Antispam Configuration

Apache James Server Anti-Spam system can be configured via two main different mechanisms:

AntiSpam SMTP Hooks

"FastFail" SMTP Hooks acts to reject before spooling on the SMTP level. SpamAssasin hook can be used as a fastfail hook, therefore SpamAssassin must run as a server on the same machine as the Apache James Server.

SMTP Hooks for non-existent users, DSN filter, domains with invalid MX record, can also be configured.

AntiSpam Mailets

  • Black listing Mailet
  • Grey listing Mailet
  • SpamAssassin Mailet is designed to classify the messages as spam or not with an configurable score threshold. Usually a message will only be considered as spam if it matches multiple criteria; matching just a single test will not usually be enough to reach the threshold.
  • BayesianAnalysis in the Mailet uses Bayesian probability to classify mail as spam or not spam. It relies on the training data coming from the users’ judgment. Users need to manually judge as spam and send to, oppositely, if not spam they then send to BayesianAnalysisfeeder learns from this training dataset, and build predictive models based on Bayesian probability. There will be a certain table for maintaining the frequency of Corpus for keywords in the database. Every 10 mins a thread in the BayesianAnalysis will check and update the table. Also, the correct approach is to send the original spam or non-spam as an attachment to another message sent to the feeder in order to avoid bias from the current sender's email header.