[dns-operations] check if a domain has been registered via DNS

[Robert Edmonds]

Viktor Dukhovni wrote:
> I was/am aware of the "com.de" delegation from "de."
> 
> I choose to not make much of a distinction between "uk." and "co.uk.",
> or "de." and "com.de.".  These are much the same sort of beast, 1LD
> and 2LD public suffixes.  If we we want to be strict about limiting
> the discussion to 1LDs, then my only examples are nic.co, domain.co,
> jobs.lk, and topjob.lk.

I think there's a pretty big difference between a ccTLD that provides
registrations out of a second-level domain, and someone who sells
third-level delegations out of a domain they've registered with a ccTLD.

I agree that com.de needs to be on the Public Suffix List for browser
reasons, though.

-- 
Robert Edmonds