIR with non-FHIR mechanisms such as XCA. Our initial use cases address mCSD and MHD, but other profiles could be considered, as well as Appendix Z for common capabilities, such as a consistent encoding of HCID as a business identifier.

https://github.com/IHE/IT-Infrastructure/blob/master/Proposals/IHE_ITI_FHIR_Federation-Brief.docx

UPDATE: Overall scope and status as of 5/14/21

• Push to federated responder: in progress
  • Doc sharing (XCDR): out of scope because no change needed
  • Doc sharing (MHD, XDR): in scope, complete (intendedRecipient)
    • Still need to write a CP to XDR, but analysis done
  • Other FHIR resources: out of scope (X-Destination)
  • mCSD: enable federation and Endpoint lookup, profile id as HCID: in scope, in progress
• Pull from federated responder: in progress
  • Doc sharing (XCA): out of scope because no change needed
    • Could still describe big networks like Carequality in white paper
  • Doc sharing (MHD): in scope, in progress
    • Considering where in metadata the HCID of fed resp can be conveyed
  • mCSD: enable federation lookup, profile id as HCID: in scope, in progress
• Push or pull from federated initiator: just started
  • Routing response back to federated sender: out of scope because can be handled by initiating gateway
  • Which responding actor can perform access control / auditing: in scope, in progress
    • Briefly describe in white paper
    • No normative changes needed
  • Info needed to perform access control / auditing: in scope, in progress
    • Handle “multi-parent”, “multi-requester” use cases
    • IUA: representing initiator(s) in access request: in scope?
    • mCSD: representing different kinds of relationships: in scope
    • mCSD: enable federation lookup, profile id as HCID: in scope, in progress