Assp

Anti-Spam SMTP Proxy

Anti-Spam SMTP Proxy is a spam filter that sits on port 25 in front of your regular SMTP server sendmail, postfix, qmail, etc.

ASSP performs a number of configurable spam checks, and on detecting a spam message, provides an immediate 5xx SMTP error code back to the client. Non-spam messages are passed to your regular SMTP server for further processing and delivery. ASSP includes SSL and IPv6 support. It is a single script with a web-based configuration tool.

ASSP offers - a whitelist of known good senders - Bayesian checks on message headers and contents - recipient address validation using LDAP and RFC822 conformance - relay denial - HELO checking - SPF Sender Policy Framework checking - DNSBL DNS Block List checking using many DNSBL services - various SMTP error modes detection - Virus detection and many other spam detection techniques.

WWW http//assp.sourceforge.net/ WWW http//opal.com/jr/freebsd/ports/mail/assp/