The LAN Edge 7.6 Architect Study Guide identifies the following communication mechanisms between FortiGate and FortiSwitch:

C — FortiLink Protocol (Primary Management Protocol): The study guide states: " FortiLink, also known as the switch controller function, allows FortiGate firewalls to remotely manage FortiSwitch devices. FortiLink defines the management interface and remote management protocol between FortiGate and FortiSwitch, enabling seamless control and integration. " FortiLink is the foundational protocol for the entire management relationship.

B — HTTPS (REST API): The study guide confirms: " FortiGate applies the quarantine-related configuration for the quarantined device to FortiSwitch using the FortiSwitch REST API. " FortiGate communicates with FortiSwitch via HTTPS-based REST API calls for specific configuration pushes such as quarantine enforcement, port configuration, and security policy application.

A — SNMP: SNMP is referenced in the study guide as a management protocol used by FortiGate to monitor and gather status information from FortiSwitch devices. SNMP is a standard network management protocol used for monitoring switch status, which aligns with its role in FortiSwitch management.

Why the other options are wrong:

D is incorrect — CAPWAP (UDP 5246/5247) is the protocol used between FortiGate and FortiAP for wireless AP management, NOT between FortiGate and FortiSwitch. The study guide explicitly states: " FortiGate manages FortiAPs using the CAPWAP protocol. "

E is incorrect — IGMP is an IP multicast group management protocol. It plays no role in the management or control channel between FortiGate and FortiSwitch. It is not mentioned in the LAN Edge 7.6 study guide in the context of FortiSwitch management.