FortiNAC-F serves as a central manager for security events originating from a diverse ecosystem of third-party security appliances, such as FortiGate, Check Point, and Cisco. Each vendor utilizes its own internal scale forseverity levelswithin syslog messages (e.g., Check Point uses a 1–5 scale, while others may use 0–7). To provide a consistent response regardless of the source, FortiNAC-F usesSeverity Mappingsto normalize these incoming values.

According to theFortiNAC-F Administration Guide, severity mappings allow the administrator to translate vendor-specific threat levels into standardizedFortiNAC Security Levels(such as High, Medium, or Low Violation). When a syslog message arrives, the parser extracts the vendor's severity code, and the system immediately references theSecurity Event Severity Level Mappingstable to determine how that event should be categorized internally. This normalization is vital because it allows a singleSecurity Alarmto be configured to respond to any "High Violation" event, whether it was reported as a "Critical" by one vendor or a "Level 5" by another. Without these mappings, the administrator would have to create separate, redundant security rules for every vendor to account for their different naming conventions and numerical scales.

"Each vendor defines its own severity levels for syslog messages. The following table shows the equivalent FortiNAC security level... To normalize these events, configure theSeverity Level Mappingsfound in the device integration guides. This allows FortiNAC to generate a consistent security event that can then trigger an alarm regardless of the reporting vendor's specific terminology." —FortiNAC-F Administration Guide: Vendor Severity Levels and Syslog Management.