[Mimedefang] Black Listed

[Peter A. Cole]

On Tue, 06 Apr 2004 13:15:09 +0000
Rob MacGregor <rob_macgregor at hotmail.com> wrote:

> 
> However, just because a host is listed to RECEIVE email doesn't mean it'll 
> be used to SEND email.  Heck, take a look at any of the ISPs I've used, or 
> even my domain host.  They have different hosts for incoming and outgoing 
> email.
> 
This is very true. I just meant that the receiving mail servers should be able to identify correctly formatted mail they receive, as well as being able to verify the identity of the mail server it is sent from (see below).

In fact, if I ever go down the path of receiving mail directly to my home mail server, it will have to be sent via my ISP's mail server due to them now closing port 25.
> 
> I don't remember ever seeing an RFC that says that only hosts defined with 
> MX records may send email.  Maybe you could point it out :)
> 
Errrr, my bad...

Was late at night, had a few beers... really should have said maybe we should update the RFC's to include this as a prerequisite.

I believe Exchange 2003 now checks reverse MX lookups. Not really relevant for MIMEDefang of course, but if you go to www.dnsreport.com and check a mail server out, you'll soon see why I say this should probably be important.

Of course, this is all my own opinion which may be totally useless in the great scheme of things  :-)

Pete