Why shouldn I rely on Microsofts “Tarpit”?
For Exchange 2003 sites, recipient filtering and the “Tar Pit Technique” are Microsoft’s solutions to Reverse NDR and Directory Harvest attacks. CMS Technicians do not recommend following this tactic since it slows SMTP operations, stretching the connection time of the mail session. In the event of a DoS attack, the Tar Pit will quickly consume a mail server’s resources. Microsoft themselves are aware of the limitations of the Tar Pit Technique and issued this warning…
