Domain Whois Lookup

Whois lookup involves querying domain registries or registrars using the WHOIS protocol. The process typically includes connecting to a WHOIS server on port 43, sending a domain name query, and parsing the returned information. The implementation often requires handling various response formats from different registrars and dealing with rate limiting and access restrictions.

Reference: https://datatracker.ietf.org/doc/html/rfc3912