## Intersection of http://smart.who.int/trust/CodeSystem/KeyUsage-DEV and http://smart.who.int/trust/CodeSystem/KeyUsage-DEV

This is the CodeSystem that contains codes in both WHO GDHCN Key Usage CodeSystem - DEV (http://smart.who.int/trust/CodeSystem/KeyUsage-DEV) and WHO GDHCN Key Usage CodeSystem - DEV (http://smart.who.int/trust/CodeSystem/KeyUsage-DEV).

### Structure

Generated Narrative: CodeSystem c4dd589e-f0ca-446f-84c9-fa0d4300791a-18

This code system `http://hl7.org/fhir/comparison/CodeSystem/c4dd589e-f0ca-446f-84c9-fa0d4300791a-18` defines codes, but no codes are represented here

Code | Display | Definition
SCA | Signer Certificate Authority (SCA) | A certificate which acts a trust anchor in the verification of the certificate chain for the DSCs issued by a Trust Network participant
DSC | Document Signing Certificate (DSC) | A certificate which may be used to verify a digital signature within a Verfifiable Digital Health Certificate
DECA | Data Exchange Certificate Authority (DECA) | A certificate which acts a trust anchor in the verification of the certificate chain for the DESCs issued by a Trust Network Participant
DESC | Data Exchange Signing Certificate (DESC) | A certificate which may be used to initiate a secure data exchange connection (e.g. mTLS) between Trust Network Participants
TLS | Transport Layer Security (TLS) | Used for establishing (m)TLS connections with systems, in particular between the Trust Network Gateway and backend systems of a Trust Network Participant
UP | Upload (UP) | Used to verify digital signature of cryptographically signed content uploaded to services within the Global Digital Health Certification Network, in particular the Trust Network Gateway