ingress SMTP

Frank Bulk frnkblk at
Sun Sep 14 00:02:48 CDT 2008

Apologies for not being more clear, because I see the responses going in
tangents I hadn't expected.

Most anti-spam products drop the connection or issue some kind of rejection
message during the SMTP exchange.  If the connection is dropped, the
subscriber's MTA/MUA will likely try and try again until it reaches
expiration time.  For MS Exchange I think that's two or three days.  For
Outlook Express, that message just sits in the Outbox.  If a rejection
message was issued, hopefully the sender can interpret what the MUA is
saying, or the MTA sends back an undeliverable.

So, for service providers who require their subscribers to smarthost
messages through their server, how are they letting the subscribers know in
some kind of active way?  


-----Original Message-----
From: Suresh Ramasubramanian [mailto:ops.lists at] 
Sent: Saturday, September 13, 2008 8:39 PM
To: Frank Bulk
Cc: Matthew Moyle-Croft; nanog at
Subject: Re: ingress SMTP

On Sat, Sep 13, 2008 at 11:38 PM, Frank Bulk <frnkblk at> wrote:
> How do you alert mail server operators who are smarthosting their e-mail
> through you that their outbound messages contain spam?
> Frank

If those are actual mailservers smarthosting and getting MX from you
then you doubtless have quite a lot of reporting already set up.

Have you seen what Messagelabs, MXLogic etc do?

There's also feedback loops, ARF formatted, where users on those
mailservers can report inbound spam to the filtering vendor.

.. or was that a rhetorical question and am I missing something here?

Suresh Ramasubramanian (ops.lists at

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