On Tue, Dec 28, 2004 at 07:26:53PM +0000, Leonard Mills wrote:
Hosts do not identify themselve as domains! Hosts can use domain as part
of the host's FQDN though.. So change wording in some fashion, I suggest:
Hate to be pedantic, but even back in 82[12] days the email RFCs
identified email addresses as (meaning, not the literal BNF):
<local-part>@<domain>
Thus, the HELO domain can be indistinguishable from a fully
qualified domain name. But it _is_ the domain for email purposes.
I think you're missing the point as well (although not so bad):
If the hostname is "somehost.someprovider.sometld" then:
a) somehost.someprovider.sometld is a domain
b) someprovider.sometld is a domain
c) sometld is a domain
and no, this is _not_ a multiple choice question.
"user(_at_)somehost(_dot_)someprovider(_dot_)sometld" -> <local-part>@<domain>
"user(_at_)someprovider(_dot_)sometld" -> <local-part>@<domain>
is valid in both cases. These domains differ but they both
qualify as domains. It is not just the domain for email
purposes; both are domains, period.
For HELO purposes, the domain to use is the FQDN of the
sending host so there's no choice but to use
"somehost.someprovider.sometld" (except for the address-literal
case of course).
This may seem nitpicking but since we're going to define
a standard, it is important to get it right. If we can't
even get DNS right, how are we going to get SPF right when
it builds on DNS ?!?
Alex