Internet Infrastructure Series

Practical internet infrastructure concepts: DNS, RDAP, WHOIS, IP allocation, ASNs, and registries.

1 chapter · about 22 min end to end

1. 01RDAP Explained — The HTTPS + JSON Replacement for WHOISYou've probably run `whois example.com` and gotten back a wall of plaintext, or just 'REDACTED FOR PRIVACY'. There's a successor — RDAP, the Registration Data Access Protocol — that ICANN officially made the required gTLD lookup protocol in January 2025. This chapter explains what RDAP is, why it exists, the exact URL/JSON format you'll get back, how the IANA bootstrap routes your query to the right server, real `curl` examples for domains/IPs/ASNs, how `redacted` works under GDPR, the gotchas no one tells you, and four real things developers actually build on top of it (availability checks, abuse contacts, expiration monitoring, threat intel).Beginner · 22 min