On 20 Jun 2011, at 02:24, Paul Vixie <vi...@isc.org> wrote:
>
> furthermore, the internet has more in it than just the web, and i know that
> "foo@sony." will not have its RHS ("sony.") treated as a hierarchical name.
Trailing dots are not permitted on mail domains.
There has been an ongoing argument about the interaction between unqualified
domains and TLDs in mail domains. RFC 2821 said single-label mail domains were
syntax errors, but this was probably an editorial mistake and RFC 5321 permits
them. It's probably safest to assume that a single-label mail domain is a local
unqualified domain which will have its qualifying labels appended by the
message submission server, and in other contexts all bets are off.
Tony.
--
f.anthony.n.finch <d...@dotat.at> http://dotat.at/
