Requirements for RDAP Servers providing Domain Name Data

When a request to publish an RDAP server is sent to the IANA, a basic set of tests are performed to ensure the supplied server is operational and minimally conformant in providing RDAP service. These tests are performed against top-level domain names for publication in the RDAP Bootstrap registry (as supplied via the Root Zone Management process), and for RDAP base URLs supplied by ICANN-accredited registrars for publication in the IANA Registrar ID registry.

Testing methodology

The interactive component of the test is performed with a HTTP HEAD request to a URL generated from the base URL for a randomly-generated domain. The response should:

  • Provide a 4xx HTTP response code if the domain does not exist in the RDAP service; or
  • Provide a 200 HTTP response code if the domain does exist in the RDAP service, plus a subsequent HTTP GET request and response that provides a JSON structure with a key of “objectClassName” and a value of “domain”.

Should the response return a 3xx HTTP response code, indicating a redirect, a subsequent request is sent to the target of the redirect. The expected response should fulfil the above criteria.

For top-level domains, if an RDAP server returns a rate limit response (429 HTTP Response Code), the automated test will fail as being inconclusive. Such requests can then be discussed with IANA staff for manual approval.


At this time, IANA does not list non-ASCII characters in RDAP base URLs. Non-ASCII components of host names should be provided as the corresponding A-labels, and non-ASCII components of paths should utilize URI-encoding.

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