Anti-spam methods
=================

Anti-spam software is mostly off-topic for Dovecot, since it is usually done on
MTA side. Dovecot does have an <antispam plugin> [Plugins.Antispam.txt] to
allow users to train antispam filter by moving mails to spam/ham mailbox, but
that's all. Still, this question gets asked once in a while, so here's a page
where you're free to give your own opinion about different methods and
software.*The opinions expressed in this page are not the official opinions of
Dovecot authors.*

FIXME: Please update this page. You had a lot to talk about in the mailing list
already [http://dovecot.org/list/dovecot/2012-July/067292.html], so I'd think
there will be no problem filling in this page. Here's a suggested format:

General Info
============

 * Article on Anti-spam techniques
   [http://en.wikipedia.org/wiki/Anti-spam_techniques] on Wikipedia

SMTP traffic analyzer
=====================

Postfix postscreen
------------------

 * postscreen [http://www.postfix.org/POSTSCREEN_README.html] Documentation

Postfix Access Policy Delegation
--------------------------------

 * policyd-weight [http://www.policyd-weight.org/] scores mails based on DNSBLs
   (RBL/RHSBL), HELO, MAIL FROM and client IP addresses before any queuing is
   done.

Greylisting
-----------

 * milter-greylist [http://hcpnet.free.fr/milter-greylist] can do greylisting
   and much more for Sendmail and Postfix. Blacklists, whitelists, and
   autowhitelists are supported to help reducing the impact of message delays.
   milter-greylist also features a flexible ACL system that lets you configure
   complex behaviors : greylist/whitelist/blacklist decision can be made on
   behalf of sender IP, sender and recipient e-mail addresses, time of day,
   sender IP presence in a DNSRBL... You can even look up a web service or a
   LDAP directory to decide what to do, which allows user-modifiable
   per-recipient configurations. Written in C, no external database required,
   can sync among multiple MX.
 * policyd [http://www.policyd.org] can be integrated with postfix, can do
   greylisting, auto-whitelisting, HELO checks, RBL checks. Uses a MySQL
   Database to share its information, so that any of your mail servers know
   about the greylisting tuples and blacklists/whitelists.
 * SQLgrey [http://sqlgrey.sourceforge.net/] is a Postfix policyd for
   greylisting; stores data in a SQL-DB. Can be configured/monitored with a
   WebUI (e.g.sgwi [http://www.vanheusden.com/sgwi/]).

Content scanning software
=========================

Spamassassin
------------

 * Spam filtering scores can be automatically updated using sa-update
   [http://wiki.apache.org/spamassassin/RuleUpdates/]

Amavis
------

 * Mail/Virus scanner. Can use multiple 'engines' for Virus and Spam scanning,
   sign and verify DKIM.amavisd-new [http://www.ijs.si/software/amavisd/]

dspam
-----

 * Wikipedia Article on DSPAM [http://en.wikipedia.org/wiki/DSPAM]

Commercial tools
================

 * Cloudmark

(This file was created from the wiki on 2014-02-11 22:29)
