Barracuda firewall, where to start
It is designed to accommodate up to 100,000 users and process millions of email messages per day. You can also cluster together several Barracuda firewall units to increase capacity even further. Your Barracuda firewall uses 12 defensive layers, such as denial of service protection, sender authentication, recipient verification, virus scanning, intent and image analysis, Bayesian analysis, rule based scoring and rate control (which is triggered when your system receives a large number of messages from a single IP address over a short period of time), all of which are set through the web based interface by your administrator. The system can protect from either individual spam messages or brute force attacks. Barracuda firewall antivirus protection employs two separate filtering engines to catch potential system threats.