Let's verify each protocol:
C). FortiGate uses the FortiLink protocol to establish communication with FortiSwitch.# FortiLink is themanagement and control protocol, encapsulated over:
* LLDPfor discovery
* CAPWAP (UDP/5246-5247)for control channel
* DHB (Device Handshake Bus)inside CAPWAP frames
Thus,FortiLink is required.
D). CAPWAP is used to establish the control channel between FortiSwitch and FortiGate.# Although CAPWAP is commonly associated with FortiAP, FortiSwitchalso uses CAPWAPinternally when managed by FortiGate.
This is documented in:
* FortiSwitch Administration Guide
* LAN Edge deployment guide
SoD is correct.
B). UHTTPS is used by FortiGate to securely manage and configure FortiSwitch devices.# FortiLink session actually uses:
* Encrypted CAPWAP (over DTLS)
* UHTTPS (port 4433)for secure configuration exchanges
This protocol is mandatory for:
* Switch configuration synchronization
* Firmware upgrade
* NAC data exchange
* VLAN provisioning
ThereforeUHTTPS is indeed one of the key protocols.
Why the incorrect options are wrong:
A). SNMP can be used by FortiGate to manage FortiSwitch.#
* FortiGate doesnotuse SNMP to manage FortiSwitch.
* SNMP is for monitoring by external systems, not for FortiLink control.
E). IGMP is required for management.#
* IGMP is a multicast protocol, irrelevant for FortiGate-FortiSwitch management.