The HSPC core mission necessitates a number of core services and content packages be made available to the membership, upon which higher-level assets and services may be developed in a collaborative manner. Terminology queries are one such service at the root of the dependency graph, and foremost on the organizational roadmap.

Requirements

These are not exhaustive, and do not capture fine-grained needs of terminology experts and clinical modelers.

Functional

• SHALL

...

• provide a FHIR-based API supporting code terminology resources.
• SHALL support $lookup and $subsumes operations.
• SHALL support SSO and SoF using OAuth 2 authorization and OIDC authentication.
• SHALL support unauthenticated read-only access.
• SHALL support authenticated read/write access.
• SHALL be scalable in a horizontal manner on demand.
• SHOULD support management using container-based images in ordinary VPS environments.

Non-Functional

• SHALL be F/OSS, per policy of any service promulgated as part of a reference architecture be available in an unencumbered manner.

Solution

Overview

Ontoserver https://ontoserver.csiro.au/ is a Ontoserver is a closed-source terminology service developed by the Austrailian eHealth Research Centre https://aehrc.com/Centre , supporting a FHIR-based CodeSystem API including the $lookup and $subsumes operations needed by a typical client application. HSPC operates a instance of Ontoserver in the Amazon cloud, and syndicates pre-indexed content from a CSIRO server in Australia to receive and install pre-built binary indexes. The base API is run in read-only mode at:https://ontoserver.hspconsortium.org/fhir

Architecture

Using CSIRO's demo in Australia has three main problematic areas:

• Round-trip packet latency to/from any client deployed in the US is high, and the public instance is not for production uses.
• SNOMED CT is localized, and US editions are not present in the AU system. Similarly, HSPC does not currently have use cases requiring AU-specific content.
• Licensing of content in the US is attained through individual NLM UMLS licenses, a matter that is not fully resolved but is easier to constrain by assuring services are bound to US jurisdiction.

Deficiencies

Ontoserver has several notable issues that must be resolved if it is to be the long-term production base of HSPC terminology services.

Licensing

The most immediate issue 

For these reasons, HSPC's

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