This object carries the name of the internal component or subsystem that generated the logged event, as a variable binding in the firewall's SNMP notification. Administrators use it to narrow down which part of the firewall's software, such as the packet filtering engine or VPN module, produced a given log entry. For example, seeing a source value referencing the VPN subsystem would direct an admin's troubleshooting toward VPN tunnel configuration rather than general firewall rules.