RWhois
From Wikipedia, the free encyclopedia
RWhois is Referral Whois, a separate protocol and standard from Whois. RWhois should not be confused with the ability for a Whois server to refer responses to another server, though RWhois has that same ability. In a nutshell, RWhois extends the concepts of Whois in a hierarchical fashion, potentially creating a system comparable to that of DNS (in terms of layout, not functionality).
With Whois, look-ups of assigned IP address space is often limited to the larger CIDR blocks (i.e. /24, /22, /16 and such). Only the major RIRs and Domain Registrars run Whois servers. So, for example, finding out what specific customer of Sprint's owns a particular IP would normally require directly contacting Sprint and requesting the information.
But if Sprint ran a RWhois server, you could use a RWhois client to look-up the specific IP and find out exactly what customer of Sprint's had that particular IP address assigned to them. RWhois is intended to be run by even smaller Local Internet Registries, to provided more granular information about IP address assignment.
Ideally, RWhois would replace Whois, providing an organized hierarchy of referrals where you could connect to any RWhois server, request a look-up and be automatically re-directed to the correct server(s). However, while the technological functionality is in place, adoption of the RWhois standard has been weak.
