Palo Alto Networks IoT Security provides comprehensive visibility by passively monitoring network traffic. The Next-Generation Firewall (NGFW) forwards traffic logs and Enhanced Application Logs (EALs) to the Cortex Data Lake. The cloud-based IoT Security service then applies machine learning to this data to automatically discover, identify, and classify all connected devices without requiring agents or manual configuration on the devices themselves. This passive, automated approach is the fundamental best practice for achieving complete and continuous visibility across the entire network.

B. Disable logging for IoT traffic to reduce storage usage and improve firewall performance.

Disabling logging would eliminate the data source IoT Security requires, thereby preventing any visibility, discovery, or threat detection.

C. Configure IoT devices to send syslogs directly to Cortex Data Lake for threat analysis.

This is not the primary data collection method. Many IoT devices lack syslog capabilities, making this approach incomplete and impractical for comprehensive discovery.

D. Manually add IoT devices to the security policy to ensure proper monitoring.

Manual entry is not scalable, is prone to human error, and cannot discover new or unknown devices, defeating the purpose of a comprehensive visibility solution.

1. Palo Alto Networks IoT Security Administrator's Guide: "How IoT Security Works." The guide states, "IoT Security is a cloud-based security service that discovers and identifies all unmanaged IoT devices on your network... It does this by ingesting and analyzing the network traffic that your Palo Alto Networks Next-Generation Firewalls (NGFWs) and Prisma Access send to Cortex Data Lake." This confirms the passive monitoring and automatic discovery process.

2. Palo Alto Networks IoT Security Administrator's Guide: "Get Started with IoT Security." In the "Before You Begin" section, a key prerequisite is to "Configure your firewalls to forward logs to Cortex Data Lake." This directly contradicts option B and highlights the reliance on firewall logs, not device-generated syslogs (refuting C).

3. Palo Alto Networks IoT Security At-A-Glance Datasheet: "The first step to securing IoT is to have complete visibility of all devices... Palo Alto Networks IoT security is the industry’s most comprehensive solution delivering ML-powered visibility, prevention, and enforcement in a single platform." This emphasizes that visibility is the foundational first step and is achieved through automated, ML-powered discovery, not manual processes (refuting D).