According to the OT Security 7.6 Architect study guide section on Asset Management , specifically regarding FortiNAC Visibility :

Layer 2 Polling Data : Because each physical address is unique, FortiNAC identifies hosts as they connect to the network. The information gathered during this process fills in the physical address and location information in the database.

Visibility Components : The guide states that the physical address learned , the time it was learned , and where it was learned from provide the foundation of endpoint visibility in the form of " what, where, and when " information. This confirms that Where it was learned (Option A) and The time it was learned (Option D) are correct.

Exclusions :

Layer 3 Polling : The MAC-to-IP correlation (Option B) is explicitly defined as a function of Layer 3 polling , where the correlated IP address is added to the database record for the corresponding MAC address.

DHCP Fingerprinting : The host name or system name (Option C) and the operating system are gathered via DHCP fingerprinting , not layer 2 polling.