Alligate

If a message survives the initial SMTP conversation, Alligate next applies a sophisticated set of user defined rules and scoring systems to further weed out unwanted email. Before a message is accepted and approved for relay to your mail server, you have numerous options for reliably identifying and rejecting the message if it meets the levels you have defined. Unlike most mail server integrated anti-spam solutions, Alligate allows you to simply refuse the message with a standard SMTP 550 error. Envelope Analysis - Alligate records every aspect of the envelope conversation and allows you to use the results of the envelope analysis as part of the overall testing process. Header Analysis - Alligate examines the header to ensure it is syntactically correct. Every element is checked, and you can define penalty points that are applied when Alligate finds something suspicious. Body Analysis - Alligate allows you to define complex rules using regular expressions to identify specific patterns. While this is not designed to do deep intensive scanning, it is still an effective tool, especially for prolific spam campaigns that use identifiable patterns. Whitelisting Options - Numerous options are available for whitelisting addresses, domains, as well as exclusions from other checks like Greylisting.. Counterweighting Options - Negative test points can be assigned based on header or message body contents to help eliminate false positives on spammy looking messages. Automatic Attack Detection - Alligate watches constantly for all kinds of attacks or abuses and will kick into action within seconds when one occurs. Automatic Backscatter Protection - Alligate tracks NDR activity to each user, and when a backscatter overload is detected, Alligate refuses further NDR messages until the problem abates. Click Here to Read the Full Online Documentation