• Blacklisting of websites & domains: Barracuda Central maintains an up to date list of the largest and most aggressive known spammers. This list is maintained by both Barracuda and other anti-spam groups. This list is automatically updated on each Barracuda Spam Firewall.
• Keyword scanning of emails: This can be configured on a per user basis. Our scanning methods include a scoring system such that emails are scored based on a number of criteria. If the score is above a threshold, then that email is flagged as spam. The Barracuda Spam Firewall comes with default criteria and thresholds but you may change these.
• Checksum technology: Barracuda Central monitors email traffic through the Internet and uses checksum technology to keep track of the number of times a particular message has appeared on the Internet. If a message has appeared over a certain number of times, it is categorized as known spam. Checksums of known spam messages are utilized by the Barracuda Spam Firewall to block spam messages.
• Message authenticity checking: Several algorithms are utilized to verify the authenticity of a message. Some of these are simple checks to verify that the “from address” is authentic. Some are more complex relating to SMTP protocol.
• Blacklists and Whitelists: Domains, IP’s, and email addresses can be blocked or whitelisted (allowed through). These lists may be maintained on a per user basis or on a corporate basis.
• Rate controls: Utilized to stop denial of service attacks as well as dictionary based spam attacks. These are integrated and automatic in the Barracuda Spam Firewall.
• File type attachment blocking: You can block certain types of files, such as vbl scripts, from entering your company.

>Suspect emails get quarantined

These are just some of the Key Points.