The device, which comes in seven models, provides integrated antispam, antivirus, anti-phishing, and antispyware protection. It uses several techniques to protect an email server, including IP reputation analysis, sender authentication, user-specified policies, Bayesian analysis, and rule-based scoring. End -user control features allow for fine tuning and enhanced accuracy.

A single Barracuda Spam Firewall handles up to 30,000 active mail users; multiple units can be clustered for high availability. All models include outbound filtering techniques such as attachment scanning, virus filtering and rate control to ensure outgoing email is legitimate.

A system administrator monitors and manages the applications via a Web interface, and Barracuda's security operations center continuously updates the firewall with spam and virus definitions.