

You can easily check it by WHOIS:
$ whois dev.
% IANA WHOIS server
% for more information on IANA, visit http://www.iana.org/
% This query returned 1 object
domain: DEV
organisation: Charleston Road Registry Inc.
address: 1600 Amphitheatre Parkway
address: Mountain View CA 94043
address: United States of America (the)
# the rest of output omitted
And some hints gives Wikipedia: List of Internet top-level domains.
Resiliency dilemma. Which type of redundancy to choose.