An SMTP open relay is a mail server that permits an unknown, outside sender to pass mail through the server to unknown, outside recipients, usually without the consent of its manager.
InterScan Messaging Security Appliance 7.0
The Trend Micro InterScan Messaging Security Appliance gives us a very comprehensive solution with built-in spam detection, anti-phishing, and IntelliTrap technology for detecting worms and viruses. We also get more aggressive spyware control by catching it in SMTP and POP3 streams. Since deploying the appliance, we’ve had no unwanted content on the network
InterScan Messaging Security System.