On Tue, 16 Sep 2003, Dean Anderson wrote:
> On Tue, 16 Sep 2003, Bruce Campbell wrote:
>
> > On Tue, 16 Sep 2003, Edward Lewis wrote:
> >
> > For these items of software to change from using a stateless method of
> > existence-verification with low overhead, to using a semi-stateless method
> > of existence-verification with high overhead, is something akin to the Y2K
> > bug in scope, albeit without all the hype.
>
> The correct way to check for "domain existance" for email is to lookup an
> MX record.
That would be the correct method as defined in RFC2821 would it? The one
which specifies:
5. Address Resolution and Mail Handling
If no MX records are found, but an A RR is found, the A RR
is treated as if it was associated with an implicit MX RR,
with a preference of 0, pointing to that host.
> > Operationally, having one's not-low-overhead whois server being hit by
> > automated queries solely for existence-verification is a terrible state of
> > affairs.
>
> One shouldn't be doing whois queries. One just wants to know if the domain
> of the sender can receive email, back.
Yes. If I receive an SMTP connection purporting to be from
'[EMAIL PROTECTED]', and I follow the established standards for
seeing whether I can send mail back, I end up with 64.94.110.11 . Ergo,
as far as that domain is concerned, it can receive mail back.
( This was covered at least 40 messages ago, do try to keep up ).
--==--
Bruce.
