generated: '2026-07-19'
method: searched
source: https://lkcloud-api.readme.io/docs/authentication-2
docs: https://lkcloud-api.readme.io/docs/authentication-2
summary:
  types: [oauth2]
  primary: oauth2
  oauth2_flows: [clientCredentials]
  token_transport: Authorization Bearer header
  scopes_supported: false
  additional_headers:
  - SiteServiceKey
authorization_server:
  issuer: https://auth2.lkidentity.com
  token_endpoint: https://auth2.lkidentity.com/connect/token
  authorization_endpoint: https://auth2.lkidentity.com/connect/authorize
  introspection_endpoint: https://auth2.lkidentity.com/connect/introspect
  revocation_endpoint: https://auth2.lkidentity.com/connect/revocation
  openid_configuration: https://auth2.lkidentity.com/.well-known/openid-configuration
  token_endpoint_auth_methods_supported: [client_secret_basic, client_secret_post]
  id_token_signing_alg_values_supported: [RS256]
schemes:
- name: OAuth2ClientCredentials
  type: oauth2
  flow: clientCredentials
  token_url: https://auth2.lkidentity.com/connect/token
  grant_type: client_credentials
  credentials_issued_by: ELLKAY technical project team (client_id + client_secret per organization)
  token_type: Bearer
  expires_in_seconds: 7199
  applies_to: [LKCloud Interop API, LKCloud FHIR R4 API]
  note: >-
    OAuth2 scopes are NOT supported; any scope headers sent by a client are ignored.
    Endpoint authorization is granted per client_id / subscriber_id via ELLKAY-side API permissions.
- name: SiteServiceKey
  type: apiKey
  in: header
  parameter_name: SiteServiceKey
  role: routing
  secret: false
  note: >-
    Non-secret routing key issued by ELLKAY that directs the request to the correct
    connection/data source. Required alongside the OAuth2 Bearer token on Interop and FHIR calls.
- name: SubscriberKey
  type: apiKey
  deprecated: true
  status: legacy
  applies_to: [LKCloud Interop API]
  note: >-
    Subscriber-key authentication retained for backwards-compatibility only; NOT supported for FHIR.
    ELLKAY strongly encourages migrating to OAuth2. Slated for eventual discontinuation (no date set).