WHO SMART Trust
1.1.2 - 1.1.2

WHO SMART Trust, published by WHO. This guide is not an authorized publication; it is the continuous build for version 1.1.2 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/WorldHealthOrganization/smart-trust and changes regularly. See the Directory of published versions

## Use Cases

### Federated PKD Aggregation

Keys from Local PKDs are aggregated in a federated PKD for use by verification applications.

ACTORS:

- Local PKD – acts as a node within a trust network​
- Aggregating/Federated PKD – trusted aggregation of public keys and trusted services from nodes

TRANSACTION: Mirror Local PKD

### Federated Verification

Verifications can cryptographically verify health credentials using keys retrieved from the Federated PKD.

ACTORS:

- Universal Verification Application – verifies health documents using Public Key Infrastructure (PKI)​
- Local PKD – acts as a node within a trust network​
- Aggregating/Federated PKD – trusted aggregation of public keys and trusted services from nodes

TRANSACTION: Request PKD

### Dynamic Business Rule Validation​

Validate one or more verified COVID credential against a dynamic business rule.​

ACTORS:

- Universal Verification Application – executes business rules against verified health documents​
- Business Rules Library – trusted service, provided by a node within a trust network, to share business rules using Clinical Quality Language (CQL) specification​

PRE-CONDITION: Verification Application has passed Verification Workflow​

TRANSACTIONS: Request Business Rule Updates, Execute Business Rule​

OUT OF SCOPE: consolidating business rules across trust network members​