Ignoring unqualified MX's ?

[Barry Margolin]

In article <20000323114125.A29743 at tfj.rnd.uni-c.dk>,
torben fjerdingstad  <unitfj-bind at tfj.rnd.uni-c.dk> wrote:
>You are right. localhost. is a fully qualified toplevel domain
>name.

Not in the normal root servers it isn't.

>Anyway, I believe email addresses like tfj at dk, tfj at net and
>other toplevel email adresses are illegal.

Since when?

>If that is correct, it is sane to discard MX and A records
>pointing to a toplevel domain. The well known toplevel
>domains neither have A or MX records.

I wouldn't be surprised if some TLD registrars might configure MX records
on their TLDs that go to their NIC address, e.g. allow you to send to
hostmaster at dk as a synonym for hostmaster at nic.dk.

We had a thread a month or two ago about the advisability of attaching A
and MX records to TLDs -- there are some potential problems if sites have
hostnames that match the TLD, since most resolvers will treat a name with
no dots as being unqualified in the local domain before trying it as a
fully-qualified name.  But that doesn't mean that they violate the
protocol.

-- 
Barry Margolin, barmar at bbnplanet.com
GTE Internetworking, Powered by BBN, Burlington, MA
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