IANA RDAP Bootstrap Discovery (RFC 9224)

Locate RDAP servers per TLD, IP, or ASN using IANA bootstrap files and local indexing strategies.

What is bootstrap

IANA publishes dns.json, ipv4.json, ipv6.json, asn.json mapping suffixes/resources to RDAP base URLs—no hard-coded server lists.

Lookup flow

  • 1. Cache bootstrap files (refresh daily).
  • 2. Longest suffix match for domains.
  • 3. Build REST URL: {base}/domain/{fqdn}.
  • 4. Handle referrals and HTTP errors.
curl -s https://data.iana.org/rdap/dns.json | jq '.services[0]'

Self-hosted tip

Whoga merges bootstrap + PSL + extra mappings into a local index for faster routing and offline fallback.