The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform-independent SMTP Proxy server which implements auto-whitelists, self learning Bayesian, Greylisting, DNSBL, DNSWL, URIBL, SPF, SRS, Backscatter, Virus scanning, attachment blocking, Senderbase and multiple other filter methods. Click 'Browse all files' to download the professional version 2.4.3 build 15075.
V1 development has been stopped at the end of 2014 (1.10.1 build 14365). Possibly there will be done some bugfixing in future.
Please upgrade to V2, which is and will be actively maintained.
- Multiple Weighted DNSBLs
- Multiple Weighted URIBLs
- Weighted Regular Expression Filtering
- Penalty Box
- Attachment Blocking
- ClamAV and FileScan
- Blocking Reporting
- LDAP support
- Backscatter Detection
- V2 - recipient replacement / GUI user access rights management
- V2 - MIME charset conversion / DKIM check and signing
- V2 - DB support for all hashes / level based open plugin support
- V2 - transparent proxy support / BATV check and signing
- V2 - Plugins: archive, full attachment check and replacement, OCR
- V2 - damping (steal spammers time)
- V2 - AUTH to relay host / POP3 collector
- V2 - configuration value and file synchronization
- V2 - Block Reports design could be customized
- V2 - Razor2 and DCC support via Plugin
- V2 - SNMP support (monitoring, configuring, controll-API)
- V2 - user group import (file or LDAP or command based)
- V2 - automatic crash analyzer Hidden Markov Model
- V2 - IPv6 socket support
- V2 - word stemming (several languages) for Bayesian analyzer
- V2 - Perl module autoupdate via PPM or CPAN
- V2 - Hidden Markov Model spam detection engine
- V2 - full unicode support
- V2 - DMARC support
- V2 - privat Whitelist (legacy, domain based, user based)
- V2 - privat IP and Domain lists (legacy, domain based, user based)
- V2 - CPU affinity settings
- V2 - web file commander
- V2 - graphical statistic output (SVG)
- V2 - native SSL support for target hosts
- V2 - client SSL-certificate validation
ASSP is a great product with many useful options. Actually I can't think of anything missing when it comes to features. Speed and and resource usage are also great, never had any issues with the system. The only downside is the webinterface. It is hard to navigate and find the correct option even for a long time user. Also the menu doesn't work properly in firefox.
I've been using ASSP since version 1.06 as developed by John Hanna. This is simply the best free anti-spam solution there is. You can run it under Windows or Linux or anything else that supports Perl, at least you used to be able to I haven't updated in awhile since it just works. At present my number of days of operation stands at 3803.638 days. Do the math. Yah it rocks.
Special requirement to prevent use of email for secure data from our BI tool. Thirty minutes to download all components and install. One hour to configure the smtp relay to drop email from recipients not in a white list. Not bad for a complex tool such as ASSP. You have my vote!