Mail Server best practices - was: Pandora's Box of new TLDs

Roger Marquis marquis at
Sun Jun 29 14:55:07 UTC 2008

Rich Kulawiec wrote:
> notification is essential in order to provide a heads-up about
> problems (and that once problems are noticed, cooperation is
> essential in order to fix them). But mail should never be
> discarded without notice

In practice we've found that (notification) is the core issue.  Reject v
discard is a non-issue by comparison.

The format of those notifications does not have to be a spam folder, as
many seem to assume.  A summary report serves the purpose far better than
tagging and delivery with far less overhead.  Quoting
<> :

   The only reliable way to avoid false-positives is by monitoring
   the email server or gateway logs and allowing end-users to receive
   a daily report of email sent to their account that was identified
   as spam and filtered.

This is more or less identical to the issue ISP's like Comcast face when
implementing QOS or other filtering, when they fail to notify end-users.

Backscatter / NDNs are another issue.  In practice they are no longer
feasible without assurance that the sender is both valid and legitimate.
Bounces without these validations are usually spam and will get your server

Roger Marquis

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