SpamAssassin

N-able Mail Assure cloud-based email security solution provides advanced threat protection for inbound and outbound email using collective threat intelligence, 24/7 email continuity, and long-term email archiving. The service includes a multitenant web-interface with predefined settings, reporting, and views designed to ensure control and visibility over email flows. N-able Mail Assure’s proprietary technology incorporates input from processing large volumes of email data that feeds the Intelligent Protection and Filtering Engine. This combined with real-time pattern threat recognition leveraging a variety of filtering technologies help protect against spam, viruses, phishing attacks, impersonation, spoofing, malware, and other email-borne threats.

Rspamd has been started to handle mail flows that has grown over the last decade by more than ten times. From the very beginning of the project, Rspamd was oriented on highly loaded mail systems with development focus on performance and scan speed. Rspamd is written in plain C language and it uses a number of techniques to run fast especially on the modern hardware. On the other hand, it is possible to run Rspamd even on an embedded device with a very constrained environment. You can also check the recent performance analyze article to have a better impression about how fast Rspamd could be. Rspamd can be treated as a faster replacement for SpamAssassin mail filter with the ability to scan ten times more messages using the same rules (by means of SpamAssassin plugin). In the next graph, you can see how switch to Rspamd from SA helped to reduce CPU load on scanner machines. Rspamd can work with the most popular mail transfer systems, such as Postfix, Exim, Sendmail or Haraka.