The Anti-Spam SMTP Proxy (ASSP) is an open-source, Perl based, platform-independent transparent SMTP proxy server.

Anti-Spam SMTP Proxy
Original author(s)John Hanna
Developer(s)Thomas Eckardt in association with the ASSP community
Stable release
2.8.1(23131) / May 11, 2023; 6 months ago (2023-05-11)
Preview release
2.8.2(23136) / May 16, 2023; 6 months ago (2023-05-16)
Written inPerl
Operating systemCross-platform
TypeEmail spam filter
LicenseGNU General Public License

Features edit

Some ASSP's features are:

  • Hidden Markov Model spam filtering
  • Bayesian spam filtering
  • whitelisting
  • Penalty Box (PB) trapping
  • DNSBL/RBL (Realtime Blackhole Listing)
  • URIBL (Uniform Resource Identifier Black Listing)
  • Multi-level SPF (Sender Policy Framework) validation and blocking
  • DKIM signing and validation
  • DMARC validation and reporting
  • SRS (Sender Rewriting Scheme) fix-up
  • Session Delaying/Greylisting and connection response delaying
  • Sender validation and recipient validation
  • Multi-level attachment blocking (based on block lists or allow lists or content based executable blocking)
  • As well as multiple RFC validation mechanisms.
  • Multi-threaded (Since version 2.x)
  • Platform independent (Written in Perl)

See also edit

External links edit