Charter blocking Port 25

Todd Vierling tv at duh.org
Thu Jun 10 15:39:20 UTC 2004


On Thu, 10 Jun 2004, Jeroen Massar wrote:

: > That's why port 587 was invented.  It's the MSA (mail *submission* agent)
: > port, intended only for initial injection of mail into the SMTP delivery
: > network.  Learn it, believe it, use it.  8-)
:
: Mail *SPAM* Agent? ;)

Port 587 should always be authenticated.  If it isn't, that's a
misconfiguration.

(Of course, those of us on SPAM-L have even seen bots successfully perform
SMTP AUTH, but that's certainly in the minority.  Port-25 blocking for
dynamic/residential ranges is still considered good form, as it does cut
down significantly on the level of unauthenticated wormspew.)

-- 
-- Todd Vierling <tv at duh.org> <tv at pobox.com>



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