Eg:
"target domain name. In fact, for the sake of redundancy, a domain name may have many

authoritative servers, spread around the world and also operated by different companies."

I can't see how that could work technically, but maybe I'm missing something - an example would be helpful

It could be a borderline case but I can think to a company which runs authoritative servers for its domain on its own and which buys a backup NS service from another company with servers out of borders.

Maybe I'm missing something too?

Thanks,

-- 
Pier Carlo Chiodi

The opinions expressed here represent my own and not those of any organization, entity or committee to which I may hold a position.